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Possible environmental solutions

Many different solutions to the problems have been suggested over the years, varying in feasibility and cost, including:

· Improving the quality of irrigation canals

· Installing desalination plants

· Charging farmers to use the water from the rivers

· Using alternative cotton species that require less water[31]

· Promoting non-agricultural economic development in upstream countries[32]

· Using fewer chemicals on the cotton

· Cultivating crops other than cotton

· Installing dams to fill the Aral Sea

· Redirecting water from the Volga, Ob and Irtysh Rivers to restore the Aral Sea to its former size in 20–30 years at a cost of US$30–50 billion[33]

· Pumping sea water into the Aral Sea from the Caspian Sea via a pipeline, and diluting it with fresh water from local catchment areas[34]

In January 1994, Kazakhstan, Uzbekistan, Turkmenistan, Tajikistan, and Kyrgyzstan signed a deal to pledge 1% of their budgets to help the sea recover.

In March 2000, UNESCO presented their "Water-related vision for the Aral Sea basin for the year 2025"[at the second World Water Forum in The Hague. This document was criticized for setting unrealistic goals and for giving insufficient attention to the interests of the area immediately around the former lakesite, implicitly giving up on the Aral Sea and the people living on the Uzbek side of the lake.

By 2006, the World Bank's restoration projects, especially in the North Aral, were giving rise to some unexpected, tentative relief in what had been an extremely pessimistic picture


40.

Pollutant Sources Effects
Ozone. A gas that can be found in two places. Near the ground (the troposphere), it is a major part of smog. The harmful ozone in the lower atmosphere should not be confused with the protective layer of ozone in the upper atmosphere (stratosphere), which screens out harmful ultraviolet rays. Ozone is not created directly, but is formed when nitrogen oxides and volatile organic compounds mix in sunlight. That is why ozone is mostly found in the summer. Nitrogen oxides come from burning gasoline, coal, or other fossil fuels. There are many types of volatile organic compounds, and they come from sources ranging from factories to trees. Ozone near the ground can cause a number of health problems. Ozone can lead to more frequent asthma attacks in people who have asthma and can cause sore throats, coughs, and breathing difficulty. It may even lead to premature death. Ozone can also hurt plants and crops.
Carbon monoxide. A gas that comes from the burning of fossil fuels, mostly in cars. It cannot be seen or smelled. Carbon monoxide is released when engines burn fossil fuels. Emissions are higher when engines are not tuned properly, and when fuel is not completely burned. Cars emit a lot of the carbon monoxide found outdoors. Furnaces and heaters in the home can emit high concentrations of carbon monoxide, too, if they are not properly maintained. Carbon monoxide makes it hard for body parts to get the oxygen they need to run correctly. Exposure to carbon monoxide makes people feel dizzy and tired and gives them headaches. In high concentrations it is fatal. Elderly people with heart disease are hospitalized more often when they are exposed to higher amounts of carbon monoxide.
Nitrogen dioxide. A reddish-brown gas that comes from the burning of fossil fuels. It has a strong smell at high levels. Nitrogen dioxide mostly comes from power plants and cars. Nitrogen dioxide is formed in two ways—when nitrogen in the fuel is burned, or when nitrogen in the air reacts with oxygen at very high temperatures. Nitrogen dioxide can also react in the atmosphere to form ozone, acid rain, and particles. High levels of nitrogen dioxide exposure can give people coughs and can make them feel short of breath. People who are exposed to nitrogen dioxide for a long time have a higher chance of getting respiratory infections. Nitrogen dioxide reacts in the atmosphere to form acid rain, which can harm plants and animals.
Particulate matter. Solid or liquid matter that is suspended in the air. To remain in the air, particles usually must be less than 0.1-mm wide and can be as small as 0.00005 mm. Particulate matter can be divided into two types—coarse particles and fine particles. Coarse particles are formed from sources like road dust, sea spray, and construction. Fine particles are formed when fuel is burned in automobiles and power plants. Particulate matter that is small enough can enter the lungs and cause health problems. Some of these problems include more frequent asthma attacks, respiratory problems, and premature death.
Sulfur dioxide. A corrosive gas that cannot be seen or smelled at low levels but can have a “rotten egg” smell at high levels. Sulfur dioxide mostly comes from the burning of coal or oil in power plants. It also comes from factories that make chemicals, paper, or fuel. Like nitrogen dioxide, sulfur dioxide reacts in the atmosphere to form acid rain and particles. Sulfur dioxide exposure can affect people who have asthma or emphysema by making it more difficult for them to breathe. It can also irritate people's eyes, noses, and throats. Sulfur dioxide can harm trees and crops, damage buildings, and make it harder for people to see long distances.
Lead. A blue-gray metal that is very toxic and is found in a number of forms and locations. Outside, lead comes from cars in areas where unleaded gasoline is not used. Lead can also come from power plants and other industrial sources. Inside, lead paint is an important source of lead, especially in houses where paint is peeling. Lead in old pipes can also be a source of lead in drinking water. High amounts of lead can be dangerous for small children and can lead to lower IQs and kidney problems. For adults, exposure to lead can increase the chance of having heart attacks or strokes.
Toxic air pollutants. A large number of chemicals that are known or suspected to cause cancer. Some important pollutants in this category include arsenic, asbestos, benzene, and dioxin. Each toxic air pollutant comes from a slightly different source, but many are created in chemical plants or are emitted when fossil fuels are burned. Some toxic air pollutants, like asbestos and formaldehyde, can be found in building materials and can lead to indoor air problems. Many toxic air pollutants can also enter the food and water supplies. Toxic air pollutants can cause cancer. Some toxic air pollutants can also cause birth defects. Other effects depend on the pollutant, but can include skin and eye irritation and breathing problems.
Stratospheric ozone depleters. Chemicals that can destroy the ozone in the stratosphere. These chemicals include chlorofluorocarbons (CFCs), halons, and other compounds that include chlorine or bromine. CFCs are used in air conditioners and refrigerators, since they work well as coolants. They can also be found in aerosol cans and fire extinguishers. Other stratospheric ozone depleters are used as solvents in industry. If the ozone in the stratosphere is destroyed, people are exposed to more radiation from the sun (ultraviolet radiation). This can lead to skin cancer and eye problems. Higher ultraviolet radiation can also harm plants and animals.
Greenhouse gases. Gases that stay in the air for a long time and warm up the planet by trapping sunlight. This is called the “greenhouse effect” because the gases act like the glass in a greenhouse. Some of the important greenhouse gases are carbon dioxide, methane, and nitrous oxide. Carbon dioxide is the most important greenhouse gas. It comes from the burning of fossil fuels in cars, power plants, houses, and industry. Methane is released during the processing of fossil fuels, and also comes from natural sources like cows and rice paddies. Nitrous oxide comes from industrial sources and decaying plants. The greenhouse effect can lead to changes in the climate of the planet. Some of these changes might include more temperature extremes, higher sea levels, changes in forest composition, and damage to land near the coast. Human health might be affected by diseases that are related to temperature or by damage to land and water.

 




41. The technological backwardness of industry and agriculture, extensive use of natural resources have resulted in the significant degradation of soils in Kazakhstan. Deserted and salted areas are at the territory of more than 50 thousand square kilometres in the Aral Sea and Balkhash Lake basins. Fertility of soils of the flooded area of the Irtysh River is reduced in connection with the excessive regulation of the runoff and the long-term poly-metal production. Problem of soil degradation is especially sharp in North Kazakhstan, zone of the grain agriculture. For the period of the long-term plugging of virgin lands the content of humus has decreased by 5-20 % and more. 1.2 billion tons or 28.3 % from 4.3 billion tons of the humus stocks of the arable layer (0-25 sm.) are irrevocably lost because of mineralising the organic substance, subtraction with a crop, water and wind erosion. Simultaneously the soil fertility is reduced at the expense of deterioration of its agro-physical characteristics, in basic owing to soil compaction by machines. In grain regions of the north of the country 17.8 million hectares are potentially subject to deflation and 2.6 million hectares suffer from strong wind erosion. According to the last inventory of irrigated lands a half from them requires meliorate improvement or restoration of fertility.

Introduction of the sustainable system of agriculture promotes also to solve the problem of greenhouse gases. Its principal core is the technology of formation of the organic soils, which is based on biological activity of fertile substrates with increase of the humus content, thus there is the mass concentration of CO2 in humus from air and linkage of carbon of the organic rests.

For 35 years soils of the North Kazakhstan have lost 570 million tons of the organic carbon. At mineralizing the organic carbon of the soil humus, in basic, oxidises up to, and the emission of CO2 in air for this period has made no less than 1.5 billion tons. At the first stage of sustainable “organic” agriculture it is necessary to expect the return process of linking of CO2 of air and fastening it in soil organic substance in about the same volume. Simultaneously on the other territory of the country in organic substance of soils not yet less than 1.5 billion tons of CO2 will be linked. These volumes of CO2 require specification after recalculation on soil zones and sub-zones of Kazakhstan.

The transition to sustainable systems of agriculture will be long and difficult. But in conditions of increased soil degradation in Kazakhstan it has no alternative, as in the result such systems give of fertile soil, sound environment, high quality food products and reduction of the greenhouse gas emissions.

Main Causes of Soil Pollution

1. Industrial Activity: Industrial activity has been the biggest contributor to the problem in the last century, especially since the amount of mining and manufacturing has increased. Most industries are dependent on extracting minerals from the Earth. Whether it is iron ore or coal, the by products are contaminated and they are not disposed off in a manner that can be considered safe. As a result, theindustrial waste lingers in the soil surface for a long time and makes it unsuitable for use.

2. Agricultural Activities: Chemical utilization has gone up tremendously since technology provided us with modern pesticides and fertilizers. They are full of chemicals that are not produced in nature and cannot be broken down by it. As a result, they seep into the ground after they mix with water and slowly reduce the fertility of the soil. Other chemicals damage the composition of the soil and make it easier to erode by water and air. Plants absorb many of these pesticides and when they decompose, they cause soil pollution since they become a part of the land.

3. Waste Disposal: Finally, a growing cause for concern is how we dispose of our waste. While industrial waste is sure to cause contamination, there is another way in which we are adding to the pollution. Every human produces a certain amount of personal waste products by way or urine and feces.

While much of it moves into the sewer the system, there is also a large amount that is dumped directly into landfills in the form of diapers. Even the sewer system ends at the landfill, where thebiological waste pollutes the soil and water. This is because our bodies are full of toxins and chemicals which are now seeping into the land and causing pollution of soil.

4. Accidental Oil Spills: Oil leaks can happen during storage and transport of chemicals. This can be seen at most of the fuel stations. The chemicals present in the fuel deteriorates the quality of soil and make them unsuitable for cultivation. These chemicals can enter into the groundwater through soil and make the water undrinkable.

 


Date: 2016-01-03; view: 836


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