Abundant inorganic carbon shows soil is degrading
doi:10.1038/nindia.2007.38 Published online 26 December 2007
While India's agricultural management practices post the Green Revolution have helped take good care of soil organic carbon (SOC), an essential for good crop yield and productivity, they have not been able to arrest the simultaneous increase in soil inorganic carbon (SIC) content levels over the last 25 years, new research says1. This suggests the initiation of chemical degradation in India's soils, the study warns.
Soil scientists studying datasets for 1980 and 2005 in two important crop zones of the country have found that the SOC stocks had increased significantly during these years. However, the SIC stocks were more than SOC in these regions. "This assumes importance since it signals the beginning of soil degradation," says Tapas Pal, one of the researchers.
The team studies the Indo-Gangetic Plains and the black soil region in the semi-arid tropics. The study suggests that soil containing huge SIC stocks can be managed by improving the vegetative cover. "This offers two fold gains – sequestration of organic carbon in soils through plants and dissolution of soil carbonates by root exudates improving soil structure to enhance drainage," Pal says.
The authors of this work are from: National Bureau of Soil Survey and Land Use Planning, Napgur, India; International Crop Research Institute for Semi-Arid Tropics, Hyderabad, India
- Bhattacharyya, T. et al. Changes in levels of carbon in soils over years of two important food production zones of India. Curr. Sci. 93, 1854-1863 (2007).