Changes in levels of carbon in soils over years of two important food production zones of India

It is realized that the carbon content in soils changes depending on the land use system and time. There is an increasing concern about the decline in soil productivity and the impoverishment of soil organic carbon (SOC) caused by intensive agriculture. The National Bureau of Soil Survey and Land Use Planning, Indian Council of Agricultural Research, through organized research initiatives, sponsored by national and international organizations, has developed datasets SOC and soil inorganic carbon (SIC) for two important crop production zones, viz. the Indo-Gangetic Plains and the black soil region in the semi-arid tropics. The datasets for 1980 and 2005 indicate an overall increase in SOC stock in the Benchmark spots under agriculture, practised for the last 25 years, although the level of SIC has increased indicating an initiation of chemical degradation. This suggests that the agricultural management practices advocated through the national agricultural research system for the last 25 years did not cause any decline in SOC in the major crop-growing zones of the country