Environmental Adult Education is recognized as a “hybrid outgrowth of the environmental movement and adult education, combining an ecological orientation with a learning paradigm to provide a vigorous educational approach to environmental concerns” (Sumner, 2003).
In laymen’s terms, environmental adult education refers to efforts in teaching environmental issues and how individuals and businesses can manage or change their lifestyles and ecosystems to live sustainably. The overarching goal of this field of study is to educate our global societies to live more sustainably.
From the classroom to the forests, fields, streams and prairies, environmental adult education takes place in both formal and nonformal learning environments and programs.
History
Environmental adult education is a relatively new and unique field of study and practice. It is a community-based method in which educators listen and respect the input of learners, and all participants are considered essential (Haugen, 2006).
During the last thirty years, environmental adult education has evolved. For more than a century, environmental and conservation organizations taught adults environmental education with very little structure.
The United States was one of the first countries to officially recognize environmental education. During a joint House-Senate session in 1968, Congress acknowledged the importance of environmental education, and in 1970 passed the Environmental Education Act, which established the Office of Environmental Education (American Geological Institute 2000).
Timeline of the Ideology of Environmental Adult Education (EAE):
* Mid-1970s: EAE recognized as distinct field of study
* Late 1980s: EAE focus on learner experience
* Late 1990s, Early 2000: Focus shifted to how to teach EAE
* 1997: United Nations Educational, Scientific, and Cultural Organization (UNESCO) hosted conference on adult education with EAE being one of the 33 workshops presented
Wednesday, February 25, 2009
Earlier Environmental Education Initiatives
According to the UNESCO Web site, in 1968 it organized the first intergovernmental conference aimed at reconciling the environment and development, now known as “sustainable development”. In the following years, UNESCO and the United Nations Environment Program (UNEP) initiated three major declarations that defined environmental education. Those included:
* 1972: Stockholm Declaration. This document included seven proclamations and 26 principles “to inspire and guide the peoples of the world in the preservation and enhancement of the human environment.”
* 1975: Belgrade Charter. The product of the International Workshop on Environmental Education, this charter built upon the Stockholm Declaration by adding goals, objectives and principles for environmental education programs.
* 1977: Tbilisi Declaration. This document updated and clarified the Stockholm Declaration and the Belgrade Charter by including new goals, objectives, characteristics, and guiding principles of environmental education.
* 1972: Stockholm Declaration. This document included seven proclamations and 26 principles “to inspire and guide the peoples of the world in the preservation and enhancement of the human environment.”
* 1975: Belgrade Charter. The product of the International Workshop on Environmental Education, this charter built upon the Stockholm Declaration by adding goals, objectives and principles for environmental education programs.
* 1977: Tbilisi Declaration. This document updated and clarified the Stockholm Declaration and the Belgrade Charter by including new goals, objectives, characteristics, and guiding principles of environmental education.
Methods of Adult Environmental Education Training
Educators in this field of study consider environmental problems with a holistic approach that combines social, political and environmental concerns into community dilemmas (Haugen 2006).
Participatory methods allow learners to make connections between social issues and environmental problems. This connection allows adult learners to understand the core causes of major environmental issues and the resulting social inequalities. This method also allows educators to stress the importance of instilling environmental awareness so that learners do not forget their relationship with the natural world.
To summarize the methods of adult environmental education training, environmental adult educators strive to instill learners with:
* a knowledge of environmental problems and their causes
* the skills to engage in social activism to combat those problems
* the attitude of respect and connection to the natural world
* a desire to change current practices to protect the Earth
Environmental adult education generally takes place in a nonformal education setting. This means that the organized learning can take place in many forms including vocational education, literacy education and on the job training (Haugen 2006).
The Need for Adult Environmental Education
Environmental problems are a reality in today’s culture that cannot be ignored. Growing environmental troubles that the world is facing today include:
* Global warming
* Pollution
* Habitat devastation
* Overpopulation
* Waste disposal
* Diminishing resources
As you can see, education is the key to reaching environmental sustainability. In this instance, sustainability is defined as “developing a way of human living that will ensure an enduring and sufficient level of support from the earth’s resources” (Parker & Towner, 1993).
Programs and Organizations that Encourage Adult Environmental Education
Programs and Organizations that Encourage Adult Environmental Education
* Conservation education and governmental agencies such as the Forestry Service and the Environmental Protection Agency (EPA) were established to educate adults in broad areas of the environment.
* The Nature Conservancy, originally the Ecological Society of America, was formed in 1915 with the missions of supporting ecologists and preserving natural ecosystems.
* The 4-H Organization was also established to reach adults by educating youth in areas of new agricultural technology and environmental awareness.
* The Peace Corps, established in 1961, has worked to incorporate adult environmental education and conservation practices into its international programming. Volunteers assist in:
* Environmental education
* Recycling
* Wildlife protection
* Park management
* Alleviating water-borne diseases
* Providing potable water
* Project WET (Water Education for Teachers) is a nonprofit water education program and publisher. This program “promotes awareness, appreciation, knowledge and stewardship of water resources through the dissemination of classroom-ready teaching aids and the establishment of internationally sponsored Project WET programs.” Committed to global water education that is implemented at the community level, the mission of Project WET is to reach children, parents, educators, and communities of the world with water education (Project WET).
* Project WILD is a conservation and environmental education program for educators of students in kindergarten through high school. Project WILD addresses the need for human beings to develop as responsible citizens of our planet. It is based on the fact that young adults and educators have an interest in learning about the natural world (Project WILD).
* Project Learning Tree is a multi-disciplinary environmental education program for educators and students. A program of the American Forest Foundation, PLT meets education standards. The curriculum provides tools needed to bring the environment into the classroom and students into the environment. Topics range from wildlife, water and forests, to community planning, waste management and energy (Project Learning Tree).
Monday, February 9, 2009
Sechura Desert
The Sechura desert, also known as the Peruvian Desert or the Peru-Chile Desert, is a large stretch of desert extending north from the Atacama Desert along the northwestern South American coast. Most of the desert is located on the western coast of Peru, with small parts in Chile near the Atacama Desert.
Location and Naming
The desert occupies a strip along the northern Pacific coast of Peru south of Piura region, extending from the coast 20-100 km inland to the secondary ridges of the Andes Mountains. At its northern end near the city of Piura, the Sechura desert transitions to the Tumbes-Piura tropical-dry forests egoregion (an area that also covers eastern Lambayeque) composed of equatorial dry forests. The total area of the Sechura desert is 188,735 km².
Within Peru the Sechura Desert name is confined to the most northwestern portion of the country (Piura and Lambayeque regions). Foreign sources, such as the World Wildlife Fund, define it as the whole stretch of coastal desert from the northwestern tip of Peru to parts of northern Chile, bordering the Atacama Desert. Because of this and the fact that the strip of desert between the Atacama and the northwestern coast of Peru would otherwise be nameless, the entire arid region of the coast of Peru shall be hereby referenced as the Sechura Desert.
History
The name sechura derives from a culture that developed called the SEC, around the year 400 B.C. In 1728 the old Sechura town was destroyed by a tsunami and moved to its current location. During El Niño years, flooding is not uncommon; in 1998 the runoff from the floods poured into the coastal Sechura Desert. Where there had been nothing but arid hardscrabble waste for 15 years, suddenly, amazingly, there lay the second largest lake in Peru: 90 miles (145 kilometers) long, 20 miles (30 kilometers) wide, and ten feet (three meters) deep, with occasional parched domes of sand and clay poking up eerily from the surface.
Geography and Climate
The Peruvian Desert has a very low temperature range due to the moderating effect of the nearby Pacific Ocean, but because of the upwelling of cold coastal waters and because of subtropical atmospheric subsidence, the desert is one of the most arid on Earth. This should not be surprising considering its proximity to the driest place in the world, the Atacama Desert.
Summer (December through March) is warm and sunny with temperatures that average over 24 °C. In summer it ranges from 25º to 38º. The Winter (June through September) is cool and cloudy with temperatures that vary from 16º C during the night and 24º C during the day.
The numerous short rivers that cross the Sechura have supported human settlements for millennia. A number of urban cultures have flourished here, including the Moche, the Moche thrived on fish, guinea pigs, squash and peanuts. The Sican Culture (c.800-1300) succeeded the Moche, and are known for their lost wax goldsmithing. The rivers still support intensive irrigated agriculture on their fertile bottomlands. Two of Peru's five largest cities, including Piura,and Chiclayo, lie within the region.
Location and Naming
The desert occupies a strip along the northern Pacific coast of Peru south of Piura region, extending from the coast 20-100 km inland to the secondary ridges of the Andes Mountains. At its northern end near the city of Piura, the Sechura desert transitions to the Tumbes-Piura tropical-dry forests egoregion (an area that also covers eastern Lambayeque) composed of equatorial dry forests. The total area of the Sechura desert is 188,735 km².
Within Peru the Sechura Desert name is confined to the most northwestern portion of the country (Piura and Lambayeque regions). Foreign sources, such as the World Wildlife Fund, define it as the whole stretch of coastal desert from the northwestern tip of Peru to parts of northern Chile, bordering the Atacama Desert. Because of this and the fact that the strip of desert between the Atacama and the northwestern coast of Peru would otherwise be nameless, the entire arid region of the coast of Peru shall be hereby referenced as the Sechura Desert.
History
The name sechura derives from a culture that developed called the SEC, around the year 400 B.C. In 1728 the old Sechura town was destroyed by a tsunami and moved to its current location. During El Niño years, flooding is not uncommon; in 1998 the runoff from the floods poured into the coastal Sechura Desert. Where there had been nothing but arid hardscrabble waste for 15 years, suddenly, amazingly, there lay the second largest lake in Peru: 90 miles (145 kilometers) long, 20 miles (30 kilometers) wide, and ten feet (three meters) deep, with occasional parched domes of sand and clay poking up eerily from the surface.
Geography and Climate
The Peruvian Desert has a very low temperature range due to the moderating effect of the nearby Pacific Ocean, but because of the upwelling of cold coastal waters and because of subtropical atmospheric subsidence, the desert is one of the most arid on Earth. This should not be surprising considering its proximity to the driest place in the world, the Atacama Desert.
Summer (December through March) is warm and sunny with temperatures that average over 24 °C. In summer it ranges from 25º to 38º. The Winter (June through September) is cool and cloudy with temperatures that vary from 16º C during the night and 24º C during the day.
The numerous short rivers that cross the Sechura have supported human settlements for millennia. A number of urban cultures have flourished here, including the Moche, the Moche thrived on fish, guinea pigs, squash and peanuts. The Sican Culture (c.800-1300) succeeded the Moche, and are known for their lost wax goldsmithing. The rivers still support intensive irrigated agriculture on their fertile bottomlands. Two of Peru's five largest cities, including Piura,and Chiclayo, lie within the region.
Simpson Desert
The Simpson Desert occupies approximately 176,500 square kilometres of central Australia. It is located within, and near the common boundaries of the Northern Territory, South Australia and Queensland states of Australia. It is bounded to the west by the Finke River and Mabel Range, to the north by Adam Range, to the east by the Georgina and Diamantina Rivers, with Lake Eyre to the south. Average annual rainfall is less than 200 mm.
The Simpson Desert is underlain by the Great Artesian Basin, water from which rises to the surface at numerous natural springs, including Dalhousie Springs, and at bores drilled along stock routes, or during gas and oil exploration. As a result of exploitation by such bores, the flow of water to springs has been steadily decreasing in recent years.
The Simpson Desert is an erg which contains the world's longest parallel sand dunes. These north-south oriented dunes are static, held in position by vegetation. They vary in height from 3 metres in the west to around 30 metres on the eastern side. The most famous dune, Nappanerica, or, more popularly, Big Red (named by Simpson Desert traveller Dennis Bartell), is 40 metres in height. There are reportedly 1100 dunes in the Simpson.
The explorer Charles Sturt, who visited the region from 1844-1846, was the first European to see the desert, but it was not until 1936 that Ted Colson became the first white man to cross it in its entirety. The name Simpson Desert was coined by Cecil Madigan, after Alfred Allen Simpson, an Australian philanthropist, geographer, and president of the Royal Geographical Society of South Australia.
No maintained roads cross the desert. However, there are tracks that were made during seismic surveys in the search for gas and oil during the 1960s and 1970s. These include the French Line, the Rig Road, and the QAA Line. Such tracks are still navigable by well-equipped four-wheel-drive vehicles which must carry extra fuel and water. Towns providing access to the edge of the Simpson Desert include Oodnadatta to the southwest, and Birdsville in the east. Last fuel on the western side is at the Mount Dare hotel and store. Before 1980, a section of the Commonwealth Railways Central Australian line passed along the western side of the Simpson Desert. Within the Simpson, the ruins at Dalhousie Springs, Dalhousie Springs, Purnie Bore wetlands, Approdinna Attora Knoll and Poeppel Corner (where Queensland, South Australia and Northern Territory meet) are popular landmarks.
Because of the excessive heat and inadequately experienced drivers attempting to access the desert in the past, it has been decided to close the Simpson Desert during the summer of 2008-2009 — to save unprepared "adventurers" from themselves
The Simpson Desert is underlain by the Great Artesian Basin, water from which rises to the surface at numerous natural springs, including Dalhousie Springs, and at bores drilled along stock routes, or during gas and oil exploration. As a result of exploitation by such bores, the flow of water to springs has been steadily decreasing in recent years.
The Simpson Desert is an erg which contains the world's longest parallel sand dunes. These north-south oriented dunes are static, held in position by vegetation. They vary in height from 3 metres in the west to around 30 metres on the eastern side. The most famous dune, Nappanerica, or, more popularly, Big Red (named by Simpson Desert traveller Dennis Bartell), is 40 metres in height. There are reportedly 1100 dunes in the Simpson.
The explorer Charles Sturt, who visited the region from 1844-1846, was the first European to see the desert, but it was not until 1936 that Ted Colson became the first white man to cross it in its entirety. The name Simpson Desert was coined by Cecil Madigan, after Alfred Allen Simpson, an Australian philanthropist, geographer, and president of the Royal Geographical Society of South Australia.
No maintained roads cross the desert. However, there are tracks that were made during seismic surveys in the search for gas and oil during the 1960s and 1970s. These include the French Line, the Rig Road, and the QAA Line. Such tracks are still navigable by well-equipped four-wheel-drive vehicles which must carry extra fuel and water. Towns providing access to the edge of the Simpson Desert include Oodnadatta to the southwest, and Birdsville in the east. Last fuel on the western side is at the Mount Dare hotel and store. Before 1980, a section of the Commonwealth Railways Central Australian line passed along the western side of the Simpson Desert. Within the Simpson, the ruins at Dalhousie Springs, Dalhousie Springs, Purnie Bore wetlands, Approdinna Attora Knoll and Poeppel Corner (where Queensland, South Australia and Northern Territory meet) are popular landmarks.
Because of the excessive heat and inadequately experienced drivers attempting to access the desert in the past, it has been decided to close the Simpson Desert during the summer of 2008-2009 — to save unprepared "adventurers" from themselves
Pine barrens ,canopy forest,Lycaeides melissa samuelis,Agalinis acuta,Hemileuca maia
Pine barrens, also known as pine plains, sand plains, pinelands, pine bush, and pitch pine-scrub oak barrens, occur throughout the northeastern U.S. from New Jersey to Maine (see Atlantic coastal pine barrens) as well as the Midwest and Canada. Pine barrens are plant communities that occur on dry, acidic, infertile soils dominated by grasses, forbs, low shrubs, and scattered trees; most extensive barrens occur in large areas of sandy glacial deposits, including outwash plains, lakebeds, and outwash terraces along rivers. The most common trees are the Jack Pine, Red Pine, Pitch Pine, Blackjack Oak, and Scrub Oak; a scattering of larger Oaks is not unusual. The understory is composed of grasses, sedges, and forbs, many of them common in dry prairies. Plants of the heath family, such as blueberries and bearberry, and shrubs such as prairie willow and hazelnut are common. These species have adaptations that permit them to survive or regenerate well after fire. Pine barrens support a number of rare species, including lepidoptera such as the Karner Blue butterfly (Lycaeides melissa samuelis) and the barrens buck moth (), and plants such as the Sand-plain Gerardia (Agalinis acuta).
Barrens are dependent on fire to prevent invasion by woody species. In the absence of fire barrens will proceed through successional stages from savanna to closed-canopy forest. European settlers found extensive areas of open game habitat throughout the East, commonly called "barrens". The American Indians used fire to maintain such areas as rangeland. Open barrens are now rare and imperiled globally, as suppression of wildfires has allowed woody vegetation to take over in most one-time barrens. In North America, barrens exist primarily in the American Midwest and along the east coast.
In 1968, John McPhee published a book, entitled The Pine Barrens, exploring the history, ecology and geography of the New Jersey Pine Barrens, infused with his own personal memoirs.
Barrens are dependent on fire to prevent invasion by woody species. In the absence of fire barrens will proceed through successional stages from savanna to closed-canopy forest. European settlers found extensive areas of open game habitat throughout the East, commonly called "barrens". The American Indians used fire to maintain such areas as rangeland. Open barrens are now rare and imperiled globally, as suppression of wildfires has allowed woody vegetation to take over in most one-time barrens. In North America, barrens exist primarily in the American Midwest and along the east coast.
In 1968, John McPhee published a book, entitled The Pine Barrens, exploring the history, ecology and geography of the New Jersey Pine Barrens, infused with his own personal memoirs.
Tuesday, February 3, 2009
Western Islands, Papua New Guinea
The Western Islands are a group of islands in the Bismarck Archipelago, part of Papua New Guinea, off the northeastern coast of New Guinea in the western Pacific Ocean.
Islands :
Aua Island
Hermit Islands
Kaniet Islands
Ninigo Islands
Wuvulu Island
Islands :
Aua Island
Hermit Islands
Kaniet Islands
Ninigo Islands
Wuvulu Island
Western European broadleaf forests
This palaearctic ecoregion covers a large area in Western Europe (France, Austria and Germany), with in particular Massif Central, Jura, Central German Uplands, Bavarian Plateau and Bohemian Massif. It is essentially lowland and altimontane beech and mixed beech forests. It also includes small part of sub-Mediterranean areas. The total area is around 490,000 km².
The area biome is best defined by temperate broadleaf and mixed forests.
This area has been inhabited for thousands of years. It hosts large cities (Lyon, Nancy, Munich), some forests, but most of the countryside is agricultural land, cultivated with cereals (corn, wheat, oats). This ecoregion hosts a good variety of animal species, birds in particular, but most large mammals are in decline.
The area biome is best defined by temperate broadleaf and mixed forests.
This area has been inhabited for thousands of years. It hosts large cities (Lyon, Nancy, Munich), some forests, but most of the countryside is agricultural land, cultivated with cereals (corn, wheat, oats). This ecoregion hosts a good variety of animal species, birds in particular, but most large mammals are in decline.
Vegetation of New England and the Maritime Provinces
This area is dominated by a forest ecoregion called the New England-Acadian forests which is a temperate broadleaf and mixed forest. This forest type is a transition between mixed northern hardwood forests on the coastal lowlands and the boreal forests of the northern Maritimes. This entire area is largely a mosaic of habitats within this transition spectrum. The forest composition is influenced locally by micro-climatic differences and ecological disturbances. Essentially, there are four important community types which show considerable diversity and blending across this physiographic province. These communities are: alpine communities, coniferous forests, northern hardwood forests, and wetlands. There are no clear boundaries between the coniferous forests and the hardwood forests in the New England-Acadian ecoregion. The prevalence in the canopy of red pine (Pinus resinosa) and red spruce (Picea rubens) distinguish the transition forests of New England from those in the Great Lakes region to the west.
Physiographic region
The vegetation of the New England and Maritime Appalachian Highlands is similar throughout the New England Uplands, the White Mountains, the Green Mountains, and the Taconic Mountains. The physiographic province of New England and the Maritime provinces includes at least parts of Rhode Island, Connecticut, Massachusetts, Vermont, New Hampshire and Maine. It continues north to include New Brunswick, Nova Scotia, and Prince Edward Island. This entire area is sometimes referred to as the Atlantic Northeast. The seaboard lowlands of this region, which extends to mid-coastal Maine, exhibits a more mild climate and has a somewhat distinct vegetation in which hardwoods play a more important role. Some of western Vermont is in the Adirondack province, but generally exhibits similar vegetation.
Alpine communities
Alpine communities are essentially regions of Arctic tundra, or treeless tundra-like communities. These are restricted to the tops of mountains that reach above the tree line, about 1300 m. These tall mountains serve as refugia for arctic plants left over from the from the retreat of the Laurentide glacier at the end of the last ice age (the Wisconsin glaciation). The truest alpine tundra communities are located on the harsh western and northwestern slopes of tall mountains. The western slopes are typically heath dominated communities composed of plant of the family Ericaceae, changing to grasses and sedges toward the harsher northwestern faces. Common dominant components of the heaths are: alpine bilberry (Vaccinium uliginosum) and mountain cranberry (Vaccinium vitis-idaea).
Coniferous forests
Coniferous forests are found in the White Mountain regions and the northern parts of New England Uplands, primarily the middle interior of Maine and northwards and especially in areas between 1300 m and 900 m elevation. It is also found on parts of the immediate coast in Maine and the Maritimes. The coniferous forest goes by many names, some of which include: boreal forest, spruce-fir forest, the North Woods, and the taiga. It is noted in New England for its "harsh" conditions such as cold, subarctic temperatures, a short growing period, sandy-gravely acidic soil, and a high rate of leeching of nutrients out of the soil. It is also noted for a high rate of precipitation, year round, as rain and snow, which contributes to much of the leeching.
The dominant canopy species of this are include: red pine (Pinus resinosa), balsam fir (Abies balsamea), paper birch (Betula papyrifera), red spruce (Picea rubens), which northwards, is replaced by white spruce (Picea glauca). Also present are jack pine (Pinus banksiana), and white pine (Pinus strobus) which is found in areas of richer soil in the lower elevations of this forest. The presence of paper birch (Betula papyrifera), a successional species, is often an indication of past disturbances such as fire or logging in the forest.
Typical woody understory and shrub layer species include moosewood (Acer pensylvanicum), low-bush blueberry (Vaccinium angustifolium) and other heath species especially the genera Gaylussacia and Vaccinium.
Woody plants of the ground cover layer include American wintergreen (Gaultheria procumbens) and partridge berry (Mitchella repens). Common wildflowers include: star flower (Trientalis borealis), bluebead Lilly (Clintonia borealis), foam flower (Tiarella cordifolia), bunchberry (Cornus canadensis), twinflower (Linnaea borealis), dewdrops (Dalibarda repens), wild sarsaparilla (Aralia nudicaulis), and Canada mayflower (Maianthemum canadense). Trilliums, and yellow lady slippers (genus Cypripedium) are also common showy wildflowers. The herbaceous layer also includes many mosses, lichens, and ferns. Bracken fern (Pteridium aquilinum) is often particularly abundant in these communities.
Northern hardwood forest
These forests also go by the names: hemlock-northern hardwoods, and mixed forests. The northern hardwoods are located in the seaboard lowlands and south of the coniferous forests, but there is considerable blending of the two communities. These forests are typical of elevations below 700 m. Elements of these communities mix extensively with coniferous forest elements between 700 m and 900 m, and also from mid-latitude Vermont and New Hampshire north to central Maine where coniferous forest elements begin to dominate. Typically the richer the soils, and the more temperate the climate, the more dominant hardwoods will be. This forest type is considered the northern extension of the mixed mesophytic deciduous forest.
The four dominant canopy species of the hemlock-northern hardwood forests are sugar maple (Acer saccharum), beech (Fagus grandifolia), yellow birch (Betula alleghaniensis) and hemlock (Tsuga canadensis). Other common canopy assocites are include: white ash (Fraxinus americana), red maple (Acer rubrum), and northern red oak (Quercus rubra), which becomes less and less common northwards, dropping out almost entirely by mid-Vermont and New Hampshire. White oak (Quercus alba) is also an important canopy species in southern New England's seaboard lowlands. White pine (Pinus strobus) and red pine (Pinus resinosa), are also an important part of this mixed forest. The pioneer trees of this forest are quaking aspen (Populus tremuloides) and paper birch (Betula papyrifera).
Wetlands
Wetlands are defined anywhere by an abundance of water, hydric soils, and a unique flora. The wetland of the New England area exhibit considerable diversity across the range and elevations within the three category: bogs, swamps, and bottomlands. Swamps and bogs are specific habitats whereas bottomlands are any moist area including riparian zones, lake and pond banks, and the moist area surrounding bogs, marshes and swamps.
Bogs
Bogs are wetland areas, characterized by acid hydric soils composed of peat. Bogs can occur at any elevation in this ecoregion. They are often sphagnum heath areas dominated by shrubs in the family Ericaceae including: Leather leaf (Chamaedaphne calyculata), bog rosemary (Andromeda polifolia), Labrador tea (Ledum groenlandicum), bog laurel (Kalmia polifolia), and American cranberry bushes (Vaccinium macrocarpon). Throughout New England these areas are often artificially made for cranberry monocultures by commercial farms. Common components of the herb layer in bogs includes the carnivorous plants: round-leaved sundew (Drosera rotundifolia), and pitcher plant (Sarracenia purpurea). Other herbs common herbs of the poor soils of bogs include: false mayflower (Maianthemum trifolium), and some Orchids, particularly, bog candles (Platanthera dilatata). The most common trees that invade bogs as they fill in are: black spruce (Picea mariana), northern white cedar (Thuja occidentalis), larch (Larix laricina) and black ash (Fraxinus nigra).
Swamps
Swamps are typically characterized by hydric soils and have more of a canopy than bogs. The most characteristic trees of southern southern and low altitude New England swamps are: hemlock (Tsuga canadensis), white cedar (Thuja occidentalis), tamarack (Larix laricina), balsam poplar (Populus balsamifera), and black ash (Fraxinus nigra). Often cool, moist shaded ravines are dominated by pure stands of hemlocks in this range. In northern and high altitude swamps of New England the dominant canopy species change to tamarack, black spruce (Picea mariana) and balsam fir (Abies balsamea). The understory across the range consists of a number of Viburnum species among others.
Bottomlands
The bottomlands and margin areas in the Northern Hardwood communities are primarily dominated by: red maple (Acer rubrum), balsam poplar (Populus balsamifera), black ash (Fraxinus nigra), eastern cottonwood (Populus deltoides), and the silver maple (Acer saccharinum). The bottomlands and margin areas of the coniferous forests consist of: red maple, silver maple, white cedar, and balsam poplar. In wet areas throughout the region many sub-canopy species of willow (Salix spp.) occur as does speckled alder (Alnus rugosa) which is very common.
Physiographic region
The vegetation of the New England and Maritime Appalachian Highlands is similar throughout the New England Uplands, the White Mountains, the Green Mountains, and the Taconic Mountains. The physiographic province of New England and the Maritime provinces includes at least parts of Rhode Island, Connecticut, Massachusetts, Vermont, New Hampshire and Maine. It continues north to include New Brunswick, Nova Scotia, and Prince Edward Island. This entire area is sometimes referred to as the Atlantic Northeast. The seaboard lowlands of this region, which extends to mid-coastal Maine, exhibits a more mild climate and has a somewhat distinct vegetation in which hardwoods play a more important role. Some of western Vermont is in the Adirondack province, but generally exhibits similar vegetation.
Alpine communities
Alpine communities are essentially regions of Arctic tundra, or treeless tundra-like communities. These are restricted to the tops of mountains that reach above the tree line, about 1300 m. These tall mountains serve as refugia for arctic plants left over from the from the retreat of the Laurentide glacier at the end of the last ice age (the Wisconsin glaciation). The truest alpine tundra communities are located on the harsh western and northwestern slopes of tall mountains. The western slopes are typically heath dominated communities composed of plant of the family Ericaceae, changing to grasses and sedges toward the harsher northwestern faces. Common dominant components of the heaths are: alpine bilberry (Vaccinium uliginosum) and mountain cranberry (Vaccinium vitis-idaea).
Coniferous forests
Coniferous forests are found in the White Mountain regions and the northern parts of New England Uplands, primarily the middle interior of Maine and northwards and especially in areas between 1300 m and 900 m elevation. It is also found on parts of the immediate coast in Maine and the Maritimes. The coniferous forest goes by many names, some of which include: boreal forest, spruce-fir forest, the North Woods, and the taiga. It is noted in New England for its "harsh" conditions such as cold, subarctic temperatures, a short growing period, sandy-gravely acidic soil, and a high rate of leeching of nutrients out of the soil. It is also noted for a high rate of precipitation, year round, as rain and snow, which contributes to much of the leeching.
The dominant canopy species of this are include: red pine (Pinus resinosa), balsam fir (Abies balsamea), paper birch (Betula papyrifera), red spruce (Picea rubens), which northwards, is replaced by white spruce (Picea glauca). Also present are jack pine (Pinus banksiana), and white pine (Pinus strobus) which is found in areas of richer soil in the lower elevations of this forest. The presence of paper birch (Betula papyrifera), a successional species, is often an indication of past disturbances such as fire or logging in the forest.
Typical woody understory and shrub layer species include moosewood (Acer pensylvanicum), low-bush blueberry (Vaccinium angustifolium) and other heath species especially the genera Gaylussacia and Vaccinium.
Woody plants of the ground cover layer include American wintergreen (Gaultheria procumbens) and partridge berry (Mitchella repens). Common wildflowers include: star flower (Trientalis borealis), bluebead Lilly (Clintonia borealis), foam flower (Tiarella cordifolia), bunchberry (Cornus canadensis), twinflower (Linnaea borealis), dewdrops (Dalibarda repens), wild sarsaparilla (Aralia nudicaulis), and Canada mayflower (Maianthemum canadense). Trilliums, and yellow lady slippers (genus Cypripedium) are also common showy wildflowers. The herbaceous layer also includes many mosses, lichens, and ferns. Bracken fern (Pteridium aquilinum) is often particularly abundant in these communities.
Northern hardwood forest
These forests also go by the names: hemlock-northern hardwoods, and mixed forests. The northern hardwoods are located in the seaboard lowlands and south of the coniferous forests, but there is considerable blending of the two communities. These forests are typical of elevations below 700 m. Elements of these communities mix extensively with coniferous forest elements between 700 m and 900 m, and also from mid-latitude Vermont and New Hampshire north to central Maine where coniferous forest elements begin to dominate. Typically the richer the soils, and the more temperate the climate, the more dominant hardwoods will be. This forest type is considered the northern extension of the mixed mesophytic deciduous forest.
The four dominant canopy species of the hemlock-northern hardwood forests are sugar maple (Acer saccharum), beech (Fagus grandifolia), yellow birch (Betula alleghaniensis) and hemlock (Tsuga canadensis). Other common canopy assocites are include: white ash (Fraxinus americana), red maple (Acer rubrum), and northern red oak (Quercus rubra), which becomes less and less common northwards, dropping out almost entirely by mid-Vermont and New Hampshire. White oak (Quercus alba) is also an important canopy species in southern New England's seaboard lowlands. White pine (Pinus strobus) and red pine (Pinus resinosa), are also an important part of this mixed forest. The pioneer trees of this forest are quaking aspen (Populus tremuloides) and paper birch (Betula papyrifera).
Wetlands
Wetlands are defined anywhere by an abundance of water, hydric soils, and a unique flora. The wetland of the New England area exhibit considerable diversity across the range and elevations within the three category: bogs, swamps, and bottomlands. Swamps and bogs are specific habitats whereas bottomlands are any moist area including riparian zones, lake and pond banks, and the moist area surrounding bogs, marshes and swamps.
Bogs
Bogs are wetland areas, characterized by acid hydric soils composed of peat. Bogs can occur at any elevation in this ecoregion. They are often sphagnum heath areas dominated by shrubs in the family Ericaceae including: Leather leaf (Chamaedaphne calyculata), bog rosemary (Andromeda polifolia), Labrador tea (Ledum groenlandicum), bog laurel (Kalmia polifolia), and American cranberry bushes (Vaccinium macrocarpon). Throughout New England these areas are often artificially made for cranberry monocultures by commercial farms. Common components of the herb layer in bogs includes the carnivorous plants: round-leaved sundew (Drosera rotundifolia), and pitcher plant (Sarracenia purpurea). Other herbs common herbs of the poor soils of bogs include: false mayflower (Maianthemum trifolium), and some Orchids, particularly, bog candles (Platanthera dilatata). The most common trees that invade bogs as they fill in are: black spruce (Picea mariana), northern white cedar (Thuja occidentalis), larch (Larix laricina) and black ash (Fraxinus nigra).
Swamps
Swamps are typically characterized by hydric soils and have more of a canopy than bogs. The most characteristic trees of southern southern and low altitude New England swamps are: hemlock (Tsuga canadensis), white cedar (Thuja occidentalis), tamarack (Larix laricina), balsam poplar (Populus balsamifera), and black ash (Fraxinus nigra). Often cool, moist shaded ravines are dominated by pure stands of hemlocks in this range. In northern and high altitude swamps of New England the dominant canopy species change to tamarack, black spruce (Picea mariana) and balsam fir (Abies balsamea). The understory across the range consists of a number of Viburnum species among others.
Bottomlands
The bottomlands and margin areas in the Northern Hardwood communities are primarily dominated by: red maple (Acer rubrum), balsam poplar (Populus balsamifera), black ash (Fraxinus nigra), eastern cottonwood (Populus deltoides), and the silver maple (Acer saccharinum). The bottomlands and margin areas of the coniferous forests consist of: red maple, silver maple, white cedar, and balsam poplar. In wet areas throughout the region many sub-canopy species of willow (Salix spp.) occur as does speckled alder (Alnus rugosa) which is very common.
Trekforce Expeditions
Trekforce is a gap year and career break organisation that sends participants to remote destinations. For nearly 20 years, Trekforce has balanced trekking with conservation projects, aiding local communities and exploring new surroundings. It remains a pioneering organisation in the industry and leads expeditions to a number of diverse regions around the world.
History
Wandy Swales was the inspiration and spirit behind Trekforce. He was one of the late and great original explorers. Like every explorer he inspired those he came into contact with. Wandy also co-led Operation Drake (the precursor to Operation Raleigh). Realising the great work that expeditions can do for the host country as well as the participant, Wandy founded Swale Treks and started leading true adventurous expeditions in the mid 1980s exclusively to Indonesia, where at the time many of the 30,000 islands were uninhabited.
Swale Treks turned into the charity: The International Scientific Support Trust in 1990. This in turn became Trekforce Expeditions to reflect the changing nature of project-based expeditions. The early 1990s saw an increase in the popularity of expeditions. Trekforce has always placed an important emphasis on leadership and their staff have included Bruce Parry, Doug Warner, Ed Swales, Damian Taylor, Corrin Adshead, Lizzy Ellis and Steve Oliver who were all involved in carrying on the great work from Wandy and his fellow supporters. Trekforce Expeditions was continued by Rob Murray John, who then set up Trekforce Worldwide to carry on the legacy of Trekforce Expeditions.
Trekforce Expeditions was a UK-registered Youth Development Charity (No. 1005452) running from 1990 to 2006, which ran two-month jungle expeditions in places such as Belize, Borneo and Guyana where it conducted various conservation projects. The volunteers were predominately from the UK, aged 17-25, with the aim being personal development whilst contributing to remote infrastructure projects in these countries. It is now a limited company and still promotes the original environmental and adventurous principles that it was founded on.
In February 2008, Trekforce was acquired by Greenforce, another gap year company that places a strong emphasis on conservation and the environment. Greenforce specialises in marine conservation and terrestrial projects. In April, they became well known for their work with the Maasai in the London Marathon. With the merge, Greenforce focused on science-oriented conservation projects whilst Trekforce continued to promote safe and adventurous expeditions.
In early 2009, Trekforce is set to become an integral organisation within Gapforce.
Countries of Operation
Belize
Papua New Guinea
Ecuador
Nepal
Morocco
Thailand
India
Vietnam
Cambodia
Achievements
Trekforce is an official Belizean NGO and has been given part of its rainforest to sustain.
Over the years, Trekforce has worked with many film and television crews, including Ben Fogle in his TV series Extreme Dreams, Jack Osborne on Adrenalin Junkie and Bruce Parry on The Tribe. Trekforce provides important TV and film logistics, especially in remote settings.
Trekforce has completed over 200 projects, been responsible for the creation of over 100 national parks and helped set up significant rainforest, archeological and marine research centres.
History
Wandy Swales was the inspiration and spirit behind Trekforce. He was one of the late and great original explorers. Like every explorer he inspired those he came into contact with. Wandy also co-led Operation Drake (the precursor to Operation Raleigh). Realising the great work that expeditions can do for the host country as well as the participant, Wandy founded Swale Treks and started leading true adventurous expeditions in the mid 1980s exclusively to Indonesia, where at the time many of the 30,000 islands were uninhabited.
Swale Treks turned into the charity: The International Scientific Support Trust in 1990. This in turn became Trekforce Expeditions to reflect the changing nature of project-based expeditions. The early 1990s saw an increase in the popularity of expeditions. Trekforce has always placed an important emphasis on leadership and their staff have included Bruce Parry, Doug Warner, Ed Swales, Damian Taylor, Corrin Adshead, Lizzy Ellis and Steve Oliver who were all involved in carrying on the great work from Wandy and his fellow supporters. Trekforce Expeditions was continued by Rob Murray John, who then set up Trekforce Worldwide to carry on the legacy of Trekforce Expeditions.
Trekforce Expeditions was a UK-registered Youth Development Charity (No. 1005452) running from 1990 to 2006, which ran two-month jungle expeditions in places such as Belize, Borneo and Guyana where it conducted various conservation projects. The volunteers were predominately from the UK, aged 17-25, with the aim being personal development whilst contributing to remote infrastructure projects in these countries. It is now a limited company and still promotes the original environmental and adventurous principles that it was founded on.
In February 2008, Trekforce was acquired by Greenforce, another gap year company that places a strong emphasis on conservation and the environment. Greenforce specialises in marine conservation and terrestrial projects. In April, they became well known for their work with the Maasai in the London Marathon. With the merge, Greenforce focused on science-oriented conservation projects whilst Trekforce continued to promote safe and adventurous expeditions.
In early 2009, Trekforce is set to become an integral organisation within Gapforce.
Countries of Operation
Belize
Papua New Guinea
Ecuador
Nepal
Morocco
Thailand
India
Vietnam
Cambodia
Achievements
Trekforce is an official Belizean NGO and has been given part of its rainforest to sustain.
Over the years, Trekforce has worked with many film and television crews, including Ben Fogle in his TV series Extreme Dreams, Jack Osborne on Adrenalin Junkie and Bruce Parry on The Tribe. Trekforce provides important TV and film logistics, especially in remote settings.
Trekforce has completed over 200 projects, been responsible for the creation of over 100 national parks and helped set up significant rainforest, archeological and marine research centres.
Tigris-Euphrates river system
The Tigris-Euphrates river system is part of the Tigris-Euphrates alluvial salt marsh ecoregion of the Middle East, and is characterized by two large rivers, the Tigris and Euphrates. The rivers have several small tributaries which feed into shallow freshwater lakes, swamps, and marshes, all surrounded by desert. The hydrology of these vast marshes is extremely important to the ecology of the entire upper Persian Gulf. Historically, the area is known as Mesopotamia. As part of the larger Fertile Crescent, it saw the earliest emergence of literate urban civilization in the Uruk period, for which reason it is often dubbed the "Cradle of Civilization".
In the 1980s this ecoregion was put in grave danger as the Iran–Iraq War raged within its boundaries. It also faced one of the massive economic-environmental crimes in modern history: the destruction of Iraq's wetlands.
General description
The general climate is subtropical, hot and arid. At the northern end of the Persian Gulf is the vast floodplain of the Euphrates, Tigris, and Karun Rivers, featuring huge permanent lakes, marshes, and forest. The aquatic vegetation includes reeds, rushes, and papyrus, which support numerous species. Areas around the Tigris and the Euphrates are very fertile. Marshy land is home to water birds, some stopping here while migrating, and some spending the winter in these marshes living off the lizards, snakes, frogs, and fish. Other animals found in these marshes are water buffalo, two endemic rodent species, antelopes and gazelles and small animals such as the jerboa and several other mammals.
Arabic is the main local language. It is estimated that fewer than 10,000 of the indigenous Marsh Arabs remain.
Ecological threats
Iraq suffers from desertification and soil salination due in large part to thousands of years of agricultural activity. Water is scarce and plant-life sparse. Saddam Hussein's government water control projects have drained most of the inhabited marsh areas east of An Nasiriyah by drying up or diverting streams and rivers. Population of Shi'a Muslims have been displaced. The destruction of the natural habitat poses serious threats to the area's wildlife populations. There are also inadequate supplies of potable water.
Marshlands were a fine and extensive natural wetlands ecosystem. They developed over thousands of years in the Tigris-Euphrates basin and once covered 15–20,000 square kilometers. According to the United Nations Environmental Program and the AMAR Charitable Foundation, between 84% and 90% of the marshes have been destroyed since the 70s. In 1994, 60 percent of the wetlands were destroyed by Saddam Hussein's regime. They were drained to permit military access and greater political control of the native Marsh Arabs. Canals, dykes and dams were built routing the water of the Tigris and Euphrates Rivers around the marshes, instead of allowing water to move slowly through the marshland. After part of the Euphrates was dried up due to re-routing its water to the sea, a dam was built so water could not back up from the Tigris and sustain the former marshland. Some marshlands were burned and buried pipes underground helped to carry away water for quicker drying.
The drying of the marshes lead to the disappearance of the salt-tolerant vegetation, the plankton rich waters that fertilized surrounding soils, 52 native fish species, the wild boar, Red Fox, buffalo and water birds of the marsh habitat.
Conservation
Conservation status : critical/endangered
Protected area :
Endemic species : Basra Reed Warbler (Acrocephalus griseldis), Iraq Babbler (Turdoides altirostris)
Threatened species : Basra Reed Warbler (Acrocephalus griseldis) - ENDANGERED
Extinct species : subspecies of rat and another of otter
In the 1980s this ecoregion was put in grave danger as the Iran–Iraq War raged within its boundaries. It also faced one of the massive economic-environmental crimes in modern history: the destruction of Iraq's wetlands.
General description
The general climate is subtropical, hot and arid. At the northern end of the Persian Gulf is the vast floodplain of the Euphrates, Tigris, and Karun Rivers, featuring huge permanent lakes, marshes, and forest. The aquatic vegetation includes reeds, rushes, and papyrus, which support numerous species. Areas around the Tigris and the Euphrates are very fertile. Marshy land is home to water birds, some stopping here while migrating, and some spending the winter in these marshes living off the lizards, snakes, frogs, and fish. Other animals found in these marshes are water buffalo, two endemic rodent species, antelopes and gazelles and small animals such as the jerboa and several other mammals.
Arabic is the main local language. It is estimated that fewer than 10,000 of the indigenous Marsh Arabs remain.
Ecological threats
Iraq suffers from desertification and soil salination due in large part to thousands of years of agricultural activity. Water is scarce and plant-life sparse. Saddam Hussein's government water control projects have drained most of the inhabited marsh areas east of An Nasiriyah by drying up or diverting streams and rivers. Population of Shi'a Muslims have been displaced. The destruction of the natural habitat poses serious threats to the area's wildlife populations. There are also inadequate supplies of potable water.
Marshlands were a fine and extensive natural wetlands ecosystem. They developed over thousands of years in the Tigris-Euphrates basin and once covered 15–20,000 square kilometers. According to the United Nations Environmental Program and the AMAR Charitable Foundation, between 84% and 90% of the marshes have been destroyed since the 70s. In 1994, 60 percent of the wetlands were destroyed by Saddam Hussein's regime. They were drained to permit military access and greater political control of the native Marsh Arabs. Canals, dykes and dams were built routing the water of the Tigris and Euphrates Rivers around the marshes, instead of allowing water to move slowly through the marshland. After part of the Euphrates was dried up due to re-routing its water to the sea, a dam was built so water could not back up from the Tigris and sustain the former marshland. Some marshlands were burned and buried pipes underground helped to carry away water for quicker drying.
The drying of the marshes lead to the disappearance of the salt-tolerant vegetation, the plankton rich waters that fertilized surrounding soils, 52 native fish species, the wild boar, Red Fox, buffalo and water birds of the marsh habitat.
Conservation
Conservation status : critical/endangered
Protected area :
Endemic species : Basra Reed Warbler (Acrocephalus griseldis), Iraq Babbler (Turdoides altirostris)
Threatened species : Basra Reed Warbler (Acrocephalus griseldis) - ENDANGERED
Extinct species : subspecies of rat and another of otter
Threatened species,IUCN Red List
World Conservation Union
IUCN Red List
The threatened categories (IUCN Red List)
Threatened species are any species (including animals, plants, fungi, etc.) which are vulnerable to extinction in the near future. World Conservation Union (IUCN) is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories: vulnerable, endangered, and critically endangered, depending on the degree to which they are threatened.
Species that are threatened are sometimes characterised by the population dynamics measure of critical depensation, a mathematical measure of biomass related to population growth rate. This quantitative metric is one method of evaluating the degree of endangerment.
Less-than-threatened categories are Near Threatened, Least Concern, and the no longer assigned category of Conservation Dependent. Species which have not been evaluated (NE), or do not have sufficient data (Data Deficient) also are not considered "threatened" by the IUCN.
Although threatened and vulnerable may be used interchangeably when discussing IUCN categories, the term threatened is generally used to refer to the three categories (critically endangered, endangered and vulnerable), while vulnerable is used to refer to the least at risk of those three categories. They may be used interchangeably in most contexts however, as all vulnerable species are threatened species (vulnerable is a category of threatened species); and, as the more at-risk categories of threatened species (namely endangered and critically endangered) must, by definition, also qualify as vulnerable species, all threatened species may also be considered vulnerable.
Threatened species are also referred to as a red-listed species, as they are listed in the IUCN Red List of Threatened Species.
Subspecies, populations and stocks may also be classified as threatened.
IUCN Red List
The threatened categories (IUCN Red List)
Threatened species are any species (including animals, plants, fungi, etc.) which are vulnerable to extinction in the near future. World Conservation Union (IUCN) is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories: vulnerable, endangered, and critically endangered, depending on the degree to which they are threatened.
Species that are threatened are sometimes characterised by the population dynamics measure of critical depensation, a mathematical measure of biomass related to population growth rate. This quantitative metric is one method of evaluating the degree of endangerment.
Less-than-threatened categories are Near Threatened, Least Concern, and the no longer assigned category of Conservation Dependent. Species which have not been evaluated (NE), or do not have sufficient data (Data Deficient) also are not considered "threatened" by the IUCN.
Although threatened and vulnerable may be used interchangeably when discussing IUCN categories, the term threatened is generally used to refer to the three categories (critically endangered, endangered and vulnerable), while vulnerable is used to refer to the least at risk of those three categories. They may be used interchangeably in most contexts however, as all vulnerable species are threatened species (vulnerable is a category of threatened species); and, as the more at-risk categories of threatened species (namely endangered and critically endangered) must, by definition, also qualify as vulnerable species, all threatened species may also be considered vulnerable.
Threatened species are also referred to as a red-listed species, as they are listed in the IUCN Red List of Threatened Species.
Subspecies, populations and stocks may also be classified as threatened.
Tarim Basin
The Tarim Basin (Chinese: 塔里木盆地; pinyin: Tǎlǐmù Péndì; Uyghur: تارىم ئويمانلىقى) is a large endorheic basin occupying an area of more than 400,000 km². It is located in the Xinjiang Uyghur Autonomous Region in China's far west. Its northern boundary is the Tian Shan mountain range and its southern is the Kunlun Mountains on the northern edge of the Tibetan Plateau. The Taklamakan Desert dominates much of the basin. The area is sparsely settled by the Uyghurs, other Turkic peoples and Tajiks.
Geology
The Tarim Basin is the remains of an ancient microcontinent that amalgamated with the growing Eurasian continent during the Carboniferous to Permian. At present, deformation around the margins of the basin is resulting in the microcontinental crust being underthrust beneath the Tien Shan to the north, and the Kunlun Shan to the south.
The Tarim Basin is believed to contain large reserves of petroleum and natural gas, with methane comprising over 70 percent of the natural gas reserve, up to 9.2 bb. A thick succession of Paleozoic, Mesozoic and Cenozoic rocks occupy the central parts of the basin, locally exceeding thicknesses of 15 km. The source rocks of oil and gas tend to be Permian mudstones. Below this level is a complex Precambrian basement believed to be the remnants of the original Tarim microplate, which accrued to the growing Eurasian continent in Carboniferous time. The snow on K2, the second highest mountain in the world, flows into glaciers which move down the valleys to melt. The melted water forms rivers which flow down the mountains and into the Tarim Basin, never reaching the sea. Surrounded by desert, some rivers feed the oases where the water is used for irrigation while others flow to salt lakes and marshes.
History
The Silk Road, a series of trade routes through regions of Asia, splits into two routes: the North Silk Road along the northern edge and another along the southern edge of the Taklamakan Desert in the basin. A middle route was deserted in the sixth century. The southern trackway includes the oasis towns of Yarkand, Niya, Pishan, Marin and Khotan. The key oasis towns along the northern route are Aksu, Korla, Turfan, Gaochang and Loulan. Other key towns include Kashgar in the South-West, Kuqa in the North, and Dunhuang in the East. Formerly the Tocharian languages were spoken in the Tarim Basin. They were the easternmost of the Indo-European languages. The Chinese name "Yuezhi" (Chinese 月氏; Wade-Giles: Yüeh-Chih) denoted an ancient Central Asian people settled in modern eastern Tarim Basin, who, vanquished by the Xiongnu, later migrated southward in order to form the Kushan Empire, which was centred on Afghanistan/Pakistan, but also extended into northern India.
The Han Chinese managed to take control of the Tarim Basin from the Xiongnu at the end of the 1st century under the leadership of general Ban Chao (32 - 102).
The powerful Kushans expanded back into the Tarim Basin in the 1st-2nd centuries AD, where they established a kingdom in Kashgar and competed for control of the area with nomads and Chinese forces. They introduced the Brahmi script, the Indian Prakrit language for administration, and Buddhism, playing a central role in the Silk Road transmission of Buddhism to Eastern Asia.
Lop Nur, a saline marshy depression at the east end of the Tarim Basin, is a nuclear test site for the People's Republic of China. The Tarim River empties into the Lop Nur.
Archaeology
Although archaeological findings are of interest in the Tarim Basin, the prime impetus for exploration was petroleum and natural gas. Recently research developed fine-grained analysis at the ancient oasis of Niya on the Silk Road; moreover, the work led to significant findings of remains of wattle hamlets and daub structures as well as farm land, orchards, vineyards, irrigation pools and bridges. The oasis at Niya preserves the ancient landscape. Here also have been found hundreds of 3rd and 4th century wooden accounting tablets at several settlements across the oasis. These texts are in the Gāndhārī language script native to today's Pakistan and Afghanistan. The texts are legal documents such as tax lists, and contracts containing detailed information pertaining to the administration of daily affairs.
Additional excavations have unearthed tombs with mummies, tools, ceramic works, painted pottery and other artistic artifacts. Such diversity was encouraged by the cultural contacts resulting from this area's position on the Silk Road. Early Buddhist sculptures and murals excavated at Miran show artistic similarities to the traditions of Central Asia and North India and stylistic aspects of paintings found there suggest that Miran had a direct connection with the West, specifically Rome and its provinces.
Geology
The Tarim Basin is the remains of an ancient microcontinent that amalgamated with the growing Eurasian continent during the Carboniferous to Permian. At present, deformation around the margins of the basin is resulting in the microcontinental crust being underthrust beneath the Tien Shan to the north, and the Kunlun Shan to the south.
The Tarim Basin is believed to contain large reserves of petroleum and natural gas, with methane comprising over 70 percent of the natural gas reserve, up to 9.2 bb. A thick succession of Paleozoic, Mesozoic and Cenozoic rocks occupy the central parts of the basin, locally exceeding thicknesses of 15 km. The source rocks of oil and gas tend to be Permian mudstones. Below this level is a complex Precambrian basement believed to be the remnants of the original Tarim microplate, which accrued to the growing Eurasian continent in Carboniferous time. The snow on K2, the second highest mountain in the world, flows into glaciers which move down the valleys to melt. The melted water forms rivers which flow down the mountains and into the Tarim Basin, never reaching the sea. Surrounded by desert, some rivers feed the oases where the water is used for irrigation while others flow to salt lakes and marshes.
History
The Silk Road, a series of trade routes through regions of Asia, splits into two routes: the North Silk Road along the northern edge and another along the southern edge of the Taklamakan Desert in the basin. A middle route was deserted in the sixth century. The southern trackway includes the oasis towns of Yarkand, Niya, Pishan, Marin and Khotan. The key oasis towns along the northern route are Aksu, Korla, Turfan, Gaochang and Loulan. Other key towns include Kashgar in the South-West, Kuqa in the North, and Dunhuang in the East. Formerly the Tocharian languages were spoken in the Tarim Basin. They were the easternmost of the Indo-European languages. The Chinese name "Yuezhi" (Chinese 月氏; Wade-Giles: Yüeh-Chih) denoted an ancient Central Asian people settled in modern eastern Tarim Basin, who, vanquished by the Xiongnu, later migrated southward in order to form the Kushan Empire, which was centred on Afghanistan/Pakistan, but also extended into northern India.
The Han Chinese managed to take control of the Tarim Basin from the Xiongnu at the end of the 1st century under the leadership of general Ban Chao (32 - 102).
The powerful Kushans expanded back into the Tarim Basin in the 1st-2nd centuries AD, where they established a kingdom in Kashgar and competed for control of the area with nomads and Chinese forces. They introduced the Brahmi script, the Indian Prakrit language for administration, and Buddhism, playing a central role in the Silk Road transmission of Buddhism to Eastern Asia.
Lop Nur, a saline marshy depression at the east end of the Tarim Basin, is a nuclear test site for the People's Republic of China. The Tarim River empties into the Lop Nur.
Archaeology
Although archaeological findings are of interest in the Tarim Basin, the prime impetus for exploration was petroleum and natural gas. Recently research developed fine-grained analysis at the ancient oasis of Niya on the Silk Road; moreover, the work led to significant findings of remains of wattle hamlets and daub structures as well as farm land, orchards, vineyards, irrigation pools and bridges. The oasis at Niya preserves the ancient landscape. Here also have been found hundreds of 3rd and 4th century wooden accounting tablets at several settlements across the oasis. These texts are in the Gāndhārī language script native to today's Pakistan and Afghanistan. The texts are legal documents such as tax lists, and contracts containing detailed information pertaining to the administration of daily affairs.
Additional excavations have unearthed tombs with mummies, tools, ceramic works, painted pottery and other artistic artifacts. Such diversity was encouraged by the cultural contacts resulting from this area's position on the Silk Road. Early Buddhist sculptures and murals excavated at Miran show artistic similarities to the traditions of Central Asia and North India and stylistic aspects of paintings found there suggest that Miran had a direct connection with the West, specifically Rome and its provinces.
Syngas fermentation,ethanol, butanol, acetic acid, butyric acid, Clostridium ljungdahlii, Clostridium autoethanogenum, Eurobacterium limosum
Syngas fermentation, also known as synthesis gas fermentation, is a microbial process. In this process, a mixture of hydrogen, carbon monoxide, and carbon dioxide, known as syngas, is used as carbon and energy sources, and then converted into fuel and chemicals by microorganisms. The main products of syngas fermentation include ethanol, butanol, acetic acid, butyric acid, and methane.
There are several microorganisms which can produce fuels and chemicals by syngas utilization. These microorganisms are mostly known as acetogens including Clostridium ljungdahlii, Clostridium autoethanogenum, Eurobacterium limosum, Clostridium carboxidivorans P7, Peptostreptococcus products, and Butyribacterium methylotrophicum.
Syngas fermentation process has advantages over a chemical process since it takes places at lower temperature and pressure, has higher reaction specificity, tolerates higher amounts of sulfur compounds, and does not require a specific CO:H2. On the other hand, syngas fermentation has limitations such as:
* Gas-liquid mass transfer limitation
* Low volumetric productivity, and
* Inhibition of organisms.
There are several microorganisms which can produce fuels and chemicals by syngas utilization. These microorganisms are mostly known as acetogens including Clostridium ljungdahlii, Clostridium autoethanogenum, Eurobacterium limosum, Clostridium carboxidivorans P7, Peptostreptococcus products, and Butyribacterium methylotrophicum.
Syngas fermentation process has advantages over a chemical process since it takes places at lower temperature and pressure, has higher reaction specificity, tolerates higher amounts of sulfur compounds, and does not require a specific CO:H2. On the other hand, syngas fermentation has limitations such as:
* Gas-liquid mass transfer limitation
* Low volumetric productivity, and
* Inhibition of organisms.
Sylvia's Meadow,SSSI,Autumn Ladies'-tresses, Sneezewort, Yellow Rattle and Bird's Foot Trefoil.
Sylvia's Meadow (SSSI) is a nature reserve owned and managed by Cornwall Wildlife Trust. It is a herb rich, 5 hectare site situated near Gunnislake, in East Cornwall, United Kingdom.
It is famed for the orchids that grow there, which include the Lesser Butterfly Orchid and Heath Spotted Orchid.
Sylvia's Meadow (SSSI) is an example of unimproved herb-rich pasture land containing some rare plant species. During World War II a US military camp was situated in Sylia's Meadow and since then the land has been left unploughed and unimproved. In this respect Sylvia's Meadow is unique to Cornwall.
Other species found here include: Autumn Ladies'-tresses, Sneezewort, Yellow Rattle and Bird's Foot Trefoil.
Butterflies that may be seen include The Wall, Orange Tip, Dingy Skipper and the Common Blue. Reptile sightings include the Common Lizard and the Slow Worm.
During World War II, Sylvia's Meadow military camp housed only white American armed forces personnel. Black American airmen were billeted in an adjacent field.
The reserve is named after a previous owner's daughter.
It is famed for the orchids that grow there, which include the Lesser Butterfly Orchid and Heath Spotted Orchid.
Sylvia's Meadow (SSSI) is an example of unimproved herb-rich pasture land containing some rare plant species. During World War II a US military camp was situated in Sylia's Meadow and since then the land has been left unploughed and unimproved. In this respect Sylvia's Meadow is unique to Cornwall.
Other species found here include: Autumn Ladies'-tresses, Sneezewort, Yellow Rattle and Bird's Foot Trefoil.
Butterflies that may be seen include The Wall, Orange Tip, Dingy Skipper and the Common Blue. Reptile sightings include the Common Lizard and the Slow Worm.
During World War II, Sylvia's Meadow military camp housed only white American armed forces personnel. Black American airmen were billeted in an adjacent field.
The reserve is named after a previous owner's daughter.
Svalbard Global Seed Vault,Global Crop Diversity Trust (GCDT),Nordic Gene Bank,Nordic Genetic Resource Center (NORDGEN)
The Svalbard Global Seed Vault is a secure seedbank located on the Norwegian island of Spitsbergen near the town of Longyearbyen in the remote Arctic Svalbard archipelago. The facility was established to preserve a wide variety of plant seeds from locations worldwide in an underground cavern. The Seed Vault holds duplicate samples, or "spare" copies, of seeds held in genebanks worldwide. The Seed Vault will provide insurance against the loss of seeds in genebanks, as well as a refuge for seeds in the case of large scale regional or global crises. The island of Spitsbergen is about 1,120 kilometres (700 mi) from the North Pole.
The Seed Vault is managed under terms spelled out in a tripartite agreement between the Norwegian government, the Global Crop Diversity Trust (GCDT) and the Nordic Genetic Resource Center (previously named the Nordic Gene Bank, a cooperative effort of the Nordic countries under the Nordic Council of Ministers).
The GCDT has played a key role in the planning of the Seed Vault and is coordinating shipments of seed samples to the Vault in conjunction with the Nordic Genetic Resource Center. The Trust will provide most of the annual operating costs for the facility, and has set aside endowment funds to do so, while the Norwegian government will finance upkeep of the structure itself. With support from the Bill & Melinda Gates Foundation and other donors, the GCDT is assisting selected genebanks in developing countries as well as the international agricultural research centers in packaging and shipping seeds to the Seed Vault. An International Advisory Council is being established to provide guidance and advice. It will include representatives from the FAO, the CGIAR, the International Treaty on Plant Genetic Resources and other institutions.
Construction of the Seed Vault, which cost approximately 45 million Norwegian Kroner ($9 million), was funded entirely by the Government of Norway. Storage of seeds in the Seed Vault is free of charge. Operational costs will be paid by Norway and the Global Crop Diversity Trust. The primary funders of the Trust are the Bill & Melinda Gates Foundation, the United Kingdom, Norway, Australia, Switzerland and Sweden, though funding has been received from a wide variety of sources including four developing countries: Brazil, Colombia, Ethiopia, and India.
History
The Nordic Gene Bank has stored a backup of Nordic plant germplasm as frozen seeds in an abandoned coal mine at Svalbard since 1984. The Nordic Gene Bank (NGB) has deposited more than 10,000 seed samples of more than 2,000 cultivars of 300 different species over the years. In addition, seed samples from southern Africa (SADC) have been safely duplicated with the Nordic collection for some years. Both the Nordic and African collections are expected be transferred to the Svalbard Global Seed Vault in the future. Since January 1, 2008 the Nordic Gene Bank is an integrated part of the newly formed Nordic Genetic Resource Center (NORDGEN).
Construction
The prime ministers of Norway, Sweden, Finland, Denmark, and Iceland participated in a ceremonial "laying of the first stone" on 19 June 2006.
The seedbank is constructed 120 metres (390 ft) inside a sandstone mountain at Svalbard on Spitsbergen Island. The bank employs a number of robust security systems. Seeds are packaged in special four-ply packets and heat sealed to exclude moisture. The facility is managed by the Nordic Genetic Resource Center, though there are no permanent staff on-site.
Spitsbergen was considered ideal due to its lack of tectonic activity and its permafrost, which will aid preservation. The location 130 metres (430 ft) above sea level will ensure that the site remains dry even if the icecaps melt. Locally mined coal provides power for refrigeration units that further cool the seeds to the internationally-recommended standard −18 °C (−0 °F). Even if the equipment fails, at least several weeks will elapse before the temperature rises to the −3 °C (30 °F) of the surrounding sandstone bedrock.
Prior to construction, a feasibility study determined that the vault could preserve seeds from most major food crops for hundreds of years. Some seeds, including those of important grains, could survive far longer, possibly thousands of years.
The Svalbard Global Seed Vault opened officially on February 26, 2008. Approximately 1.5 million distinct seed samples of agricultural crops are thought to exist. The variety and volume of seeds stored will depend on the number of countries participating – the facility has a capacity to conserve 4.5 million. The first seeds arrived in January 2008. Five percent of the seeds in the Vault, about 18,000 samples with 500 seeds each, come from the Centre for Genetic Resources of the Netherlands (CGN), part of Wageningen University, Netherlands.
Mission
The Svalbard Global Seed Vault's mission is to provide a safety net against accidental loss of diversity in traditional genebanks. While the popular press has emphasized its possible utility in the event of a major regional or global catastrophe, it will certainly be more frequently accessed when genebanks lose samples due to mismanagement, accident, equipment failures, funding cuts and natural disasters. Such events occur with some regularity. In recent years, some national genebanks have also been destroyed by war and civil strife. There are some 1,400 crop diversity collections around the world, but many are in politically unstable or environmentally threatened nations.
Access to seeds
The seed samples stored in the Seed Vault are copies of samples stored in the depositing genebanks. Researchers, plant breeders and other groups wishing to access seed samples cannot do so through the Seed Vault; instead they must request samples from the depositing genebanks. The samples stored in the genebanks will, in most cases, be accessible in accordance with the terms and conditions of the International Treaty on Plant Genetic Resources for Food and Agriculture, approved by 118 countries/Parties.
The Seed Vault functions like a safety deposit box in a bank. The bank owns the building and the depositor owns the contents of his or her box. The Government of Norway owns the facility and the depositing genebanks own the seeds they send. The deposit of samples in Svalbard does not constitute a legal transfer of genetic resources. In genebank terminology this is called a "black box" arrangement. Each depositor signs a Deposit Agreement with NORDGEN, acting on behalf of Norway. The Agreement makes clear that Norway does not claim ownership over the deposited samples and that ownership remains with the depositor, who has the sole right of access to those materials in the Seed Vault. No one has access to anyone else’s seeds from the Seed Vault.
Controversy
It has been alleged that there has been some controversy over private involvement in the Svalbard Global Seed Vault. In fact, the Vault was unanimously welcomed at the United Nations when proposed by Norway. The Government of Norway funded the construction of the Vault in its entirety and will continue to fund its maintenance. The Global Crop Diversity Trust funds the operation and management of the facility, and has funded the transport of seeds from genebanks in developing countries and from international genebanks to the Arctic. For the first three years of the Vault’s existence, the transport of seeds from international collections and developing countries has been made possible through a partnership between the Trust and the United Nations Foundation funded by the Bill & Melinda Gates Foundation.
All seeds stored in the Seed Vault remain the property of the country or institution that sent them. There is no change of ownership. Neither the managers of the Seed Vault, Norway, the Trust, nor anyone else has any right even to open the boxes in which the seeds arrive and are stored. Seeds are available only to the depositors to restore samples they have lost themselves. Information about which countries have sent seeds, and the seeds which are already stored in the Vault, is all public. For a list of depositors to the Svalbard Global Seed Vault, see the Seed Vault online database managed by NORDGEN. For the complete list of donors to the Global Crop Diversity Trust.
The Seed Vault is managed under terms spelled out in a tripartite agreement between the Norwegian government, the Global Crop Diversity Trust (GCDT) and the Nordic Genetic Resource Center (previously named the Nordic Gene Bank, a cooperative effort of the Nordic countries under the Nordic Council of Ministers).
The GCDT has played a key role in the planning of the Seed Vault and is coordinating shipments of seed samples to the Vault in conjunction with the Nordic Genetic Resource Center. The Trust will provide most of the annual operating costs for the facility, and has set aside endowment funds to do so, while the Norwegian government will finance upkeep of the structure itself. With support from the Bill & Melinda Gates Foundation and other donors, the GCDT is assisting selected genebanks in developing countries as well as the international agricultural research centers in packaging and shipping seeds to the Seed Vault. An International Advisory Council is being established to provide guidance and advice. It will include representatives from the FAO, the CGIAR, the International Treaty on Plant Genetic Resources and other institutions.
Construction of the Seed Vault, which cost approximately 45 million Norwegian Kroner ($9 million), was funded entirely by the Government of Norway. Storage of seeds in the Seed Vault is free of charge. Operational costs will be paid by Norway and the Global Crop Diversity Trust. The primary funders of the Trust are the Bill & Melinda Gates Foundation, the United Kingdom, Norway, Australia, Switzerland and Sweden, though funding has been received from a wide variety of sources including four developing countries: Brazil, Colombia, Ethiopia, and India.
History
The Nordic Gene Bank has stored a backup of Nordic plant germplasm as frozen seeds in an abandoned coal mine at Svalbard since 1984. The Nordic Gene Bank (NGB) has deposited more than 10,000 seed samples of more than 2,000 cultivars of 300 different species over the years. In addition, seed samples from southern Africa (SADC) have been safely duplicated with the Nordic collection for some years. Both the Nordic and African collections are expected be transferred to the Svalbard Global Seed Vault in the future. Since January 1, 2008 the Nordic Gene Bank is an integrated part of the newly formed Nordic Genetic Resource Center (NORDGEN).
Construction
The prime ministers of Norway, Sweden, Finland, Denmark, and Iceland participated in a ceremonial "laying of the first stone" on 19 June 2006.
The seedbank is constructed 120 metres (390 ft) inside a sandstone mountain at Svalbard on Spitsbergen Island. The bank employs a number of robust security systems. Seeds are packaged in special four-ply packets and heat sealed to exclude moisture. The facility is managed by the Nordic Genetic Resource Center, though there are no permanent staff on-site.
Spitsbergen was considered ideal due to its lack of tectonic activity and its permafrost, which will aid preservation. The location 130 metres (430 ft) above sea level will ensure that the site remains dry even if the icecaps melt. Locally mined coal provides power for refrigeration units that further cool the seeds to the internationally-recommended standard −18 °C (−0 °F). Even if the equipment fails, at least several weeks will elapse before the temperature rises to the −3 °C (30 °F) of the surrounding sandstone bedrock.
Prior to construction, a feasibility study determined that the vault could preserve seeds from most major food crops for hundreds of years. Some seeds, including those of important grains, could survive far longer, possibly thousands of years.
The Svalbard Global Seed Vault opened officially on February 26, 2008. Approximately 1.5 million distinct seed samples of agricultural crops are thought to exist. The variety and volume of seeds stored will depend on the number of countries participating – the facility has a capacity to conserve 4.5 million. The first seeds arrived in January 2008. Five percent of the seeds in the Vault, about 18,000 samples with 500 seeds each, come from the Centre for Genetic Resources of the Netherlands (CGN), part of Wageningen University, Netherlands.
Mission
The Svalbard Global Seed Vault's mission is to provide a safety net against accidental loss of diversity in traditional genebanks. While the popular press has emphasized its possible utility in the event of a major regional or global catastrophe, it will certainly be more frequently accessed when genebanks lose samples due to mismanagement, accident, equipment failures, funding cuts and natural disasters. Such events occur with some regularity. In recent years, some national genebanks have also been destroyed by war and civil strife. There are some 1,400 crop diversity collections around the world, but many are in politically unstable or environmentally threatened nations.
Access to seeds
The seed samples stored in the Seed Vault are copies of samples stored in the depositing genebanks. Researchers, plant breeders and other groups wishing to access seed samples cannot do so through the Seed Vault; instead they must request samples from the depositing genebanks. The samples stored in the genebanks will, in most cases, be accessible in accordance with the terms and conditions of the International Treaty on Plant Genetic Resources for Food and Agriculture, approved by 118 countries/Parties.
The Seed Vault functions like a safety deposit box in a bank. The bank owns the building and the depositor owns the contents of his or her box. The Government of Norway owns the facility and the depositing genebanks own the seeds they send. The deposit of samples in Svalbard does not constitute a legal transfer of genetic resources. In genebank terminology this is called a "black box" arrangement. Each depositor signs a Deposit Agreement with NORDGEN, acting on behalf of Norway. The Agreement makes clear that Norway does not claim ownership over the deposited samples and that ownership remains with the depositor, who has the sole right of access to those materials in the Seed Vault. No one has access to anyone else’s seeds from the Seed Vault.
Controversy
It has been alleged that there has been some controversy over private involvement in the Svalbard Global Seed Vault. In fact, the Vault was unanimously welcomed at the United Nations when proposed by Norway. The Government of Norway funded the construction of the Vault in its entirety and will continue to fund its maintenance. The Global Crop Diversity Trust funds the operation and management of the facility, and has funded the transport of seeds from genebanks in developing countries and from international genebanks to the Arctic. For the first three years of the Vault’s existence, the transport of seeds from international collections and developing countries has been made possible through a partnership between the Trust and the United Nations Foundation funded by the Bill & Melinda Gates Foundation.
All seeds stored in the Seed Vault remain the property of the country or institution that sent them. There is no change of ownership. Neither the managers of the Seed Vault, Norway, the Trust, nor anyone else has any right even to open the boxes in which the seeds arrive and are stored. Seeds are available only to the depositors to restore samples they have lost themselves. Information about which countries have sent seeds, and the seeds which are already stored in the Vault, is all public. For a list of depositors to the Svalbard Global Seed Vault, see the Seed Vault online database managed by NORDGEN. For the complete list of donors to the Global Crop Diversity Trust.
Subalpine,krummholz
Trees in subalpine zone often become krummholz (crooked wood, stunted and twisted). At treeline, tree seedlings may germinate on the lee side of rocks and grow only as high as the rock provides wind protection. Further growth is more horizontal than vertical, and additional rooting may occur where branches contact the soil. The resulting low growth of dense trees is called krummholz. Snow cover may protect krummholz trees during the winter, but branches higher than wind-shelters or snow cover are usually destroyed. Well-established krummholz trees may be several hundred to a thousand years old.
Sturt's Stony Desert
Sturt's Stony Desert is an area in the north-east of South Australia, named by Charles Sturt in 1844, whilst trying to reach the exact centre of Australia. The stones caused his horses to limp and wore down the hooves of the cattle and sheep which Sturt had taken on the expedition.
The larger Simpson Desert is located to the west and the Strzelecki Desert is to the south east. To the south west of Sturt's Stony Desert is the Tirari Desert. The Birdsville Track is a route between Marree in South Australia and Birdsville in Queensland.
The larger Simpson Desert is located to the west and the Strzelecki Desert is to the south east. To the south west of Sturt's Stony Desert is the Tirari Desert. The Birdsville Track is a route between Marree in South Australia and Birdsville in Queensland.
Stewart Island/Rakiura,Te Punga o Te Waka a Maui,Te Rakiura a Te Rakitamau,Te Ura o Te Rakitamau
Stewart Island/Rakiura
Stewart Island/Rakiura is the third-largest island of New Zealand. It lies 30 kilometres (19 mi) south of South Island, across Foveaux Strait. Its permanent population is slightly fewer than 400 people, most of whom live in the settlement of Oban.
History and naming
Captain Cook was the first European to sight the island in 1770, but he thought it was part of the South Island so he named it South Cape. The island was named for William W. Stewart who was first officer on the ship Pegasus, which visited from Port Jackson (Sydney), Australia, in 1809 on a sealing expedition. Stewart charted the large south eastern harbour which now bears the ship's name (Port Pegasus), and determined the northern points of the island, proving that it was an island. He made three further visits to the island from the 1820s to the 1840s. The original Maori name, Te Punga o Te Waka a Maui, positions Stewart Island/Rakiura firmly at the heart of Maori mythology. Translated as The Anchor Stone of Maui’s Canoe, it refers to the part played by the island in the legend of Maui and his crew, who from their canoe, the South Island, caught and raised the great fish, North Island.
Rakiura is the more commonly known and used Maori name. It is usually translated as Glowing Skies, possibly a reference to the sunsets for which it is famous or for the Aurora Australis, the southern lights that are a phenomenon of southern latitudes.
For some, Rakiura is the abbreviated version of Te Rakiura a Te Rakitamau, translated as "great blush of Rakitamau", in reference to the latter's embarrassment when refused the hand in marriage of not one, but two daughters, of an island chief. According to Maori legend, a chief on the island named Te Rakitamau was married to a young woman who became terminally ill and implored him to marry her cousin after she died. Te Rakitamau paddled across Te Moana Tapokopoko a Tawhiki (Foveaux Strait) to South Island where the cousin lived, only to discover she was recently married. He blushed with embarrassment so the island was called Te Ura o Te Rakitamau.
In 1841, the island was established as one of the three Provinces of New Zealand, and was named New Leinster. However, the province existed on paper only and was abolished after only five years, and with the passing of the New Zealand Constitution Act 1846 the province became part of New Munster, which entirely included South Island. When New Munster was abolished in 1853, Stewart Island became part of Otago Province until 1861 when Southland Province split from Otago. In 1876 the provinces were abolished altogether.
Geography
The island has an area of 1,746 km². The north is dominated by the swampy valley of the Freshwater River. The river rises close to the northwestern coast and flows southeastwards into the large indentation of Paterson Inlet. The highest peak is Mt. Anglem, close to the northern coast, at a height of 979 metres (3,210 ft). It is one of the peaks in a rim of ridges that surround the Freshwater Valley.
The southern half is more uniformly undulating, rising to a ridge that runs south from the valley of the Rakeahua River, which also flows into Paterson Inlet. The southernmost point in this ridge is Mt. Allen, at 750 metres (2,500 ft). In the southeast the land is somewhat lower, and is drained by the valleys of the Toitoi River, Lords River, and Heron River. South West Cape on this island is the southernmost point of the main islands of New Zealand.
Mason Bay, on the west side, is notable as a long sandy beach on an island where beaches are typically far more rugged. One suggestion is that the bay was formed in the aftershock of a meteoric impact in the Tasman Sea.
Three large and numerous small islands lie around the coast. Notable among these are Ruapuke Island, in Foveaux Strait 32 kilometres (20 mi) northeast of Oban; Codfish Island, close to the northwest shore; and Big South Cape Island, off the southwestern tip. The Titi/ Muttonbird Islands group are between Stewart Island/ Rakiura and Ruapuke Island, around Big South Cape Island, and off the southeastern coast. Other islands of interest include Bench Island, Native Island, and Ulva Island, all close to the mouth of Paterson Inlet, and Pearl Island, Anchorage Island, and Noble Island, close to Port Pegasus in the southwest.
Two groups of tiny above-water rocks south of Stewart Island/Rakiura are geographically part of New Zealands: North Trap, a reef of above and below-water rocks at [show location on an interactive map] 47°22′S 167°55′E / 47.367°S 167.917°E / -47.367; 167.917 (North Trap reef) fronts the southern shore, about 28.2 kilometres (17.5 mi) southwest by south of the mouth of the Lords River. A 1.5 metres (4.9 ft) high rock near the western end and a 0.9 metres (3.0 ft) high rock near the eastern end give it the appearance of an overturned boat. South Trap, a reef of above-water rocks 1.2 metres (3.9 ft) to 1.8 metres (5.9 ft) high and below-water rocks at [show location on an interactive map] 47°32′S 167°50′E / 47.533°S 167.833°E / -47.533; 167.833 (South Trap reef), lies about 16.9 kilometres (10.5 mi) south by west of North Trap.
Geo-magnetic anomaly
Owing to an anomaly in the magnetic latitude contours, this location is well placed for observing Aurora australis.
Stewart Island/Rakiura is the third-largest island of New Zealand. It lies 30 kilometres (19 mi) south of South Island, across Foveaux Strait. Its permanent population is slightly fewer than 400 people, most of whom live in the settlement of Oban.
History and naming
Captain Cook was the first European to sight the island in 1770, but he thought it was part of the South Island so he named it South Cape. The island was named for William W. Stewart who was first officer on the ship Pegasus, which visited from Port Jackson (Sydney), Australia, in 1809 on a sealing expedition. Stewart charted the large south eastern harbour which now bears the ship's name (Port Pegasus), and determined the northern points of the island, proving that it was an island. He made three further visits to the island from the 1820s to the 1840s. The original Maori name, Te Punga o Te Waka a Maui, positions Stewart Island/Rakiura firmly at the heart of Maori mythology. Translated as The Anchor Stone of Maui’s Canoe, it refers to the part played by the island in the legend of Maui and his crew, who from their canoe, the South Island, caught and raised the great fish, North Island.
Rakiura is the more commonly known and used Maori name. It is usually translated as Glowing Skies, possibly a reference to the sunsets for which it is famous or for the Aurora Australis, the southern lights that are a phenomenon of southern latitudes.
For some, Rakiura is the abbreviated version of Te Rakiura a Te Rakitamau, translated as "great blush of Rakitamau", in reference to the latter's embarrassment when refused the hand in marriage of not one, but two daughters, of an island chief. According to Maori legend, a chief on the island named Te Rakitamau was married to a young woman who became terminally ill and implored him to marry her cousin after she died. Te Rakitamau paddled across Te Moana Tapokopoko a Tawhiki (Foveaux Strait) to South Island where the cousin lived, only to discover she was recently married. He blushed with embarrassment so the island was called Te Ura o Te Rakitamau.
In 1841, the island was established as one of the three Provinces of New Zealand, and was named New Leinster. However, the province existed on paper only and was abolished after only five years, and with the passing of the New Zealand Constitution Act 1846 the province became part of New Munster, which entirely included South Island. When New Munster was abolished in 1853, Stewart Island became part of Otago Province until 1861 when Southland Province split from Otago. In 1876 the provinces were abolished altogether.
Geography
The island has an area of 1,746 km². The north is dominated by the swampy valley of the Freshwater River. The river rises close to the northwestern coast and flows southeastwards into the large indentation of Paterson Inlet. The highest peak is Mt. Anglem, close to the northern coast, at a height of 979 metres (3,210 ft). It is one of the peaks in a rim of ridges that surround the Freshwater Valley.
The southern half is more uniformly undulating, rising to a ridge that runs south from the valley of the Rakeahua River, which also flows into Paterson Inlet. The southernmost point in this ridge is Mt. Allen, at 750 metres (2,500 ft). In the southeast the land is somewhat lower, and is drained by the valleys of the Toitoi River, Lords River, and Heron River. South West Cape on this island is the southernmost point of the main islands of New Zealand.
Mason Bay, on the west side, is notable as a long sandy beach on an island where beaches are typically far more rugged. One suggestion is that the bay was formed in the aftershock of a meteoric impact in the Tasman Sea.
Three large and numerous small islands lie around the coast. Notable among these are Ruapuke Island, in Foveaux Strait 32 kilometres (20 mi) northeast of Oban; Codfish Island, close to the northwest shore; and Big South Cape Island, off the southwestern tip. The Titi/ Muttonbird Islands group are between Stewart Island/ Rakiura and Ruapuke Island, around Big South Cape Island, and off the southeastern coast. Other islands of interest include Bench Island, Native Island, and Ulva Island, all close to the mouth of Paterson Inlet, and Pearl Island, Anchorage Island, and Noble Island, close to Port Pegasus in the southwest.
Two groups of tiny above-water rocks south of Stewart Island/Rakiura are geographically part of New Zealands: North Trap, a reef of above and below-water rocks at [show location on an interactive map] 47°22′S 167°55′E / 47.367°S 167.917°E / -47.367; 167.917 (North Trap reef) fronts the southern shore, about 28.2 kilometres (17.5 mi) southwest by south of the mouth of the Lords River. A 1.5 metres (4.9 ft) high rock near the western end and a 0.9 metres (3.0 ft) high rock near the eastern end give it the appearance of an overturned boat. South Trap, a reef of above-water rocks 1.2 metres (3.9 ft) to 1.8 metres (5.9 ft) high and below-water rocks at [show location on an interactive map] 47°32′S 167°50′E / 47.533°S 167.833°E / -47.533; 167.833 (South Trap reef), lies about 16.9 kilometres (10.5 mi) south by west of North Trap.
Geo-magnetic anomaly
Owing to an anomaly in the magnetic latitude contours, this location is well placed for observing Aurora australis.
Stewardship Cessation,Global war,Societal breakdown
Stewardship Cessation is a concept useful in System Engineering. Certain systems remain hazardous for a desirable period after their useful life, and will usually be managed to ensure that the public and the environment is not exposed to the hazard. It is incumbent on the systems designer to consider the outcome should this stewardship be discontinued for any reason, and to design a system which is as robust as possible in the event of stewardship cessation.
The most obvious example is the nuclear industry, and the radioactive waste it generates which will be a hazard for many centuries. In the present era, most high level waste is in still in currently managed facilities, but various methods are being considered for disposal. Most of the proposed disposal methods are designed to put the waste in a place so isolated from the environment that (it is hoped) immediate stewardship cessation would be safe and appropriate. However, many people are more comfortable with systems where the waste is still accessible, so that if there is an unforeseen problem with the disposal method, the waste can still be accessed to rectify the problem. These systems will still require some level of stewardship, but the system designer must consider that this may not be available for the hundreds of years required.
Another example is when Geostationary Communications Satellites reach the end of their useful lives. Stewardship cessation will occur hopefully in a planned manner, where the operator will move the satellite to a somewhat higher orbit to minimise the risk that the satellite will be a collision hazard to other satellites in the geostationary arc (graveyard burn). Unplanned stewardship cessation will occur if telecommand access to the satellite's systems is cut off due to a failure, for instance in the telecommand receivers.
Reasons for stewardship cessation include:
* Illegal or inappropriate disposal by the last user
* Unreasonable budgetary constraints from government or other body
* Cultural change by stewards leading to negligence
* Climate change putting the system beyond reach (under sea or ice)
* Global war
* Other catastrophe leading to very few humans (e.g. epidemic)
* Societal breakdown
* For remotely operated systems, loss of communication with the remote segment of the system.
The most obvious example is the nuclear industry, and the radioactive waste it generates which will be a hazard for many centuries. In the present era, most high level waste is in still in currently managed facilities, but various methods are being considered for disposal. Most of the proposed disposal methods are designed to put the waste in a place so isolated from the environment that (it is hoped) immediate stewardship cessation would be safe and appropriate. However, many people are more comfortable with systems where the waste is still accessible, so that if there is an unforeseen problem with the disposal method, the waste can still be accessed to rectify the problem. These systems will still require some level of stewardship, but the system designer must consider that this may not be available for the hundreds of years required.
Another example is when Geostationary Communications Satellites reach the end of their useful lives. Stewardship cessation will occur hopefully in a planned manner, where the operator will move the satellite to a somewhat higher orbit to minimise the risk that the satellite will be a collision hazard to other satellites in the geostationary arc (graveyard burn). Unplanned stewardship cessation will occur if telecommand access to the satellite's systems is cut off due to a failure, for instance in the telecommand receivers.
Reasons for stewardship cessation include:
* Illegal or inappropriate disposal by the last user
* Unreasonable budgetary constraints from government or other body
* Cultural change by stewards leading to negligence
* Climate change putting the system beyond reach (under sea or ice)
* Global war
* Other catastrophe leading to very few humans (e.g. epidemic)
* Societal breakdown
* For remotely operated systems, loss of communication with the remote segment of the system.
Species translocation,Sitka Spruce ,fallow deer,sweet chestnut,Western Shield
Species translocation is an effective management strategy and important topic in conservation biology. Translocation is the movement of a species, by people, from one area to another. This management tool decreases the risk of extinction by increasing the range of a species, augmenting the numbers in a critical population, or establishing new populations thus reducing the risk of extinction. This improves the level of biodiversity in the ecosystem.
Three types of translocations
The first of three types of translocation is introduction. Introduction is the deliberate or accidental translocation of a species into the wild in areas where it does not occur naturally. Introduction of non-native species occurs for a variety of reasons. Examples are economic gain (Sitka Spruce), improvement of hunting and fishing (fallow deer), ornamentation of roads (rhododendron) or maintenance (sweet chestnut). In the past, translocation introductions of non-native species to ecosystems far outweighed the benefits of them. For example, eucalyptus trees were introduced in California during the Gold Rush as a fast growing timber source. By the early 1900s, however, this did not happen because of early harvesting and the splitting and twisting of cut wood. Now the introduction of non-native eucalyptus, particularly in the Oakland Hills is causing competition among native plants and encroaching on habitat for natural wildlife.
The second of the three types of translocation is re-introduction. Re-introduction is the deliberate or accidental translocation of a species into the wild in areas where it was indigenous at some point, but no longer at the present. Re-introduction is used as a wildlife management tool for the restoration of an original habitat when it has become altered or species have become extinct due to over-collecting, over-harvesting, human persecution, or habitat deterioration.
Lastly, the third type of translocation is re-stocking. Re-stocking is the translocation of an organism into the wild into an area where it is already present. Re-stocking is considered as a conservation strategy where populations have dropped below critical levels and species recovery is questionable due to slow reproductive rates or inbreeding. The World Conservation Union recommends that re-stocking only occur when the causes of population decline have been removed, the area has the capacity to sustain the desired population, and individuals are of the same race as the population into which they are released but not from genetically impoverished or cloned stock.
Trends of translocations
Between 1973 and 1989 an estimated 515 translocations occurred per year in the United States, Canada, New Zealand and Australia. The majority were conducted in the United States. Birds were the most frequently translocated, followed by threatened and endangered species, then non-game species. Of the 261 translocations in the United States reported wild species were most frequently translocated, and the greatest number occurred in the Southeast.
Programs in action today: Western Shield
Western Shield, of Australia, is a nature conservation program which plays an important role in protecting Australia’s native animal population. More importantly, Western Shield also has programs specializing in translocation of endangered and threatened animals. Founded in 1996, it's the most successful wildlife conservation program in Australia and in 2006, it still remains among the largest in the world. The program has already had significant success: three native mammals in Australia – the woylie, quenda and tammar wallaby – have been removed from the threatened species list, many populations of native animals have recovered or been re-established in their former ranges, and the restoration of ecological processes has begun. From 1996 to 2000, Western Shield has taken part of 60 translocations, mostly introductions, comprised of 17 species all over the country on private and interstate lands.
Reasons for failures
Often, when conducting translocation programs, differences in specific habitat types between the source and release sites are not evaluated as long as the release site contains suitable habitat for the species. Translocations could be especially damaging to endangered species citing the failed attempt of Bufo hemiophys baxteri in Wyoming and B. boreas in the Southern Rocky Mountains. For species that have declined over large areas and long periods of time translocations are of little use. Maintaining a large and widely dispersed population of amphibians and other species is the most important aspect of maintaining regional diversity and translocation should only be attempted when a suitable unoccupied habitat exists.
Three types of translocations
The first of three types of translocation is introduction. Introduction is the deliberate or accidental translocation of a species into the wild in areas where it does not occur naturally. Introduction of non-native species occurs for a variety of reasons. Examples are economic gain (Sitka Spruce), improvement of hunting and fishing (fallow deer), ornamentation of roads (rhododendron) or maintenance (sweet chestnut). In the past, translocation introductions of non-native species to ecosystems far outweighed the benefits of them. For example, eucalyptus trees were introduced in California during the Gold Rush as a fast growing timber source. By the early 1900s, however, this did not happen because of early harvesting and the splitting and twisting of cut wood. Now the introduction of non-native eucalyptus, particularly in the Oakland Hills is causing competition among native plants and encroaching on habitat for natural wildlife.
The second of the three types of translocation is re-introduction. Re-introduction is the deliberate or accidental translocation of a species into the wild in areas where it was indigenous at some point, but no longer at the present. Re-introduction is used as a wildlife management tool for the restoration of an original habitat when it has become altered or species have become extinct due to over-collecting, over-harvesting, human persecution, or habitat deterioration.
Lastly, the third type of translocation is re-stocking. Re-stocking is the translocation of an organism into the wild into an area where it is already present. Re-stocking is considered as a conservation strategy where populations have dropped below critical levels and species recovery is questionable due to slow reproductive rates or inbreeding. The World Conservation Union recommends that re-stocking only occur when the causes of population decline have been removed, the area has the capacity to sustain the desired population, and individuals are of the same race as the population into which they are released but not from genetically impoverished or cloned stock.
Trends of translocations
Between 1973 and 1989 an estimated 515 translocations occurred per year in the United States, Canada, New Zealand and Australia. The majority were conducted in the United States. Birds were the most frequently translocated, followed by threatened and endangered species, then non-game species. Of the 261 translocations in the United States reported wild species were most frequently translocated, and the greatest number occurred in the Southeast.
Programs in action today: Western Shield
Western Shield, of Australia, is a nature conservation program which plays an important role in protecting Australia’s native animal population. More importantly, Western Shield also has programs specializing in translocation of endangered and threatened animals. Founded in 1996, it's the most successful wildlife conservation program in Australia and in 2006, it still remains among the largest in the world. The program has already had significant success: three native mammals in Australia – the woylie, quenda and tammar wallaby – have been removed from the threatened species list, many populations of native animals have recovered or been re-established in their former ranges, and the restoration of ecological processes has begun. From 1996 to 2000, Western Shield has taken part of 60 translocations, mostly introductions, comprised of 17 species all over the country on private and interstate lands.
Reasons for failures
Often, when conducting translocation programs, differences in specific habitat types between the source and release sites are not evaluated as long as the release site contains suitable habitat for the species. Translocations could be especially damaging to endangered species citing the failed attempt of Bufo hemiophys baxteri in Wyoming and B. boreas in the Southern Rocky Mountains. For species that have declined over large areas and long periods of time translocations are of little use. Maintaining a large and widely dispersed population of amphibians and other species is the most important aspect of maintaining regional diversity and translocation should only be attempted when a suitable unoccupied habitat exists.
South China Sea Islands,Spratly Islands,Paracel Islands,Pratas Islands,Macclesfield Bank,Scarborough Shoal
The South China Sea Islands (or Nanhai Islands, simplified: 南海诸岛, traditional: 南海諸島, pinyin: Nánhǎi Zhūdǎo) consist of over 250 around 1-km² islands, atolls, cays, shoals, reefs, and sandbars in the South China Sea, most of which have no indigenous people, many of which are naturally under water at high tide, some of which are permanently submerged. The features are grouped into three archipelagos (listed by area size), Macclesfield Bank and Scarborough Shoal:
* The Spratly Islands, disputed between the People's Republic of China, the Republic of China, and Vietnam, with Malaysia and the Philippines claiming part of the archipelago
* The Paracel Islands, disputed between the People's Republic of China, the Republic of China, and Vietnam
* The Pratas Islands, disputed between the People's Republic of China and the Republic of China
* The Macclesfield Bank, disputed between the People's Republic of China, the Philippines, and the Republic of China
* The Scarborough Shoal, disputed between the People's Republic of China, the Philippines, and the Republic of China
There are minerals, natural gas, and oil deposits on the islands and their nearby seafloor. Because of the economic, military, and transportational importance, the control, especially of the Spratlys, has been in dispute by China and several Southeast Asian countries such as Vietnam from the mid-20th century onwards. True occupation and control are shared between the claimants.
History
The countries with the most extensive participation on the South China Sea Islands are China and Vietnam.
The South China Sea Islands were collectively named the Tough Heads of the Surging Sea (漲海崎頭 Zhànghǎi Qítóu) and Coral Cays (珊瑚洲 Shanhu Zhou) since their discovery by the Chinese in the Qin Dynasty. But seafaring did not occur until the next dynasty, the Han Dynasty. After the Song Dynasty, the Islands had been called The Thousand-Mile Long Sands (千里長沙) and Myriad-Mile Stony Embankment (萬里石塘).
There are houses dated back to the Tang or Song Dynasty on Ganquan Island (甘泉島), which nowadays is under dispute with Vietnam. In 1045, during the reign of Emperor Renzong of Song China, imperial troops (王師) were sent to the Paracel Islands. The fishermen of Hainan composed various "Notebooks on Paths and Timing" (更路簿) that recorded over 200 routes, the time needed for sailing among the different isles, and the names of over 100 islands commonly used by the fishermen.
Some of the voyages of Zheng He passed by the Islands, though they probably did not dock on them. There is an atoll in the Spratly Islands named after Zheng He though.
Vietnamese fishermen and merchants also have been exploring the South Sea Islands, with a well-known presence, due to the historically unofficial capacity and shorter records. Vietnamese official documents cite Vietnamese ancient historical records of control and exploitation of the island, and dispute Chinese claims and records.
In the 19th century, as a part of the occupation of Indochina, France claimed control of the Spratlys until the 1930s, exchanging a few with the British. During World War II, the Islands were annexed by Japan.
The People's Republic of China founded in 1949 claimed the islands as part of the province of Canton (Guangdong), and later of the Hainan special administrative region.
* The Spratly Islands, disputed between the People's Republic of China, the Republic of China, and Vietnam, with Malaysia and the Philippines claiming part of the archipelago
* The Paracel Islands, disputed between the People's Republic of China, the Republic of China, and Vietnam
* The Pratas Islands, disputed between the People's Republic of China and the Republic of China
* The Macclesfield Bank, disputed between the People's Republic of China, the Philippines, and the Republic of China
* The Scarborough Shoal, disputed between the People's Republic of China, the Philippines, and the Republic of China
There are minerals, natural gas, and oil deposits on the islands and their nearby seafloor. Because of the economic, military, and transportational importance, the control, especially of the Spratlys, has been in dispute by China and several Southeast Asian countries such as Vietnam from the mid-20th century onwards. True occupation and control are shared between the claimants.
History
The countries with the most extensive participation on the South China Sea Islands are China and Vietnam.
The South China Sea Islands were collectively named the Tough Heads of the Surging Sea (漲海崎頭 Zhànghǎi Qítóu) and Coral Cays (珊瑚洲 Shanhu Zhou) since their discovery by the Chinese in the Qin Dynasty. But seafaring did not occur until the next dynasty, the Han Dynasty. After the Song Dynasty, the Islands had been called The Thousand-Mile Long Sands (千里長沙) and Myriad-Mile Stony Embankment (萬里石塘).
There are houses dated back to the Tang or Song Dynasty on Ganquan Island (甘泉島), which nowadays is under dispute with Vietnam. In 1045, during the reign of Emperor Renzong of Song China, imperial troops (王師) were sent to the Paracel Islands. The fishermen of Hainan composed various "Notebooks on Paths and Timing" (更路簿) that recorded over 200 routes, the time needed for sailing among the different isles, and the names of over 100 islands commonly used by the fishermen.
Some of the voyages of Zheng He passed by the Islands, though they probably did not dock on them. There is an atoll in the Spratly Islands named after Zheng He though.
Vietnamese fishermen and merchants also have been exploring the South Sea Islands, with a well-known presence, due to the historically unofficial capacity and shorter records. Vietnamese official documents cite Vietnamese ancient historical records of control and exploitation of the island, and dispute Chinese claims and records.
In the 19th century, as a part of the occupation of Indochina, France claimed control of the Spratlys until the 1930s, exchanging a few with the British. During World War II, the Islands were annexed by Japan.
The People's Republic of China founded in 1949 claimed the islands as part of the province of Canton (Guangdong), and later of the Hainan special administrative region.
Source-sink dynamics,metapopulation,Source-sink dynamics and Conservation,ideal free distribution
Source-sink dynamics is a theoretical model used by ecologists to describe how variation in habitat quality may affect the population growth or decline of organisms.
Since quality is likely to vary among patches of habitat, it is important to consider how a low quality patch might affect a population. In this model, organisms occupy two patches of habitat. One patch, the source, is high quality habitat that on average allows the population to increase. The second patch, the sink, is very low quality habitat that, on its own, would not be able to support a population. However, if the excess of individuals produced in the source frequently moves to the sink, the sink population can persist indefinitely. Organisms are generally assumed to be able to distinguish between high and low quality habitat, and to prefer high quality habitat. However, ecological trap theory describes the reasons why organisms may actually prefer sink patches over source patches. Finally, the source-sink model implies that some habitat patches may be more important to the long-term survival of the population, and considering the presence of source-sink dynamics will help inform conservation decisions.
Theory development
Although the seeds of a source-sink model had been planted earlier , Pulliam is often recognized as the first to present a fully-developed source-sink model. He defined source and sink patches in terms of their demographic parameters, or BIDE rates (birth, immigration, death, and emigration rates). In the source patch, birth rates were greater than death rates, causing the population to grow. The excess individuals were expected to leave the patch, so that emigration rates were greater than immigration rates. In other words, sources were a net exporter of individuals. In contrast, in a sink patch, death rates were greater than birth rates, resulting in a population decline toward extinction unless enough individuals emigrated from the source patch. Immigration rates were expected to be greater than emigration rates, so that sinks were a net importer of individuals. As a result, there would be a net flow of individuals from the source to the sink.
Pulliam’s work was followed by many others who developed and tested the source-sink model. Watkinson and Sutherland presented a phenomenon in which high immigration rates could cause a patch to appear to be a sink by raising the patch’s population above its carrying capacity (the number of individuals it can support). However, in the absence of immigration, the patches are able to support a smaller population. Since true sinks cannot support any population, the authors called these patches “pseudo-sinks.” Definitively distinguishing between true sinks and pseudo-sinks requires cutting off immigration to the patch in question and determining whether the patch is still able to maintain a population. Thomas et al. were able to do just that, taking advantage of an unseasonable frost that killed off the host plants for a source population of Edith’s checkerspot butterfly (Euphydryas editha). Without the host plants, the supply of immigrants to other nearby patches was cut off. Although these patches had appeared to be sinks, they did not become extinct without the constant supply of immigrants. They were capable of sustaining a smaller population, suggesting that they were in fact pseudo-sinks.
Watkinson and Sutherland's caution about identifying pseudo-sinks was followed by Dias, who argued that differentiating between sources and sinks themselves may be difficult. She asserted that a long-term study of the demographic parameters of the populations in each patch is necessary. Otherwise, temporary variations in those parameters, perhaps due to climate fluctuations or natural disasters, may result in a misclassification of the patches. For example, Johnson described periodic flooding of a river in Costa Rica which completely inundated patches of the host plant for a rolled-leaf beetle (Cephaloleia fenestrata). During the floods, these patches became sinks, but at other times they were no different from other patches. If researchers had not considered what happened during the floods, they would not have understood the full complexity of the system.
Dias also argued that an inversion between source and sink habitat is possible so that the sinks may actually become the sources. Because reproduction in source patches is much higher than in sink patches, natural selection is generally expected to favor adaptations to the source habitat. However, if the proportion of source to sink habitat changes so that sink habitat becomes much more available, organisms may begin to adapt to it instead. Once adapted, the sink may become a source habitat. This is believed to have occurred for the Blue Tit (Parus caeruleus) 7500 years ago as forest composition on Corsica changed, but few modern examples are known. Boughton described a source—pseudo-sink inversion in butterfly populations of E. editha. Following the frost, the butterflies had difficulty recolonizing the former source patches. Boughton found that the host plants in the former sources senesced much earlier than in the former pseudo-sink patches. As a result, immigrants regularly arrived too late to successfully reproduce. He found that the former pseudo-sinks had become sources, and the former sources had become true sinks.
One of the most recent additions to the source-sink literature is by Tittler et al., who examined Wood Thrush (Hylocichla mustelina) survey data for evidence of source and sink populations on a large scale. The authors reasoned that emigrants from sources would likely be the juveniles produced in one year dispersing to reproduce in sinks in the next year, producing a one-year time lag between population changes in the source and in the sink. Using data from the Breeding Bird Survey, an annual survey of North American birds, they looked for relationships between survey sites showing such a one-year time lag. They found several pairs of sites showing significant relationships 60-80 km apart. Several appeared to be sources to more than one sink, and several sinks appeared to receive individuals from more than one source. In addition, some sites appeared to be a sink to one site and a source to another. The authors concluded that source-sink dynamics may occur on continental scales.
One of the more confusing issues involves identifying sources and sinks in the field. Runge et al. point out that in general researchers need to estimate per capita reproduction, probability of survival, and probability of emigration to differentiate source and sink habitats. If emigration is ignored, then individuals that emigrate may be treated as mortalities, thus causing sources to be classified as sinks. This issue is important if the source-sink concept is viewed in terms of habitat quality (as it is in Table 1) because classifying high-quality habitat as low-quality may lead to mistakes in ecological management. Runge et al. showed how to integrate the theory of source-sink dynamics with population projection matrices and ecological statistics in order to differentiate sources and sinks.
Habitat patches are represented in terms of their (1) inherent abilities to maintain a population (in the absence of immigration), (2) their attractiveness to organisms that are actively dispersing and choosing habitat patches, and (3) whether they are net exporters or importers of dispersing individuals. Note that in all of these systems, source patches are capable of supporting stable or growing populations and are net exporters of individuals. The major difference between them is that in the ecological trap model, the source patch is avoided (or at least not preferred to the low quality trap patch). All of the low quality patches (whether sinks, pseudo-sinks, or traps) are net importers of dispersing individuals, and in the absence of dispersal, would show a population decline. However, pseudo-sinks would not decline to extinction as they are capable of supporting a smaller population. The other major difference between these low quality patch types is in their attractiveness; sink populations are avoided while trap patches are preferred (or at least not avoided).
Modes of Dispersal
Why would individuals ever leave high quality source habitat for a low quality sink habitat? This question is central to source-sink theory. Ultimately, it depends on the organisms and the way they move and distribute themselves between habitat patches. For example, plants disperse passively, relying on other agents such as wind or water currents to move seeds to another patch. Passive dispersal can result in source-sink dynamics whenever the seeds land in a patch that cannot support the plant’s growth or reproduction. Winds may continually deposit seeds there, maintaining a population even though the plants themselves do not successfully reproduce.
In contrast, many organisms that disperse actively should have no reason to remain in a sink patch, provided the organisms are able to recognize it as a poor quality patch (see discussion of ecological traps ). The reasoning behind this argument is that organisms are often expected to behave according to the “ideal free distribution,” which describes a population in which individuals distribute themselves evenly among habitat patches according to how many individuals the patch can support. When there are patches of varying quality available, the ideal free distribution predicts a pattern of “balanced dispersal”. In this model, when the preferred habitat patch becomes crowded enough that the average fitness (survival rate or reproductive success) of the individuals in the patch drops below the average fitness in a second, lower quality patch, individuals are expected to move to the second patch. However, as soon as the second patch becomes sufficiently crowded, individuals are expected to move back to the first patch. Eventually, the patches should become balanced so that the average fitness of the individuals in each patch and the rates of dispersal between the two patches are even. In this balanced dispersal model, the probability of leaving a patch is inversely proportional to the carrying capacity of the patch. In this case, individuals should not remain in sink habitat for very long, where the carrying capacity is zero and the probability of leaving is therefore very high.
An alternative to the ideal free distribution and balanced dispersal models is when fitness can vary among potential breeding sites within habitat patches and individuals must select the best available site. This alternative has been called the “ideal preemptive distribution,” because a breeding site can be preempted if it has already been occupied. For example, the dominant, older individuals in a population may occupy all of the best territories in the source so that the next best territory available may be in the sink. As the subordinate, younger individuals age, they may be able to take over territories in the source, but new subordinate juveniles from the source will have to move to the sink. Pulliam argued that such a pattern of dispersal can maintain a large sink population indefinitely. Furthermore, if good breeding sites in the source are rare and poor breeding sites in the sink are common, it is even possible that the majority of the population resides in the sink.
Importance in Ecology
The source-sink model of population dynamics has made contributions to many areas in ecology. For example, a species’ niche was originally described as the environmental factors required by a species to carry out its life history, and a species was expected to be found only in areas that met these niche requirements. This concept of a niche was later termed the “fundamental niche,” and described as all of the places a species could successfully occupy. In contrast, the “realized niche,” was described as all of the places a species actually did occupy, and was expected to be less than the extent of the fundamental niche as a result of competition with other species. However, the source-sink model demonstrated that the majority of a population could occupy a sink which, by definition, did not meet the niche requirements of the species, and was therefore outside the fundamental niche. In this case, the realized niche was actually larger than the fundamental niche, and ideas about how to define a species’ niche had to change.
Source-sink dynamics has also been incorporated into studies of metapopulations, a group of populations residing in patches of habitat. Though some patches may go extinct, the regional persistence of the metapopulation depends on the ability of patches to be re-colonized. As long as there are source patches present for successful reproduction, sink patches may allow the total number of individuals in the metapopulation to grow beyond what the source could support, providing a reserve of individuals available for re-colonization. Source-sink dynamics also has implications for studies of the coexistence of species within habitat patches. Because a patch that is a source for one species may be a sink for another, coexistence may actually depend on immigration from a second patch rather than the interactions between the two species. Similarly, source-sink dynamics may influence the regional coexistence and demographics of species within a metacommunity, a group of communities connected by the dispersal of potentially interacting species. Finally, the source-sink model has greatly influenced ecological trap theory, a model in which organisms prefer sink habitat over source habitat.
Source-sink dynamics and Conservation
Land managers and conservationists have become increasingly interested in preserving and restoring high quality habitat, particularly where rare, threatened, or endangered species are concerned. As a result, it is important to understand how to identify or create high quality habitat, and how populations respond to habitat loss or change. Because a large proportion of a species’ population could exist in sink habitat, conservation efforts may misinterpret the species’ habitat requirements. Similarly, without considering the presence of a trap, conservationists might mistakenly preserve trap habitat under the assumption that an organism’s preferred habitat was also good quality habitat. Simultaneously, source habitat may be ignored or even destroyed if only a small proportion of the population resides there. Degradation or destruction of the source habitat will, in turn, impact the sink or trap populations, potentially over large distances. Finally, efforts to restore degraded habitat may unintentionally create an ecological trap by giving a site the appearance of quality habitat, but which has not yet developed all of the functional elements necessary for an organism’s survival and reproduction. For an already threatened species, such mistakes might result in a rapid population decline toward extinction.
In considering where to place reserves, protecting source habitat is often assumed to be the goal, although if the cause of a sink is human activity, simply designating an area as a reserve has the potential to convert current sink patches to source patches (e.g. no-take zones. Either way, determining which areas are sources or sinks for any one species may be very difficult, and an area that is a source for one species may be unimportant to others. Finally, areas that are sources or sinks currently may not be in the future as habitats are continually altered by human activity or climate change. Few areas can be expected to be universal sources, or universal sinks. While the presence of source, sink, or trap patches must be considered for short-term population survival, especially for very small populations, long-term survival may depend on the creation of networks of reserves that incorporate a variety of habitats and allow populations to interact.
Since quality is likely to vary among patches of habitat, it is important to consider how a low quality patch might affect a population. In this model, organisms occupy two patches of habitat. One patch, the source, is high quality habitat that on average allows the population to increase. The second patch, the sink, is very low quality habitat that, on its own, would not be able to support a population. However, if the excess of individuals produced in the source frequently moves to the sink, the sink population can persist indefinitely. Organisms are generally assumed to be able to distinguish between high and low quality habitat, and to prefer high quality habitat. However, ecological trap theory describes the reasons why organisms may actually prefer sink patches over source patches. Finally, the source-sink model implies that some habitat patches may be more important to the long-term survival of the population, and considering the presence of source-sink dynamics will help inform conservation decisions.
Theory development
Although the seeds of a source-sink model had been planted earlier , Pulliam is often recognized as the first to present a fully-developed source-sink model. He defined source and sink patches in terms of their demographic parameters, or BIDE rates (birth, immigration, death, and emigration rates). In the source patch, birth rates were greater than death rates, causing the population to grow. The excess individuals were expected to leave the patch, so that emigration rates were greater than immigration rates. In other words, sources were a net exporter of individuals. In contrast, in a sink patch, death rates were greater than birth rates, resulting in a population decline toward extinction unless enough individuals emigrated from the source patch. Immigration rates were expected to be greater than emigration rates, so that sinks were a net importer of individuals. As a result, there would be a net flow of individuals from the source to the sink.
Pulliam’s work was followed by many others who developed and tested the source-sink model. Watkinson and Sutherland presented a phenomenon in which high immigration rates could cause a patch to appear to be a sink by raising the patch’s population above its carrying capacity (the number of individuals it can support). However, in the absence of immigration, the patches are able to support a smaller population. Since true sinks cannot support any population, the authors called these patches “pseudo-sinks.” Definitively distinguishing between true sinks and pseudo-sinks requires cutting off immigration to the patch in question and determining whether the patch is still able to maintain a population. Thomas et al. were able to do just that, taking advantage of an unseasonable frost that killed off the host plants for a source population of Edith’s checkerspot butterfly (Euphydryas editha). Without the host plants, the supply of immigrants to other nearby patches was cut off. Although these patches had appeared to be sinks, they did not become extinct without the constant supply of immigrants. They were capable of sustaining a smaller population, suggesting that they were in fact pseudo-sinks.
Watkinson and Sutherland's caution about identifying pseudo-sinks was followed by Dias, who argued that differentiating between sources and sinks themselves may be difficult. She asserted that a long-term study of the demographic parameters of the populations in each patch is necessary. Otherwise, temporary variations in those parameters, perhaps due to climate fluctuations or natural disasters, may result in a misclassification of the patches. For example, Johnson described periodic flooding of a river in Costa Rica which completely inundated patches of the host plant for a rolled-leaf beetle (Cephaloleia fenestrata). During the floods, these patches became sinks, but at other times they were no different from other patches. If researchers had not considered what happened during the floods, they would not have understood the full complexity of the system.
Dias also argued that an inversion between source and sink habitat is possible so that the sinks may actually become the sources. Because reproduction in source patches is much higher than in sink patches, natural selection is generally expected to favor adaptations to the source habitat. However, if the proportion of source to sink habitat changes so that sink habitat becomes much more available, organisms may begin to adapt to it instead. Once adapted, the sink may become a source habitat. This is believed to have occurred for the Blue Tit (Parus caeruleus) 7500 years ago as forest composition on Corsica changed, but few modern examples are known. Boughton described a source—pseudo-sink inversion in butterfly populations of E. editha. Following the frost, the butterflies had difficulty recolonizing the former source patches. Boughton found that the host plants in the former sources senesced much earlier than in the former pseudo-sink patches. As a result, immigrants regularly arrived too late to successfully reproduce. He found that the former pseudo-sinks had become sources, and the former sources had become true sinks.
One of the most recent additions to the source-sink literature is by Tittler et al., who examined Wood Thrush (Hylocichla mustelina) survey data for evidence of source and sink populations on a large scale. The authors reasoned that emigrants from sources would likely be the juveniles produced in one year dispersing to reproduce in sinks in the next year, producing a one-year time lag between population changes in the source and in the sink. Using data from the Breeding Bird Survey, an annual survey of North American birds, they looked for relationships between survey sites showing such a one-year time lag. They found several pairs of sites showing significant relationships 60-80 km apart. Several appeared to be sources to more than one sink, and several sinks appeared to receive individuals from more than one source. In addition, some sites appeared to be a sink to one site and a source to another. The authors concluded that source-sink dynamics may occur on continental scales.
One of the more confusing issues involves identifying sources and sinks in the field. Runge et al. point out that in general researchers need to estimate per capita reproduction, probability of survival, and probability of emigration to differentiate source and sink habitats. If emigration is ignored, then individuals that emigrate may be treated as mortalities, thus causing sources to be classified as sinks. This issue is important if the source-sink concept is viewed in terms of habitat quality (as it is in Table 1) because classifying high-quality habitat as low-quality may lead to mistakes in ecological management. Runge et al. showed how to integrate the theory of source-sink dynamics with population projection matrices and ecological statistics in order to differentiate sources and sinks.
Habitat patches are represented in terms of their (1) inherent abilities to maintain a population (in the absence of immigration), (2) their attractiveness to organisms that are actively dispersing and choosing habitat patches, and (3) whether they are net exporters or importers of dispersing individuals. Note that in all of these systems, source patches are capable of supporting stable or growing populations and are net exporters of individuals. The major difference between them is that in the ecological trap model, the source patch is avoided (or at least not preferred to the low quality trap patch). All of the low quality patches (whether sinks, pseudo-sinks, or traps) are net importers of dispersing individuals, and in the absence of dispersal, would show a population decline. However, pseudo-sinks would not decline to extinction as they are capable of supporting a smaller population. The other major difference between these low quality patch types is in their attractiveness; sink populations are avoided while trap patches are preferred (or at least not avoided).
Modes of Dispersal
Why would individuals ever leave high quality source habitat for a low quality sink habitat? This question is central to source-sink theory. Ultimately, it depends on the organisms and the way they move and distribute themselves between habitat patches. For example, plants disperse passively, relying on other agents such as wind or water currents to move seeds to another patch. Passive dispersal can result in source-sink dynamics whenever the seeds land in a patch that cannot support the plant’s growth or reproduction. Winds may continually deposit seeds there, maintaining a population even though the plants themselves do not successfully reproduce.
In contrast, many organisms that disperse actively should have no reason to remain in a sink patch, provided the organisms are able to recognize it as a poor quality patch (see discussion of ecological traps ). The reasoning behind this argument is that organisms are often expected to behave according to the “ideal free distribution,” which describes a population in which individuals distribute themselves evenly among habitat patches according to how many individuals the patch can support. When there are patches of varying quality available, the ideal free distribution predicts a pattern of “balanced dispersal”. In this model, when the preferred habitat patch becomes crowded enough that the average fitness (survival rate or reproductive success) of the individuals in the patch drops below the average fitness in a second, lower quality patch, individuals are expected to move to the second patch. However, as soon as the second patch becomes sufficiently crowded, individuals are expected to move back to the first patch. Eventually, the patches should become balanced so that the average fitness of the individuals in each patch and the rates of dispersal between the two patches are even. In this balanced dispersal model, the probability of leaving a patch is inversely proportional to the carrying capacity of the patch. In this case, individuals should not remain in sink habitat for very long, where the carrying capacity is zero and the probability of leaving is therefore very high.
An alternative to the ideal free distribution and balanced dispersal models is when fitness can vary among potential breeding sites within habitat patches and individuals must select the best available site. This alternative has been called the “ideal preemptive distribution,” because a breeding site can be preempted if it has already been occupied. For example, the dominant, older individuals in a population may occupy all of the best territories in the source so that the next best territory available may be in the sink. As the subordinate, younger individuals age, they may be able to take over territories in the source, but new subordinate juveniles from the source will have to move to the sink. Pulliam argued that such a pattern of dispersal can maintain a large sink population indefinitely. Furthermore, if good breeding sites in the source are rare and poor breeding sites in the sink are common, it is even possible that the majority of the population resides in the sink.
Importance in Ecology
The source-sink model of population dynamics has made contributions to many areas in ecology. For example, a species’ niche was originally described as the environmental factors required by a species to carry out its life history, and a species was expected to be found only in areas that met these niche requirements. This concept of a niche was later termed the “fundamental niche,” and described as all of the places a species could successfully occupy. In contrast, the “realized niche,” was described as all of the places a species actually did occupy, and was expected to be less than the extent of the fundamental niche as a result of competition with other species. However, the source-sink model demonstrated that the majority of a population could occupy a sink which, by definition, did not meet the niche requirements of the species, and was therefore outside the fundamental niche. In this case, the realized niche was actually larger than the fundamental niche, and ideas about how to define a species’ niche had to change.
Source-sink dynamics has also been incorporated into studies of metapopulations, a group of populations residing in patches of habitat. Though some patches may go extinct, the regional persistence of the metapopulation depends on the ability of patches to be re-colonized. As long as there are source patches present for successful reproduction, sink patches may allow the total number of individuals in the metapopulation to grow beyond what the source could support, providing a reserve of individuals available for re-colonization. Source-sink dynamics also has implications for studies of the coexistence of species within habitat patches. Because a patch that is a source for one species may be a sink for another, coexistence may actually depend on immigration from a second patch rather than the interactions between the two species. Similarly, source-sink dynamics may influence the regional coexistence and demographics of species within a metacommunity, a group of communities connected by the dispersal of potentially interacting species. Finally, the source-sink model has greatly influenced ecological trap theory, a model in which organisms prefer sink habitat over source habitat.
Source-sink dynamics and Conservation
Land managers and conservationists have become increasingly interested in preserving and restoring high quality habitat, particularly where rare, threatened, or endangered species are concerned. As a result, it is important to understand how to identify or create high quality habitat, and how populations respond to habitat loss or change. Because a large proportion of a species’ population could exist in sink habitat, conservation efforts may misinterpret the species’ habitat requirements. Similarly, without considering the presence of a trap, conservationists might mistakenly preserve trap habitat under the assumption that an organism’s preferred habitat was also good quality habitat. Simultaneously, source habitat may be ignored or even destroyed if only a small proportion of the population resides there. Degradation or destruction of the source habitat will, in turn, impact the sink or trap populations, potentially over large distances. Finally, efforts to restore degraded habitat may unintentionally create an ecological trap by giving a site the appearance of quality habitat, but which has not yet developed all of the functional elements necessary for an organism’s survival and reproduction. For an already threatened species, such mistakes might result in a rapid population decline toward extinction.
In considering where to place reserves, protecting source habitat is often assumed to be the goal, although if the cause of a sink is human activity, simply designating an area as a reserve has the potential to convert current sink patches to source patches (e.g. no-take zones. Either way, determining which areas are sources or sinks for any one species may be very difficult, and an area that is a source for one species may be unimportant to others. Finally, areas that are sources or sinks currently may not be in the future as habitats are continually altered by human activity or climate change. Few areas can be expected to be universal sources, or universal sinks. While the presence of source, sink, or trap patches must be considered for short-term population survival, especially for very small populations, long-term survival may depend on the creation of networks of reserves that incorporate a variety of habitats and allow populations to interact.
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