Pollution of land has to be curbed. If land is polluted through (say) improper waste disposal, it will not only hamper the growth of plant and crops but may also lead to other problems. Ground water may become polluted when the pollutants percolate down the layers of soil along with runoff water. Also, the pollutants may enter into crops and from there into food chain.
Similarly, air pollutants emitted into air finally settle down and most of these fall on land to pollute soil. For example, you might have seen that land near a thermal power station or a large factory equipments become polluted by pollutants discharged from the chimneys into air if it does not have adequate pollution control equipments.
From the air, the pollutants, especially TEL (Tetra ethyl lead) as a group are dangerous air pollution agents settle down with rains. Most of them find way to soil. If a chemical has long life and cannot easily be decomposed, it can create severe problems.
Heavy metals are also generally toxic and they are not decomposed. So, they enter the food chain and create problems for organisms at higher tropic levels which may include man. It caused by TEL lead. It can damaged brain, cause cancer and lead to still birth etc. lead is also used very commonly as an additive in petrol. When petrol is used in our cars, scooters, etc. when petrol is used in our cars, scooters, etc, lead is discharged into air. From there, it settles on soil and enters the food chain.
The pollution of soil may be caused by different agents such as:
b) Heavy metals
c) Inorganic salts of metals and other elements
d) Radioactive substances
Among these, radioactive substances are of limited importance as these are not used at many places and there is a strong control on manufacture, sale and use of radioactive materials. Accidentally, however, these substances may sometimes get into the environment.
A large number of these chemicals are toxic too. When these chemicals mix with soil, they create problems. Hence, it is essential to curb land pollution. This is possible if adequate pollution control measures are adopted at every level. For example, solid wasters and liquid waters are properly treated before these are disposed. Sludge treatment takes care of the pollutants present in these wasters.
So, an all-round control on pollution is essential to curb land pollution. For this the Government has passed several legislations such as Water Prevention and Control of Pollution Act, 1974, Air Prevention and Control Pollution Act 1981.
Later, these Acts were amended to make them more effective. Ministry of Environment & Forests, Government of India. Central Pollution Control Board, and State Pollution Control Boards, have been given powers to control pollution of all types including pollution of land. But it is essential that all of us should make effort to keep our land free from pollution.