Soil Pollution: Sources, Effects and Methods to Control
Soil Pollution: It is the contamination of soil or land with solid waste, acid rain, excess of fertilizers, insecticides and herbicides.
Sources of Soil Pollution
- Solid wastes come from homes, cattle sheds, agricultural fields, industries and many other places and get accumulated in the form of heaps. Solid wastes include cow dung, human excreta, fruit and vegetable peels, ash, waste paper, worn out clothes, leather and rubber articles, plastic objects, glass pieces and metal objects.
- Acid rain is basically a mixture of sulphur dioxide and nitrogen oxides present in polluted air. It makes the soil acidic.
- Use of excess fertilizers makes the soil either acidic or alkaline and pollutes it.
- Insecticides and herbicides used to control pests are poisonous chemicals which when sprayed to standing crops get mixed with the soil and pollutes it.
- Plastic bags made from low-density polyethylene is another source of land pollution. bags. Plastic is non-biodegradable and burning of plastic in garbage dumps release highly toxic and poisonous gases.
Harmful Effects of Soil Pollution
- Solid wastes like garbage becomes a breeding ground for mosquitoes which spread diseases. Moreover, decomposition of such waste materials causes foul smell and release harmful gases which damage the environment.
- Acid rain reduces the fertility of soil leading to reduction in crop yields.
- Excessive use of fertilisers also reduces the fertility of soil and crop yield.
- Chemical discharged from industries often enter the surface or ground water and contaminates it.
- Insecticides and herbicides used in agriculture are generally persistent in nature, which may enter our food chain and damage our health.
- Particles in the sewage destroy the microorganisms necessary for soil.
- The discarded plastic bags block drains and sewage systems. Leftover food, vegetable waste etc. on which cows and dogs feed may die due to the choking by plastic bags. Poisonous gases released during burning of plastic wastes further pollutes air and may cause lung diseases in humans.
Methods to Control Soil Pollution
- Recycling: It is the method of recovery and processing of biodegradable wastes or materials after they have been used which enables them to be reused.
- Composting: In this method, domestic wastes like fruit and vegetable waste, left over food, leaves of potted plants, etc can be converted into compost and used as manure. This is an eco-friendly measure which also provides manure for kitchen garden without harming the environment.
- Production of Biogas: Cow dung and domestic waste can be used for the production of biogas instead of dumping which contaminates the soil.
- Incineration: It is a process through which a substance is burned at high temperature to form ash. It is used to destroy household waste, chemical waste and biological waste. All the organic matter present in waste is removed through this process.
- Bags made of degradable materials like paper and cloth should be used in place of plastic bags.
- Sewage should be treated properly before dumping and biomedical waste should be separately collected and incinerated.