Soil Pollution
Soil Pollution
The soil is a mixture of plants, minerals and dead animals which takes many, many years to form. This process can last thousands of years. Soil is necessary for the majority of plants to grow and is vital for all agricultural produce. Soil is polluted when there is an accumulation of toxic chemical substances, salts and pathogens (microorganisms that cause diseases). These and any other radioactive substances can affect the life of plants and animals. The soil pollution is the form of pollution which is the most difficult to detect and control. The soil is even more difficult to detoxify. It is the land that is used to deposit household or commercial waste on. The mud in the station where waste waters are treated is deposited on land under the shape of water slurry or dry. The slurry contains important quantities of nutritious substances, such as nitrate and phosphor. The waste is decomposed when it comes into contact with soil. The places where waste is deposited are to be carefully watched so that they would not hide infected areas. Many such places that were used for decades to deposit waste were reclaimed and turned into park areas or building sites. The use on a large scale of fertilizers may diminish the capacity of bacteria to decompose organic waste to create the nutritious agents necessary for the plants. Pest-killers cause damage to bacteria and other microorganisms. On the other hand, the soil contains various fertilizers, such as nitrates, which come to the surface while ploughing or during winter. The aluminum found in the soil can get into waters through different chemical reactions. When water is treated to become drinkable, some chemicals remain into it.
It is all very known that the disastrous explosion at the Chernobyl, near Kiev, in 1986, seriously affected our delicately balanced ecosystem. Moreover, radioactive substances were released into the atmosphere, and they eventually entered the soil. The radioactive particles were wind carried over a large stretch of land, including the north part of Scandinavian Peninsula and Wales. All animals contaminated were destroyed.
We can see that the soil can be polluted in various ways: either directly, by discharging wastes onto rural or urban lands; by fertilizers and pesticides thrown on agricultural fields. Indirectly, by contaminated rains, or rains that wash contaminated atmosphere. As a rule, the most contaminated land areas are in the very vicinity or contaminating sources. It is interesting to notice that the taller the chimneys that evacuate contaminated gases are, the lower the level of contamination in the neighboring area. Unfortunately, the contaminated regions will extend their surface. The level of soil contamination depends very much on the rainfalls that characterize the area. These wash in general the air and deposit the polluting agents over the soil. At the same time, rain washes the soil, too and helps them get deeper. Nevertheless, the contamination of deeper layers is possible. More or less, the soil pollution is related to the vegetation grown on it. For a better environmental protection pesticides need to be well fixed to the soil. Actually, some of them are carried by winds, others rain-washed, and the rest of them is decomposed in time, due to oxidation in contact with air or due to the enzymes secreted by bacteria living in the soil.