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Sunday, September 21, 2008

Logging

Logging is the process in which trees are cut down for forest management and timber. Logging is controversial due to its potential environmental and aesthetic impacts.

Use of the term logging in forestry


In forestry the term logging is sometimes used in a narrow sense concerning the logistics of moving wood from the stump to somewhere outside the forest, usually a mill. In common usage however the term may be used to indicate a range of forestry or silviculture activities. For example the practice of the removal of a valuable trees from the forest has been called selective logging sometimes confused with selection cut.Illegal logging refers to what in forestry might be called timber theft. An example of illegal logging is cedar theft, which is most common in the American Pacific Northwest. Timber theft in all forms is quite rare in the United States. In common usage what is sometimes called clearcut logging is not is necessarily considered a type of logging but a harvest or silviculture method and is simply called clearcutting or block cutting. In the forest products industry logging companies may be referred as logging contractors.

Logging usually refers to above-ground forestry logging. Submerged forests exist on land that has been flooded to create artificial dams and reservoirs, and trees have started to be felled there too.

Logging methods- Tree-length logging-Full-tree logging-Cut-to-length logging

The above operations can be carried out by different methods, of which the following three are considered industrial methods:

Tree-length logging


Trees are felled and then delimbed and topped at the stump. The log is then transported to the landing, where it is bucked and loaded on a truck. This leaves the slash (and the nutrients it contains) in the cut area where it must be further treated if wildland fires are of concern.

Full-tree logging


Trees are felled and transported to the roadside with top and limbs intact. The trees are then delimbed, topped, and bucked at the landing. This method requires that slash be treated at the landing. In areas with access to cogeneration facilities, the slash can be chipped and used for the production of clean electricity or heat. Full-tree harvesting also refers to utilization of the entire tree including branches and tops. This technique removes both nutrients and soil cover from the site and so can be harmful to the long term health of the area if no further action is taken, however, depending on the species, many of the limbs are often broken off in handling so the end result may not be as different from tree-length logging as it might seem.

Cut-to-length logging


Big trees are felled, delimbed, bucked, and sorted (pulpwood, sawlog, etc.) at the stump area, leaving limbs and tops in the forest. Harvesters fell the tree, delimb and buck it, and place the resulting logs in bunks to be brought to the landing by the forwarder. This method is usable for smaller timber on ground flat enough that forwarders can operate, but does not work well on steep slopes.

Logging and safety

Logging is a dangerous occupation. In the United States, it has consistently been one of the most hazardous industries, having a fatality rate over 21 times higher than the rate for all workers in the US. Loggers work with heavy, moving weights and the use of tools such as chainsaws and heavy equipment on uneven and sometimes unstable terrain. Loggers also deal with severe environmental conditions such as inclement weather and severe heat or cold. An injured logger is often far from professional emergency treatment.

Traditionally, the cry of "Timber!" developed as a warning alert fellow workers in an area that a tree is being felled, so they should be alert to avoid being struck. The term "widowmaker" for timber that is neither standing nor fallen to the ground demonstrates another emphasis on situational awareness as a safety principle.

The risks experienced in logging operations can be somewhat reduced, where conditions permit, by the use of mechanical tree harvesters and forwarders.

Logging and the environment- Mitigation- Impact of logging operations- Impact of tree harvesting

The many impacts of logging on the environment can be divided into two broad categories, the timber harvest itself, that is, the removal of trees from the forest, and secondly the impact caused by logging operations such as falling or dragging trees and operation of machinery in the forest.

Impact of tree harvesting

Removal of trees alters species composition, the structure of the forest, and can cause nutrient depletion. This may provide opportunities for some species while creating a loss of opportunity for others. Trees providing midday shade to streams which may alter the stream's temperature either by preventing the sun from shining on the water by day, or by preventing the water from radiating the heat back at night.

In altering the balance of animal and plant species, logging, if not limited to sufficiently small areas, alters the ecological system of the forest. The effect on ecosystems and on biodiversity is the small-scale effect of unrestricted logging.

The large-scale effect of the removal of trees is obviously the impact on the level of carbon in the atmosphere, with its consequences on global climate. Besides the carbon release due to possible burning associated with logging, or possibly with wood processing, the removal of trees prevents carbon from being captured by the trees from the atmosphere. Deforestation, frequently associated with logging, has been assessed to be in fact responsible for 17 percent of annual global carbon a level higher than the one from emissions due to transportation.

Impact of logging operations

Modern ground based logging operations require the use of heavy machinery in the forest. In some areas roads must be built which often causes habitat fragmentation and increased edge effect. The use of heavy machinery in a forest can cause soil compaction. Harvesting on steep slopes can lead to soil erosion, landslides, and water turbidity. Logging on saturated soils can cause ruts and change drainage patterns. Harvest activity near wetlands or vernal pools can degrade the habitat. Forest machines use oils which, if not handled carefully, can cause pollution. Roadbuilding for access to timber in frontier forests often opens up areas previously not accessible, which facilitates further development such as farming.

Mitigation

These problems can be mitigated by using low-impact logging and best management practices, which set standards for reducing erosion from roads. Damage to streams and lakes can be reduced by not harvesting riparian strips. Mitigating the effect of logging can require the full restriction on logging on ecologically important lands, such as forests with a high level of biodiversity. Technological advances in logging equipment can reduce ruts and soil disturbance. Processors and forwarders with caterpillar tracks or other designs to lower ground pressure help to reduce machine impact.

Friday, September 19, 2008

Intensive farming-capital, fertilizers, labour

Intensive farming or intensive agriculture is an agricultural production system characterized by the high inputs of capital, fertilizers, labour, or labour-saving technologies such as pesticides relative to land area. This is in contrast to the concept of Extensive Agriculture which involves a low input of materials and labour with the crop yield depending largely on the naturally available soil fertility, water supply or other land qualities.

Modern day forms of intensive crop based agriculture involve the use of mechanical ploughing, chemical fertilizers, herbicides, fungicides, insecticides, plant growth regulators and/or pesticides. It is associated with the increasing use of agricultural mechanization, which have enabled a substantial increase in production.

Intensive animal farming practices can involve very large numbers of animals raised on limited land which require large amounts of food, water and medical inputs (required to keep the animals healthy in cramped conditions). Very large or confined indoor intensive livestock operations (particularly descriptive of common US farming practices) are often referred to as Factory farming and are criticised by opponents for the low level of animal welfare standards and associated pollution and health issues.

Advantages


Intensive agriculture has a number of benefits

* Significantly increased yield per available space than extensive farming.
* Often leads to cheaper priced products because of better general production rate for the cost of raw materials.
* Not much space for the animal(s) to move therefore less energy used up; so less food supplied to the cattle, which leads to cheaper products.
* Many people feel it's necessary to use intensive farming for better profits and economy

Disadvantages


Intensive farming alters the environment in many ways.

* Limits the natural habitat of some wild creatures and can lead to soil erosion.
* Use of fertilizers can alter the biology of rivers and lakes environmentalists attribute the hypoxic zone in the Gulf of Mexico as being encouraged by nitrogen fertilization of the algae bloom.
* Pesticides can kill useful insects as well as those that destroy crops.
* Generally not sustainable.
* Often results in an inferior product.
* Use of chemicals on fields creates run-off, excess runs off into rivers and lakes causing pollution.
* Animal welfare is significantly decreased compared to organic, animals are kept in tight living conditions, over-fed and only have a small life span before being slaughtered.

Individual industrial agriculture farm-Herbicide resistance- Nutrient audits-Water use efficiency-Crop sequencing- Integrated farming systems

Major challenges and issues faced by individual industrial agriculture farms include:

* integrated farming systems
* crop sequencing
* water use efficiency
* nutrient audits
* herbicide resistance
* financial instruments (such as futures and options)
* collect and understand own farm information;
* knowing your products
* knowing your markets
* knowing your customers
* satisfying customer needs
* securing an acceptable profit margin
* cost of servicing debt;
* ability to earn and access off-farm income;
* management of machinery and stewardship investments.

Integrated farming systems



An integrated farming system is a progressive biologically integrated sustainable agriculture system such as Integrated Multi-Trophic Aquaculture or Zero waste agriculture whose implementation requires exacting knowledge of the interactions of numerous species and whose benefits include sustainability and increased profitability.

Elements of this integration can include:

* intentionally introducing flowering plants into agricultural ecosystems to increase pollen-and nectar-resources required by natural enemies of insect pests
* using crop rotation and cover crops to suppress nematodes in potatoes

Crop sequencing


Crop rotation or crop sequencing is the practice of growing a series of dissimilar types of crops in the same space in sequential seasons for various benefits such as to avoid the build up of pathogens and pests that often occurs when one species is continuously cropped. Crop rotation also seeks to balance the fertility demands of various crops to avoid excessive depletion of soil nutrients. A traditional component of crop rotation is the replenishment of nitrogen through the use of green manure in sequence with cereals and other crops. It is one component of polyculture. Crop rotation can also improve soil structure and fertility by alternating deep-rooted and shallow-rooted plants.

Water use efficiency


Crop irrigation accounts for 70% of the world's fresh water use. The agricultural sector of most countries is important both economically and politically, and water subsidies are common. Conservation advocates have urged removal of all subsidies to force farmers to grow more water-efficient crops and adopt less wasteful irrigation techniques.

For crop irrigation and plant irrigation, optimal water efficiency means minimizing losses due to evaporation or runoff. An evaporation pan can be used to determine how much water is required to irrigate the land. Flood irrigation, the oldest and most common type, is often very uneven in distribution, as parts of a field may receive excess water in order to deliver sufficient quantities to other parts. Overhead irrigation, using center-pivot or lateral-moving sprinklers, gives a much more equal and controlled distribution pattern, but in extremely dry conditions much of the water may evaporate before it reaches the ground. Drip irrigation is the most expensive and least-used type, but offers the best results in delivering water to plant roots with minimal losses.

As changing irrigation systems can be a costly undertaking, conservation efforts often concentrate on maximizing the efficiency of the existing system. This may include chiseling compacted soils, creating furrow dikes to prevent runoff, and using soil moisture and rainfall sensors to optimize irrigation schedules.

Water catchment management measures include recharge pits, which capture rainwater and runoff and use it to recharge ground water supplies. This helps in the formation of ground water wells etc. and eventually reduces soil erosion caused due to running water.

Nutrient audits


Better nutrient audits allow farmers to spend less money on nutrients and to create less pollution since less nutrient is added to the soil and thus there is less to run off and pollute. Methodologies for assessing soil nutrient balances have been studied and used for farms and entire countries for decades. But at present "there is no standard methodology for calculating nutrient budgets and there are no accepted 'benchmarks' figures against which to assess farm nutrient use efficiency. [A standard methodology] for calculating nutrient budgets on farms [is hoped to help reduce] diffuse water and air pollution from agriculture [through] best management practices in the use of fertilisers and organic manures, as part of the continued development of economically and environmentally sustainable farming systems."

Herbicide resistance


In agriculture large scale and systematic weeding is usually required, often performed by machines such as cultivators or liquid herbicide sprayers. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often based on plant hormones. Weed control through herbicide is made more difficult when the weeds become resistant to the herbicide. Solutions include:

* using cover crops (especially those with allelopathic properties) that out-compete weeds and/or inhibit their regeneration.
* using a different herbicide
* using a different crop (e.g. genetically altered to be herbicide resistant; which ironically can create herbicide resistant weeds through horizontal gene transfer)
* using a different variety (e.g. locally-adapted variety that resists, tolerates, or even out-competes weeds)
* ploughing
* ground cover such as mulch or plastic
* manual removal

Modern intensive farming types- Managed intensive grazing-Intensive livestock farming-Intensive aquaculture- Sustainable intensive farming

Modern intensive farming refers to the industrialized production of animals (livestock, poultry and fish) and crops. The methods deployed are designed to produce the highest output at the lowest cost; usually using economies of scale, modern machinery, modern medicine, and global trade for financing, purchases and sales. The practice is widespread in developed nations, and most of the meat, dairy, eggs, and crops available in supermarkets are produced in this manner.

Sustainable intensive farming

Biointensive agriculture focuses on maximizing efficiency: yield per unit area, yield per energy input, yield per water input, etc. Agroforestry combines agriculture and orchard/forestry technologies to create more integrated, diverse, productive, profitable, healthy and sustainable land-use systems. Intercropping can also increase total yields per unit of area or reduce inputs to achieve the same, and thus represents (potentially sustainable) agricultural intensification. Unfortunately, yields of any specific crop often diminish and the change can present new challenges to farmers relying on modern farming equipment which is best suited to monoculture.

Intensive aquaculture

Aquaculture is the cultivation of the natural produce of water (fish, shellfish, algae, seaweed and other aquatic organisms). Intensive Aquaculture can often involve tanks or other highly controlled systems which are designed to boost production for the available volume or area of water resource.

Intensive livestock farming


The modern examples of intensive farming are broadly referred to as Concentrated Animal Feeding Operations (CAFOs) or often termed Factory farming. These include:

* Intensive pig farming or Intensive piggery farming
* Large scale chicken farms
* Cattle feed lots

Managed intensive grazing

This sustainable intensive livestock management system is increasingly used to optimize production within a sustainability framework and is generally not considered Factory farming.

Pre modern intensive farming

Pre modern intensive farming techniques and structures include terracing, rice paddies, and various forms of aquaculture.

Oysters

"Oysters were likely the first sea animal to be transported from one area to another and cultivated as food. The ancient world, while knowing little about the reproduction of oysters, knew much about the conditions necessary for their growth. Pliny the Elder, a noted Roman naturalist of the first century, has left an account of artificial oyster beds established in Lake Lucrinus near Naples by a Sergius Orata about 95 B.C. Orata's methods consisted of preparing the grounds by removing other forms of marine life, planting seed oysters, cultivating the oysters by keeping them separated in order to grow to a well-formed, mature size, and finally harvesting them when they were ready for market. Modern oyster farming, based on the knowledge of oyster biology, basically follows the Roman procedure.Fisheries and Oceans Canada] article American Oyster

Terrace

In agriculture, a terrace is a leveled section of a hilly cultivated area, designed as a method of soil conservation to slow or prevent the rapid surface runoff of irrigation water. Often such land is formed into multiple terraces, giving a stepped appearance. The human landscapes of rice cultivation in terraces that follow the natural contours of the escarpments like contour ploughing is a classic feature of the island of Bali and the Banaue Rice Terraces in Benguet, Philippines. In Peru, the Inca made use of otherwise unusable slopes by drystone walling to create terraces.

Rice paddy

A paddy field is a flooded parcel of arable land used for growing rice and other semiaquatic crops. Paddy fields are a typical feature of rice-growing countries of east and southeast Asia including Malaysia, China, Sri Lanka, Myanmar, Thailand, Korea, Japan, Vietnam, Taiwan, Indonesia, India, and the Philippines. They are also found in other rice-growing regions such as Piedmont (Italy), the Camargue (France) and the Artibonite Valley (Haiti). They can occur naturally along rivers or marshes, or can be constructed, even on hillsides, often with much labour and materials. They require large quantities of water for irrigation, which can be quite complex for a highly developed system of paddy fields. Flooding provides water essential to the growth of the crop. It also gives an environment favourable to the strain of rice being grown, and is hostile to many species of weeds. As the only draft animal species which is adapted for life in wetlands, the water buffalo is in widespread use in Asian rice paddies. There are significant adverse environmental impacts from rice paddy cultivation due to the generation of large quantities of methane gas. World methane production due to rice paddies has been estimated in the range of 50 to 100 million tonnes per annum; this level of greenhouse gas generation is a large component of the global warming threat and derives simply from an expanding human population.

Rice-farming and the use of paddies in Korea is ancient. Korean paddy-farming can provide cultural background on the use of paddies in East Asia. A pit-house at the Daecheon-ni site yielded carbonized rice grains and radiocarbon dates indicating that rice cultivation may have begun as early as the Middle Jeulmun Pottery Period (c. 3500-2000 B.C.) in the Korean Peninsula (Crawford and Lee 2003). The earliest rice cultivation in the Korean Peninsula may have used dry-fields instead of paddies.

The earliest Mumun features were usually located in low-lying narrow gulleys that were naturally swampy and fed by the local stream system. Some Mumun paddies in flat areas were made of a series of squares and rectangles separated by bunds approximately 10 cm in height, while terraced paddies consisted of long irregularly shapes that followed natural contours of the land at various levels (Bale 2001; Kwak 2001).

Mumun Period rice farmers used all of the elements that are present in today's paddies such terracing, bunds, canals, and small reservoirs. We can grasp some paddy-farming techniques of the Middle Mumun (c. 850-550 B.C.) from the well-preserved wooden tools excavated from archaeological rice paddies at the Majeon-ni Site. However, iron tools for paddy-farming were not introduced until sometime after 200 B.C. The spatial scale of individual paddies, and thus entire paddy-fields, increased with the regular use of iron tools in the Three Kingdoms of Korea Period (c. A.D. 300/400-668).

Sunday, September 7, 2008

Pollution

Industrial solid waste are also sorted out as biodegradable and non degradable wastes bio degradable wastes are generated by cotton mills food processing units and paper mills and textile factories
Non biodegradable wastes are generated by thermal power plants which produce fly ash integrated iron and steel plants which produce blast furnace slag and stell melting slag industries manufacturing aluminum zinc and copper produce gypsum hazardous wastes such as immflammables composite explosives or highly reactive substances are produced by industries dealing in metals chemicals dues etc
The disposal of non degradable industrial wastes if not done by a proper and suitable method may cause serious thereat to the environment new innovation have led to different used of waste material nowadays fly ash and slag from the steel industry are utilized by the cement industry large quantities of toxic wastes are usually destroyed by controlled incineration whereas small quantities are burnt along with factory garbage in open bins moreover solid wastes if not managed effectively affect the components of the environment


STARTEGIES T O CONTROL ENVIRONMENTAL POLLUTION
After studying air water soil and industrial waste pollution in this unit by now you must have started feeling the need of controlling environmental pollution
Waste management
Solid waste is not he only waste which u see your house hold garbage box besides house hold discard there are medical agricultural ,industrial and mining wastes the improper disposal of wastes is one of the major causes of environmental degradation therefore the management of wastes is of utmost importance
COLLECTION AND DISPOSAL
Domestic wastes are collected in small bins which are then transferred to community bins by private or municipal workers .from this small bins these are collected and carried to the disposal box

GREEN CHEMISTRY

It is well known fact that self sufficiency in good has been achieved in India since late 20 century by using fertilizes and pesticides and exploring improved methods of farming good quality seeds irrigation etc but over exploitation of soil and excessive used of fertilizers and pesticides have resulted in the deterioration of soil water and air
The solution of this problem does not lie in the stopping the process of development that has been set in but to discover methods which would help in the reduction of deterioration of the environment green chemistry is a way of thinking and is about utilizing the existing knowledge and principles of chemistry and other science to reduce the adverse impact on environment. that a would bring about minimum pollution or deterioration to the environment .The bye products generated during a process if not used gainfully add to the environmental pollution such process not only environmental unfriendly but also cost – ineffective the waste generation and its disposal both are economically un sound utilization of existing knowledge base for reducing the chemical hazards along with the developmental activities is the foundation of green chemistry
Posted by josh at 8:52 PM 0 comments
pottution
ENVIRONMENTAL POLLUTION
Environmental pollution is the effect of undesirable and changes in our surrounding that have harmful effects on plants animals and human beings a substance which causes pollution is knows as pollutant pollutants can be solids liquids or gaseous substances present in greater concentration than in natural abundance and are produced due to human activates or due to natural happenings



ATMOSPHERIC POLLUTION
The atmosphere that surrounds the earth is not of the same thickness at all heights there are concentric layers of air and regions and each layer has different density
The lowest region of atmosphere in which the human beings along with other organisms live is called the troposphere it extends up to the height of 10 and 50 kilometer troposphere is a turbulent dusty zone containing air much water vapour and clouds. this is the region of strong air movement and cloud formation the stratosphere on the other hand contains dinitrogen dioxygen ozone and little water vapour

TROPOSHERIC POLLUTION
Troposphere pollution occurs due to the presence of undesirable solid or gaseous particles in the air the following are the major gaseous and particulate pollutants present in the troposphere .Gaseous air pollutants there are oxides of sulphur nitrogen and carbon hydrogen sulphide nitrogen ozone and other oxidants
Particulate pollutants these are dust mist fumes smoke etc

Gaseous air pollutants
Oxides of sulphur
Oxides of sulphur containing fossil fuel is burnt in air the most common species sulphur dioxide is a gas that is poisonous to both animals and plants it has been reported that even a low concentration of sulphur dioxide Causes asthma bronchitis .sulphur dioxide causes irritation to the eyes resulting in tears and redness high concentration of son3 leads to stiffness to flower buds which eventually fall off from plants unanalyzed oxidation of sulphur dioxide is slow however the presence of particulate matter in polluted air catalyses the oxidation of sulphur dioxide to sulphur trioxide

Oxides of nitrogen
Dinitrogen and dioxygen are the main constituents of air these gases do not react with each other at a normal temperature at high altitudes when lighting strikes they combine to form oxides of nitrogen no is oxidized to nitrate ion Which is washed into soil where it serves as a fertilizer in an automobile engine when fossil fuel is burnt dinitrogen and dioxygen combine to yield significant quantities of nitric oxide and nitrogen dioxide

Oxides of carbon
Carbon monoxide
Carbon monoxide is one of the most serious air pollutants it is a colourless gas highly poisonous to living beings because of its ability to block the delivery of oxygen to the organs and tissues it is produced as a result of incomplete combustion of coal firewood petrol the number of vehicles has been increasing over the rears all over the world many vehicles are poorly maintained and several have inadequate pollution control equipments resulting in the release of greater amount of carbon monoxide
Carbon dioxide
Carbon dioxide is released into the atmosphere by respiration burning of fossil fuels

for energy and by decomposition of lime stone carbon dioxide gas is confined to troposphere only
Global warming and green house effect
About 75%pf the solar energy reaching the earth is absorbed by the earth surface which increase its temperature the rest of the hear radiates back to the atmosphere some of the hear is trapped by gases such as carbon dioxide methane ozone chlorofluorocarbon compounds and water vapor in the atmosphere thus they add to the heating of the atmosphere this cause global warming

Stratospheric pollution
Formation and breakdown of ozone The upper stratosphere consists of considerable amount o ozone which protects us from the harmful ultraviolet radiations coming from the sum. These radiations cause skin cancer in humans there fore it is important to maintain the ozone shield .Ozone in the stratosphere is a product of uv radiations acting on dioxygen molecules the uv radiations split apart molecular oxygen into free oxygen atoms these oxygen atoms combine with the molecular oxygen to form ozone is thermodynamically unstable and decomposes to molecular oxygen thus a dynamic equilibrium exists between the production and decomposition of ozone molecules in recent years there have been reports of the depletion of this protective ozone layer because of the presence of certain chemicals in the stratosphere .
The ozone hole
In atmospheric scientists working in Antarctica reported about depletion of ozone layer commonly knows as ozone hole over the south pole nitrogen dioxide and methane react with chlorine monoxide and chlorine atoms forming chlorine sinks preventing much ozone depletion where as in winter special type of clouds called polar stratospheric clouds are formed over Antarctica these polar stratospheric clouds provide surface on which chlorine nitrate formed gets hydrolyzed to form hypochlorous acid. It also reacts with HCl produced as per reaction to give molecular chlorine.
When sunlight returns to the Antarctica in the spring, the sun’s warmth breaks up the clouds and HOCl and Cl2 are photolysis by sunlight. The chlorine radicals thus formed, initiate the chain reaction for ozone depletion.
Effects of Depletion of the Ozone Layer
With the depletion of ozone layer, more UV radiation filters into troposphere. UV radiations lead to ageing of skin, cataract, sunburn , skin cancer, killing of many phytoplankton’s, damage to fish productivity etc.

WATER POLLUTION

Water is essential for life without water there would be no life we usually as granted for it purity but we must ensure the quality of water. Pollution of water originates from human activities. Easily identified sources of water pollution is called point source. E.g., municipal and industrial discharge pipes where pollutants enter the water-source. on point sources of pollution are those where a source of pollution cannot be easily identified, e.g., agricultural run off, acid rain, storm-water drainage etc.

Causes of Water Pollution
1) Pathogens: The most serious water pollutants are the disease causing agents called pathogens. Pathogens include bacteria and other organisms that enter water from domestic sewage and animal excreta. Human excreta contain bacteria such as Escherichia coli and Streptococcus faecalis which cause gastro intestinal disease
2) Organic wastes : the other major water pollutant is organic matter such as leaves grass trash etc they pollute water as consequence of run off .excessive phytoplankton’s growth with in water is also a cause of water pollution these wastes are also biodegradable
3) Chemical pollutants : as we know that water is an excellent solvent water soluble inorganic chemicals that include heavy metals such as cadmium mercury nickel
Etc constituent an important class of pollutants as all these chemicals are dangerous to humans as our body can’t excrete them over the time it crosses the tolerance limit these metals then can damage kidneys central nervous system liver etc

ENVIRONMENTAL POLLUTION
Environmental pollution is the effect of undesirable and changes in our surrounding that have harmful effects on plants animals and human beings a substance which causes pollution is knows as pollutant pollutants can be solids liquids or gaseous substances present in greater concentration than in natural abundance and are produced due to human activates or due to natural happenings

Tuesday, September 2, 2008

The challenge of integrating environmental requirements into the common agricultural policy

agriculture and environment

Since ratification of the Maastricht Treaty, there has been a legal obligation on the Union to take account of environmental protection requirements when drawing up and implementing Community policies, an obligation which was reinforced by the entry into force of the Treaty of Amsterdam on 1 May 1999.

In the case of the common agricultural policy (CAP), which accounts for almost 50% of the Community budget, the need to take account of environmental concerns is not only a legal requirement but is vital for the very existence of the policy.

Since the process of European integration began, the CAP has contributed to meeting the changing demands of society. In addition to ensuring a fair standard of living for those involved in farming, this has involved, inter alia, increasing production in order to guarantee food supplies to the population and encouraging the modernisation of agriculture. Among the benefits that this has brought to society at large are the transfer of productivity gains to the rest of the economy, the consolidation of internal demand and the release of manpower required in other sectors. Numerous specialists have written of "the crisis of traditional agriculture" and "the silent revolution" in our countryside. The common agricultural policy, just like "modern agriculture", today stands at the crossroads. Building and consolidating a European model of agriculture means developing a farming sector which is at the same time market-oriented, environment-friendly and multifunctional, i.e. which responds to all the demands which society places upon it.

Identifying effects

A number of effects identified elsewhere in this publication deserve to be looked at in more detail. They can be divided into two major groups: past developments and recent evolution, in particular since the 1992 reform.

Past developments

* As regards use of the land and countryside, European farmers directly manage and maintain 44% of European land as utilised agricultural area (UAA), and when the remaining land they own or rent and work is taken into account, they manage more than half of Europe's land surface.

* The area devoted to farming has decreased noticeably over the last two decades. Certain areas of the EU have been abandoned or marginalised, either because access was difficult or because they were no longer suitable for farming as a result, in particular, of the fall in farm prices (a marked economic trend linked to the transfer of productivity gains already mentioned), the pressure of urbanisation and tourism or as a result of general economic developments, a particular consequence of which has been rural depopulation.

* Shaped by geography, history, culture and economic developments, the EU's regions show astonishing diversity. With its wealth of agricultural activities, diversity of regional agricultural systems and different levels and modes of economic development, rural society is multifaceted.

* From the soil to the countryside and from land occupation to land use, everything that affects the territory of Europe forms part of our common heritage. The technical and cultural development of human civilisation has seen human settlements develop from a dependency on food supply sources to almost total freedom from any constraints on location. The countryside is an essential aspect of European agriculture. The countryside and its development include inter alia biodiversity, combating erosion and preventing forest fires. The very concept of the countryside is a complex one.

* The existence in Europe over several decades of an agricultural policy based on intervention to ensure high prices and unlimited and guaranteed outlets helped harness the productive potential generated by technological progress for agricultural intensification and specialisation. This had a negative impact on, amongst other things, the environment, the countryside and the quality of certain products offered to the consumer. To deny this would be just as wrong as to place the blame for it exclusively on the common agricultural policy or on agricultural policy in general.

* On the whole, there was a steady increase in the production of arable crops in Europe. Community aid for cereals, protein crops and oilseeds, together with a fall in the number of grazing animals, has led to an increase in the production of cash crops at the expense of permanent grassland and other forage areas (pasture and areas devoted to secondary cereals). Simplified crop rotation, the increased importance of annual crops and the priority given to financial criteria made possible by improved farming techniques are the principal changes observed in arable farming over the last 25 years.

* Traditional mixed and livestock holdings lost ground to specialised holdings, with the consolidation of large production regions.

* The production-oriented logic of these decades, which were viewed as "miraculous", often led farmers to give priority to financial profitability to the detriment of sustainable farming. Among other effects on crop rotation, one can point to the reduction in the number of traditional crops grown (to the benefit of common wheat and grain maize); the increase in the share of annual crops, including fodder; the appearance in certain regions of almost single-crop farming; the spread of land improvements (increases in the size of holdings, drainage, irrigation, consolidation).

* The intensification of livestock farming has brought larger holdings, greater specialisation, geographical concentration and a reduction in the number of farmers.

* We can only touch on the relationship between water management and agricultural activities, inter alia owing to the lack of data. We have, for example, no data on drainage and the drying-out of wetlands, which means that we must concentrate on irrigation. Since statistics have been available (1961 for the 15 Member States), there has been a strong tendency for the area of irrigable land to increase, even though this seems less marked over recent years. No clear general link (positive or negative) can be established, however, between this and the environment or sustainable development.

* With regard to water quality, the problems of nitrate, phosphate and pesticide pollution have been studied. The role of intensive agriculture is not in doubt, even if other sectors of the economy may also be the cause of a large proportion of pollution problems.

Recent evolution, in particular since the 1992 reform

* The 1992 reform of the CAP introduced support measures for agri-environment measures at European level to encourage more environment-friendly production methods. These measures affect one European farmer in 7 and cover 20% of the agricultural area, well beyond the objective of 15% set by the Fifth Environmental Action Programme 1.

Participation by the Member States is unequal ; while some (Finland, Austria, Sweden, Germany) are above average, others (Belgium, Denmark, Greece, Spain and the Netherlands) fall below. Among the reasons put forward to explain this are the innovative nature of the measures, their complexity, the problems caused for certain administrations, political priorities, the balance in certain Member States between central and regional governments, budgetary difficulties in certain Member States (or regions) in providing the necessary part-financing, the cultural reticence of some farmers and the economic benefits of continuing to practise intensive agriculture.

Among the innovations contained in the measure are the importance given to subsidiarity (the Member States draw up their own programmes), the fact that the participation of producers in the programmes is entirely voluntary and the multiannual nature of the programmes.

* Since the 1992 reform, organic farming has been growing in importance, today accounting for 1% of holdings and 2% of the utilised agricultural area, which means that organic holdings are of above average size. Here too, the situation varies enormously from one region to another. In general, livestock farming (despite delays in adopting Community legislation) followed by fruit and vegetable growing seem to attract organic farmers more than arable farming.

* Natura 2000 today covers approximately 9% of European territory. Contrary to a commonly held view, it is not a question of creating complete nature reserves or of freezing all human activity. Quite the contrary, the areas concerned are "semi-natural" areas, created and maintained by human activity, which might even disappear if farming ceased. Experience so far shows that it is not only desirable but also perfectly possible to develop farming practices that maintain, and even improve, the nature value of habitats and species.

* Agriculture is at the same time a cause, solution and victim of climatic change. It is certainly the principal source of methane and nitrous oxide emissions but is overall responsible for only 8% of greenhouse gas emissions. Furthermore, the increase in woodland in Europe helps absorb carbon dioxide. Between 1993 and 1997, more than half a million hectares were reafforested in the European Union.

The example of methane is a perfect illustration of the complexity of the problem. To reduce emissions while maintaining production levels would initially mean reducing the dairy cattle population, i.e. intensifying production. Taking the argument to the extreme, the use of bovine somatotrophin might even be considered. Such intensification would aggravate the environmental problems of excess nitrogen, the abandonment of vulnerable areas, public and animal health, and product quality, leaving aside animal welfare considerations.

* The 1992 reform marks a point of no return. Farmers changed the way they operated and rational farming increased. There was less use of fertilisers and pesticides, and techniques changed. The use of inputs, which already marked time during the 1980s, initially fell following the fall in prices and the disquiet and uncertainty felt by the agricultural world following the reform, and then rose when world and Community market prices increased. It is still too early to gauge the impact of the changes in prices (rising in the middle of the 1990s and falling at the end of the decade) on the use of inputs.

* The importance of technological change cannot be ignored. It has an influence on the volumes of inputs used, their composition, their methods of application and their environmental impact. Thus an increase in production potential can lead to a rise in the volume of inputs used per hectare but a fall per unit of product obtained and, given the cost of labour, mechanisation can, all things being equal, bring an increase in the amounts applied.

* Another measure with a potentially positive impact on the environment, if the system is correctly managed, is the obligatory or voluntary set-aside of land. Initially left to apply set-aside as they pleased, farmers were gradually led to incorporate it into their crop-rotation systems. In the case of fixed 60-month or long-term voluntary set-aside, the areas released could be used for genuine environmental measures including cover for game.

* The production of non-food crops has soared, especially on land participating in the various set-aside programmes. Approximately 15% of set-aside areas are utilised for such crops.

* Biomass remains the principal renewable energy source. Wood from forests is the oldest and most widespread biofuel, but the agricultural sector provides an increasing share of the biomass used for energy production. Indeed, woody crops are gradually becoming established on what was originally agricultural land, in particular under mechanisms introduced as part of the 1992 reform, such as support for the afforestation of agricultural land and set-aside.

The rural contribution to other renewable forms of energy involves above all hydro-electricity, from small dams, wind energy, which now has the wind in its sails, and solar energy.

* Of the non-food crops grown on set-aside land, oilseeds for the production of biodiesel cover the greatest area. Biofuels face competition from fossil fuels and their development depends on suitable tax instruments applied as part of energy and/or environmental policy.

* The fall in cereal prices has made intensive livestock farming more attractive in cereal areas, far from the regions near ports, where problems of pollution often arise. These regions have seen a reduction in the logistical advantage of privileged access to animal feed imported from third countries they used to enjoy because of a system of tariff protection weighted against cereals.

* Other elements may have had a negative environmental impact, at least in certain regions of the Union, in particular, the extension to silage maize of the aid for grain cereals and the system of premiums adopted for beef and veal.

* One can therefore conclude that, from the point of view of the environment, the 1992 reform of the CAP represented a step in the right direction, even if a number of provisions had the opposite effect to that intended.

Conclusions confirmed

The analysis set out in this publication confirms what the Commission stated in its Communication to the Council and the European Parliament: "Directions towards sustainable agriculture 2":

* More than three-quarters of the EU's territory are agricultural land or woodland 3. While the environment and land use vary greatly from the Mediterranean to the sub-arctic regions, there is clearly a significant link between agriculture and the conservation of the environment throughout the EU.

* As commercial activities, agriculture and forestry are aimed principally at production, which both relies on the availability of natural resources and, in exploiting these resources, places environmental pressure on them. Technological developments and commercial pressures to maximise returns and minimise costs have given rise to a marked intensification of agriculture in the last 40 years. The role of the common agricultural policy in the intensification of agriculture must also be recognised.

* A high level of price support encouraged intensive agriculture and increased use of fertilisers and pesticides. This has resulted in water and soil pollution which has destroyed certain important ecosystems and required expensive treatments to the cost of the consumer and the taxpayer.

* Among the other environmental developments accelerated by the CAP price policy are the effects of the changes to the countryside brought about by the intensification of agriculture. The destruction of hedgerows, stone walls and ditches and the draining of wetlands have contributed to the loss of natural habitats for many birds, plants and other species. Intensification in certain areas has led to an excessive use of water in relation to the resources available and accelerated soil erosion.

* During the last 15 years, there has been a growing awareness that the variety of landscapes and the related biodiversity shaped by agriculture over the centuries (a unique semi-natural environment with a rich variety of species dependent on the continuation of farming) could be harmed by the intensification of agriculture. Intensification not only raises problems for the countryside and biodiversity but also threatens the soil, water and the air.

* The abandonment of farmland, mainly for economic reasons, also creates pressure on the countryside and biodiversity. In Europe the abandonment of farming would damage biodiversity and would not normally lead to the restoration of the original landscape. The problems created by both the intensification and the abandonment of farming therefore raise questions about the relationship between agriculture and the environment and the future basis for the European model of sustainable agriculture.

The statistical challenge

This publication shows that, although a large quantity of statistical data is available, there are a number of gaps in statistical systems.

A mass of information is available...

We are better placed to exploit a large amount of statistical data held mainly by Eurostat, supplemented by national or local case studies.

But this source has not been fully exploited. For example, there is still room for improvement, making better use of the results of the structural survey, production statistics and balances and Eurostat's regional database, to take only three of the most obvious examples. Other sources of information, such as the geographical databases managed by the Joint Research Centre and the European Environment Agency or the Farm Accountancy Data Network (FADN) also deserve to be made better use of.

... but there are large gaps


The most recent statistical data on which numerous articles are based is from the 1995 farm structure survey, but these are inadequate for a full assessment in 1999 of structural phenomena such as the impact of the 1992 reform.

Linked to this problem, is that of the frequency of the surveys and the time taken to make the results available. A survey every 10 years does not permit identification of all the small changes taking place in the intervening periods, whose effects can be significant if, for example, market prices change considerably within a period, since the samples selected for the intermediate surveys are only representative of the agricultural sector as it was at the time of the last ten-year survey.

If data is not up to date or is unrepresentative of a dynamic sector, political decision-makers do not have the information required to evaluate the detailed economic impact of their decisions.

The geographical dimension

Since farming deals with living things, the same political measure, the same farming practice, the same approach by a farmer will have environmental consequences which differ completely from one area to another, from one location to another. Thus, for example, the calculation of a driving force indicator for the impact of livestock farming on the territory of a Member State or even of a region (NUTS 2) is mathematically possible but would give relatively little useful information about the real pressure that livestock farming can exert on the environment. The analysis of agricultural data must reflect reality at local level and it is no longer enough to achieve representativity on only a national or regional scale.

The need for analysis at the local level raises the problem of the availability of data at such a level, with the dual problem of the cost of gathering data (which increases) and representativity (which decreases) as the scale is reduced, if the correct level is not chosen.

Furthermore, statistical data are often gathered on the basis of administrative divisions which do not fully correspond to the local level at which environmental impact must be evaluated.

The missing data

The complexity of the links between farming and the environment, the necessary geographical dimension, and the fact that the public demand for environmental information is new explain why large amounts of data either does not exist or is not yet available in harmonised form at European level.

Obtaining new data is hampered by the Member States' and the Commission's budgetary imperatives and by the time elapsing between the need for statistics being felt and their availability in a harmonised form at European level, which is, at best, several years.

Conclusions: the necessary political priorities

All these tasks, however necessary they might be, cannot be undertaken at the same time. To be effective, to be able to respond in time to the requests of the political decision-makers and public opinion, managers of statistical data have to tailor their work to the changing needs of the political decision-makers. The statistical tools could be better adjusted to needs if clear priorities were defined. That is why the question of the use and the usefulness of data and indicators in general, and of environmental indicators in particular, must be a priority, from both the political point of view and for the implementation of statistical systems.

The problem of the use of data

The implementation of European policy is changing, becoming more decentralised, with greater subsidiarity. One of the practical consequences of this development is the increased importance of the prior, intermediate and ex post evaluation of policies.

This involves inter alia:

* defining a baseline scenario against which the impact of policies can be measured,
* identifying the real objectives of those policies and ordering them hierarchically,
* assessing the expected impact of public measures sufficiently early,
* stipulating the criteria for judging the success of policies,
* developing indicators which permit not only an assessment of how a situation is changing but also of the impact of the policies being implemented.

One of the most difficult tasks is to isolate the specific impact of a policy from other factors. This involves distinguishing between the impact of policies adopted by the Community and that of inter alia:

* national, and sometimes regional, transposing legislation,
* other Community, national, regional and local policies,
* general economic developments,
* other sectors of the economy,
* developments on Community and world markets,
* major existing trends such as demography, technical progress or technological innovations,
* specific local factors.

The problem of developing agri-environmental indicators

The above fully applies to environmental assessment, particularly of the CAP, and to the development of suitable agri-environmental indicators.

The definition and development of indicators which make it possible to see more clearly and measure the interaction between the environment and farming would clearly be a step forward, helping to ensure that public opinion and political decision-makers were better informed and more aware.

However, the Commission needs to be much more ambitious. The aim must be not simply to improve monitoring but also to provide political decision-makers, primarily Community decision-makers, in good time, with data which allow them to identify causes and effects and on which they can base policy.

The agricultural sector has important characteristics, already referred to in this publication, which differentiate it from other sectors of the economy:

* the fact that agriculture deals with living things. Production cycles are longer - a year in arable farming, but much longer in, for example, fruit growing and cattle and sheep farming - which accentuates even more the need to gather data in good time in order to ensure its reliability. Furthermore, a large number of things such as production volumes, farming practices, input volumes, water consumption and the diversity of fauna and flora, depend on external factors such as the vagaries of the weather, which make data analysis more difficult, or soil characteristics,
* the close link between farming and locality,
* the importance of public policy, and primarily of the common agricultural policy, in regulating economic activity in the sector,
* the ambivalent relation between farming and the environment,
* the decisive importance of local assessment in correctly evaluating the impact of policy.

These characteristics explain why in its Communication the Commission stressed that:

The development of indicators must be based as far as possible on existing statistics. However, it should not be too dependent on the current availability of data. The work to develop indicators must be intensified, and, at the same time, think tanks must be set up to look at new data requirements. It is also necessary to ensure that appropriate statistical instruments are created.

In its Communication, the Commission indicated that this task was "a priority in the work of the Commission over the coming months and years". The Commission, in close cooperation with the Member States and the European Environment Agency, intends to begin implementing a strategy which is, at the same time, ambitious, thorough and realistic.

This publication is a first result. We have attempted to contribute with facts and figures to the debate on the incorporation of environmental concerns in the CAP. As well as providing preliminary conclusions, it paves the way for the work now beginning on inter alia such important questions as water, the countryside, biodiversity and nutrient balances.

We would not wish to round off these conclusions without thanking those colleagues without whom this work would not have been possible. It has been a genuinely collective effort, from the initial work done by the authors, to the patient way they dealt with the many comments from colleagues who read through their work, to those colleagues' efforts to turn their initial observations into positive contributions, often supported by documentation.

This publication is also an invitation to join the debate and help cast light on these issues. If we have succeeded in combating a number of received ideas, stimulating thought and encouraging new work, all those colleagues and friends who have invested so much in this work will feel themselves well rewarded.