Active and Passive Soil Organic Carbon Pools as Affected by Different Land Use Patterns in Red Soils of Vikarabad District, Telangana, India

Abstract

A survey was conducted in the years (2019-20 and 2020-21) in red soils of Vikarabad district covering eight mandals and soil samples were collected from four predominant land use patterns at two depths (0-15 and 15-30cm). Land use patterns studied included cultivated land with different cropping intensity i.e., 100% cropping intensity (redgram-fallow), 200% cropping intensity (rice-rice) and two from natural conditions i.e., forest land and fallow land to assess the impact of these land uses on various pools of SOC viz., total organic carbon (TOC), oxidizable organic carbon and its pools. The SOC content of forest land recorded the highest mean value (7.30 g kg-1) and that of fallow land recorded the lowest value (2.24 g kg-1).The mean SOC stock was highest in forest land (13.92 Mg Cha-1) and that of fallow land was the lowest (5.64 Mg C =ha-1). The highest accumulation of mean TOC was observed in forest (26.28 Mg ha-1). The per cent contribution active carbon pools to TOC was highest forest land (54.33 %) followed by redgram-fallow 53.16 %, suggesting that the accumulated carbon could be easily lost following the land use change. Contrarily, the per cent distribution of TOC to passive carbon pool was highest under fallow land (54.96 %) and rice-rice cropping system (52.00%) indicating more stable nature of the accumulated organic matter.