Soil pollution can be defined as the contamination of soil bringing adverse affects on the organisms in it. It can also be defined as the addition of unwanted substances in odd proportion. Soil pollution is also called as land pollution. Here pollutants remain in direct contact with the soil for a long period of time, than that of water and air. Hence its problems are different from that of water and air pollution.
The widespread industrialization and increasing consumption have changed the composition and complexion of earth strata. It can be said that soil is being heavily polluted day by day by the toxic materials coming out of industries and domestic circles. The most common chemicals involved are petroleum hydrocarbons, polynuclear aromatic hydrocarbons (such as naphthalene and benzo(a)pyrene ) solvents, pesticides, lead, and other heavy metals.
Sources of Soil Pollution
The major sources of soil or land pollution are
- Industrial waste
- Urban waste
- Chemical and metallic pollutants
- Biological agents
- Radioactive pollutants
- Agricultural practices
Disposal of industrial waste is one of the major reasons for soil pollution. Industrial waste mainly consists of organic; inorganic and non-biodegradable materials. These pollutants change the physiochemical and biological aspects of the soil such as change in texture, mineral, bacterial and fungal colonies in the soil.
Because of the consumerism, our life style and food habits have been changing and are dumping us towards the point of danger. It includes both commercial and domestic waste, which is commonly referred to as refuse. This refuse along with solid waste contribute to soil pollution.
Chemical and metallic pollutant
Various industries such as textile, dyes, soap and synthetic, detergents, drugs and metal industries dump their hazardous waste in soil and water, directly creating harmful impact on living organism.
Harmful organism such as bacteria, fungi, algae, protozoan and microorganisms such as nematodes, earthworms, millipedes, snail etc. alter the physiochemical and biological atmosphere of the soil leading to soil pollution.
Various radioactive substances are introduced to the environment by different sources such as nuclear reactors, scientific laboratories, explosions, hospitals etc. They penetrate into the soil and accumulate there for many years creating soil pollution.
Advance agro-technology, huge quantities of fertilizers, pesticides, herbicides and weedicides are used to increase the fertility of the soil but their excessive use disrupts the soil’s physiochemical and biological property.
The other sources of soil pollution includes:
- Municipal garbage and chemical composition
- Mining practices and overcrowded landfills
- Food processing waste
- Sugarcane trash in the field
- Deforestation and soil erosion
Effects of soil pollution
- Hazardous chemical entered into the food chain from soil, causes disruption of biochemical process, leads to skin cancer and human respiratory system.
- Soil becomes infertile because of water logging and salinity and loss of agricultural lands.
- Toxic chemicals affect plant growth and animal life.
- Change in the climate pattern and biodiversity.
- Cause for the land pollution.
Control Measures for Soil Pollution
- The waste from various industries should be properly treated before dumping into the soil and water.
- Use of bio-fertilizers should be promoted instead of chemical fertilizers.
- Use of toxic and non-biodegradable materials should be discouraged.
- Education programmes regarding soil pollution and prevention measures should be promoted.
- There should be strict enforcement of environment protection law.
- Recycling and reuse of solid waste generated from various sources should be done.
- Maximum tree plantation should be initiated to minimize soil pollution.