Competing uses of land for forestry, agriculture, pastures, human settlements, and industries exert pressure on the finite land resource influencing land-use patterns and sometimes causing degradation. Changes in land use and land cover, and land degradation, have adverse impacts on forest resources and biodiversity. Given that they are intertwined in various ways, there is a need for treatment of land, forests, pastures, and biodiversity as an integrated resource.
India supports approximately 16% of the world’s population and 20% of its livestock on 2.5% of its geographical area. This pressure on land has led to its deterioration—soil erosion, water logging, salinization, nutrient depletion, lowering of groundwater tables, and soil pollution—largely caused by human interventions.
Soil erosion has led to loss of topsoil and terrain deformation. Siltation, an off-site effect of erosion, is reducing the reservoir storage capacity by 1%–2% annually.
Human-induced water logging is resulting in a rise in the water table. ?
Salinization is likely to render more land unfit for biomass production, especially in the irrigated areas in Uttar Pradesh, Haryana, Punjab, Rajasthan, and Karnataka. ?
Most regions have a net negative balance of nutrients and suffer from a gradual depletion in the level of organic matter, a trend that is likely to continue. Maintaining the nutrient balance and preventing nutrient deficiencies is a major concern given that the required demand for food production will have to be met through increased intensity of cropping (Sehgal and Abrol 1994). ?
Over-extraction far exceeding recharge in areas where groundwater is mostly used for industrial and agricultural purposes, has led to progressive lowering of water table affecting the economy of water in use and the environment. ?
Improper and indiscriminate use of agrochemicals and untreated sewage sludge and municipal wastes has led to the pollution of soil and water with toxic substances and heavy metals.
At present, 40% of the commercial demand for timber and less than 20% of the demand for fuel wood are being met by sustainable supply from forests. Paucity of funds and other resources will lead to an inadequate emphasis on superior quality planting material and improved practices resulting in marginal increase in wood yield of forests.
The future demand for both commercial timber and fuel wood will, therefore, not be met sustainably from the wood produced from forest and tree cover; even though people’s preferences will move up the energy ladder with the availability of a range of substitutes for fuel wood.
In India, an average of 42 animals graze on a hectare of land, compared to the threshold level of 5. Thus, nearly a third of the fodder requirement is met from forest resources in the form of grazing and cut fodder for stall-feeding. An estimated 100 million cow units graze in forests annually against a sustainable level of 31 million.
Additionally, graziers collect 175–200 million tonnes of green fodder annually. Grazing affects approximately 78% of India’s forests (FSI) and occurs even in protected areas. Over-grazing and over-extraction of green fodder lead to forest degradation through decreased vegetative regeneration and, through compaction of soil, to reduced infiltration and vulnerability to erosion.
In the BAU scenario, inadequacy of grazing land will be more acute and forests will continue to be used for grazing extensively.
India’s biodiversity is being gradually decimated. Maintaining viable populations of species, whether plant or animal is crucial in biodiversity conservation requiring the conservation of important ecosystems, habitats and the ecological processes of which they are part. According to IUCN, the World Conservation Union, 5% of a country’s area should comprise PAs.
India has almost achieved this target and given the intense pressures on land and forests, there is only a limited scope to increase the area under parks and sanctuaries. Currently, the PA network does not adequately cover some important biomes and species of conservation significance. It is, therefore, recommended that the area under parks and sanctuaries be increased to 160 national parks and 698 sanctuaries.
Since the number of protected areas cannot be increased substantially, the next question is of size of the reserves. Ideally, an effective conservation area should be large enough to ensure that all target species have genetically viable population sizes and that ecological processes are maintained.
In general, therefore, the thumb rule is to have areas as large as possible to maintain viable population sizes and if not, make do with what one has and manage the area intensively. This can be done, for example, by ensuring genetic viability by the creation of corridors, translocation and restocking, ensuring effective conservation of the surrounding reserve and protected forests including buffers.
Further, the portions of dense forests other than PAs, are also important for maintaining the extant biodiversity, a significant proportion of which lies outside the PA network.