What are the various causes of soil degradation in India? Discuss some relevant methods of soil conservation? What is the proposed Second green revolution in India?
Soil degradation refers to decline in the soil’s productivity through adverse changes in nutrient status, soil organic matter, structural attributes, and concentrations of electrolytes and toxic chemicals. Soil degradation is a process, which lowers the current and/or future capacity of the soil to produce goods or services
Soil degradation is a process in which top layer of soil loses its quality owing to both natural and anthropogenic factors
Causes of Soil Degradation In India:
The land degradation is caused by excessive pressure on land to meet the competing demands of the growing population for food, fodder and fibre. Various human activities, such as the introduction of large scale irrigation canals, deforestation and faulty land use lead to accelerated soil degradation through salinization, flooding, drought, erosion and waterlogging. These processes, in turn, reduce agricultural productivity leading to social insecurity. Emission of greenhouse gases to the atmosphere resulting into the global warming could be the major reason for soil degradation.
Major causes of soil degradation
Decline of soil fertility
Among the agents, water is considered as the main cause of soil erosion.
Main agents of soil erosion are (1) Water, (2) Wind, (3) Waves and (4) Glaciers
Removal of the top layer of soil by various means, which include both natural events and human activities, is called as soil erosion.
Consequences of soil erosion
→ Fertility of top soil will be lost.
→ Nutrients content will decline as they are washed away by erosion.
→ Underground water level will be reduced.
→ Loss of vegetation and habitat.
→ Drought and flood become frequent.
→ Rivers get dried off.
→ Adversely affect the economy and culture.
→ Natural hideouts are formed when gully erosion occurs (Ex: Chambal valley was famous for criminal’s hideout).
→ Water logging-If there is no proper drainage system in the land, the land will become waterlogged.
→ This results in the saturation of crops.The normal circulation of air will not be possible due to water logging and the amount of oxygen in the soil will decline.Construction of proper drainage system to allow water flow away from the land is the best way to reduce water logging.
Soil will become saline or alkaline in low rainfall areas. Rajasthan is an example.
When the sea water enters the land, the soil becomes saline.
The presence of calcium carbonate beneath (kankar) the soil will act as impermeable to water and water gets logged as happened in Indira Gandhi canal regions of Rajasthan. If the soil contains salt content, it will spread to the whole land due to this.
Shifting / jhum cultivation
It is a type of cultivation practiced mainly in North-Eastern states of India It is a type of slash and burn method of cultivation.
After reaping the crops, the land (usually the forest) is slashed and burned. The next cultivation will be in another plot and the burned land will let uncultivated for a period.
In the early periods, the gap between two cultivations in a land was 10-20 years.
Due to population increase and availability of land is reduced, the gap decreased to merely 2-3 years.
This causes major deforestation, environmental pollution, loss of habitat for wild animals etc.
The burning of forest results in soil erosion and gradual degradation of soil.
Soil conservation methods
Afforestation-Afforestation drives need to be encouraged at the private and public levels.
Contour ploughing (cultivation against the direction of the wind)-This can be a major method of soil conservation where wind is the chief culprit. Planting of trees along the fences can complement the method further.
Strip cultivation (cultivation in strips).
Flood control by government initiatives-The control of floods with various initiatives such as strengthening of infrastructure, better control of dams, etc can aid in soil conservation.
Reclamation of bad lands-Badland and ravine topography such as the floodland of Chambal river can be reclaimed to prevent further erosion of top soil.
Wind breaks in land; like trees at borders.
Organic farming- In addition to preserving the health of the soil by the use of sustainable practices and bioorganisms, it can also prevent soil erosion by using methods such as soil conservation.
Control/restrict shifting cultivation-‘Jhoom cultivation’ practised especially in the Hilly regions of North East India, is a traditional farming practise causing much harm to the soil. This should be controlled by training the locals with modern practices of cultivation.
Construction of proper drainage.
Leveling of gullies, ravines etc.
Control of chemical fertilizers and pesticides in the market.
Second Green Revolution in India
It is being realized that original means adopted by green revolution are to some extent exhausted and have resulted in degradation of land and drying of water tables.
The resulting state of agriculture is not sustainable at all. Consequently, new agriculture policy of India aims at sustainable agriculture, which is popularly called ‘second green revolution’ or ‘Evergreen Revolution’.
Almost every current policy can be covered under category of second green revolution. It aims at information technology revolution, bio technology revolution, R&D and targeting of specific crops etc.
Information Technology will create awareness in farmers, introduce them with more cost efficient technologies and enable them to choose among different alternatives.
Bio technology revolution aims at improving genetic traits of crops, by making them draught, pest, weed, climate resistant. This is to be done by genetically engineered crops, by continuously improving them.
Another aspect of Second Green revolution is use of bio pesticides and bio fertilizers. This is actually part of bigger strategy targeted towards organic farming.
Organic Farming in India
Organic farming system in India is not new and is being followed from ancient time. It is a method of farming which is primarily aimed at cultivating the land and raising crops in such a way, as to keep the soil alive and in good health by use of organic wastes (crop, animal and farm wastes, aquatic wastes) and other biological materials along with beneficial microbes (bio fertilizers) to release nutrients to crops for increased sustainable production in an ecofriendly pollution free environment.
It is worth mentioning that, north eastern India has highest potential for organic farming. It has distinct agro- climatic zone and its soil is immensely rich in organic matter. Further, it was aloof of any green revolution and consequently farmers there still use traditional methods. All this obviously is perfect opportunity for promoting organic farming rigorously in the north east.