Soil pollution is defined as:
“The contamination of soil with undesirable and harmful substance “
Composition of soil:
It contains mineral matter, organic matter, living forms like algae etc., water and air.
The causes for soil pollution are:
- Agricultural pollutants:
- They are toxic chemicals.
- The continuous use of similar pesticides gives rise to pest that are resistant to same type of pesticides making their effect ineffective.
- These high persistent toxins are transferred from lower level to higher tropic levels occur due to which bio magnifications takes place.Therefore, metabolic and physiological disorders. a new series of more biodegradable products called organophosphates and carbamates are introduced in market.But these chemicals cause severe nerve toxins and hence more harmful.These days herbicides such as sodium chlorate, sodium arsenate and many other are toxic to mammals.These chemicals take few months to decompose.Some herbicides cause birth defects.
- Industrial waste:
- Industrial solid waste is also divided out biodegradable and non-biodegradable.
- Biodegradable waste is generated by cotton miles etc., are also generated in thermal plants which produce fly ash, integrated iron and steel plants which produce blast furnace slag and steel melting slag.Industries manufacturing aluminium, zinc and copper produce mud. Fertilizer industries produce gypsum. hazardous waste like inflammables, composite explosives or highly reactive substances are produced by industries dealing in metals,drugs,chemicals, pharmaceutical dyes, pesticides, rubber etc. a new innovation have led to different uses of waste materials.Now a day’s fly-ash and slag from steel industry are utilized by the cement industry.A large quantity of toxic waste is destroyed by control incineration where small quantities are burn along with factory garbage in open bins.
- Urban waste:
- It consists of soil refuse containing garbage and rubbish material like paper; glass etc. These wastes emit poisonous gases, toxic hydrocarbons and microbes that cause diseases.
- Radioactive pollutants:
- Dumping of nuclear waste in soil has greater result in soil pollution.