Impact of Land Use/Land Cover on Soil Carbon and Nitrogen Fractions in North-Eastern Part of India

Land use/land cover (LULC) plays a pivotal role in maintaining the carbon (C) and nitrogen (N) balance in the ecosystem. It is also important for controlling soil organic carbon (SOC) levels by affecting the quantity and quality of below- and above-ground litter inputs and subsequent decomposition. The aim of the present study was to understand the effect of LULC on the C and N fractions and their stocks in the Eastern Himalayan floodplain. The study was conducted at the Pundibari campus of Uttar Banga Krishi Viswavidyalaya, Cooch Behar, West Bengal, India, hosting four kinds of land uses – agricultural croplands, grasslands, plantation croplands and human-interfered lands. The soils were acidic (pH 5.13–5.68) irrespective of the LULC type and low in bulk density (1.02–1.27 g/cm³). Estimation of seve­ral forms of C and N, viz. SOC, total C, available N, ammoniacal N, nitrate N, total N, C stock, N stock, etc., indicated variations in these forms under different LULC types. Significant variations (P < 0.05) were found for SOC and ammoniacal N content in different LULC types. Both mean C and N stocks were found highest in grassland soils (18.91 and 2.64 t ha^–1 respectively), follo­wed by plantation croplands (17.24 and 2.41 t ha^–1 res­pectively).