Excerpts from The Hindu (with inputs):
Indian soils are poor in organic matter content. About 59% of soils are low in available nitrogen; about 49% are low in available phosphorus; and about 48% are low or medium in available potassium. Indian soils are also varyingly deficient in micronutrients, such as zinc, iron, manganese, copper, molybdenum and boron. Micronutrient deficiencies are not just yield-limiting in themselves; they also disallow the full expression of other nutrients in the soil leading to an overall decline in fertility. In some regions, soils are saline. In other regions, soils are acidic due to nutrient deficiencies or aluminium, manganese and iron toxicities. In certain other regions, soils are toxic due to heavy metal pollution from industrial and municipal wastes or excessive application of fertilizers and pesticides.
Location-specific solutions to nurture soil health, increases in soil fertility etc. is needed. Soil test-based balanced fertilisation and integrated nutrient management methods combining organic manures (i.e., farm yard manure, compost, crop residues, biofertilizers, green manure) with chemical fertilizers is required.
Improvement of soil health should be a priority agenda in India’s agricultural policy. We need steps to check wind and water erosion of soils. We need innovative technologies to minimise physical degradation of soils due to waterlogging, flooding and crusting. We need to improve the fertility of saline, acidic, alkaline and toxic soils by reclaiming them. We need location-specific interventions towards balanced fertilisation and integrated nutrient management. While we try to reduce the use of chemical fertilizers in some locations, we should be open to increasing their use in other location.