Soil carbon stocks in India – Issues and priorities.

Abstract

Management of soil health is a major concern, particularly in the soils of the tropics. Natural as well as anthropogenic activities enhance the degradation of soil organic carbon which is the single most important soil parameter for maintaining soil health. This demanded that the knowledge of soil carbon stock is essential for proper management interventions for priority areas to make our soils resilient. The methodology adapted for the calculation of soil carbon stock of India, included relevant soil organic carbon (SOC), bulk density (BD) and calcium carbonate equivalent (SIC) data used from published and unpublished soil database generated through soil resource mapping of India by ICAR-NBSS&LUP, Nagpur at 1: 250,000 scale, at 1: 50,000 scale and from other sources. The soil carbon stock was computed using simple formula of various depths varying from 0-0.3, 0-0.5, 0-1.0 and 0-1.5 m depths and expressed in pentagram, Pg (1Pg=1015g). the carbon stocks were computed at various depths as SOC, SIC and total carbon (TC). The variations were expressed in different grouping of soils such as in soil orders, Indian soil classification types, bioclimatic zones, major soil groupings, semi-arid tropical regions etc. the total carbon stock of India in the 0-0.3 and 0-1.5 m were estimated to be 9.55 and 29.92 Pg, respectively. The paper also discusses the outputs of Century C and ZEFSOC (Global Environmental Fund Soil Organic Carbon) modelling systems, carbon trading and the usefulness of soil carbon stock data.