Land use effects on soil organic carbon stocks in the submontane areas of north-western Himalayas, India

Abstract

A study was conducted to assess the impact of soil organic carbon stock under different land use systems in submontane areas of north-western Himalayas India. Soil samples were collected from the five landuse systems viz: forest, horticulture, agriculture, pasture and degraded land to a depth of 1 m. Soil physical-chemical properties reveal that the soil bulk density in the surface soil (0-15 cm) was maximum in degraded (1.54 g cm-3) and the least in pasture (1.32 g cm-3) and forest (1.33 g cm-3), landuse systems, respectively. The bulk density recorded at the surface soil layer (0-15 cm) was found to be significantly lower than the subsurface soil layer 15-30 cm, 30-60 cm and 60-100 cm). Soil bulk density increased with soil depth. In the surface soil the maximum organic carbon concentration was found in the pasture (7.57 g kg-1) and the least (5.01 g kg-1) in degraded landuse systems. The soil organic carbon concentration was decreased with increasing soil depth. Forest and degraded landuse systems displayed the maximum value of soil organic carbon stock (15.40 and 14.59 Mg ha-1) in 0-15 cm layer and the least (12.97 Mg ha-1) in pasture. Soil of soil organic carbon stock in surface soil is 1.32 times higher in subsurface soils. Soil organic carbon stock in 0-15 cm layer was found to be significantly higher than that of 15-30 cm layer. The highest soil organic carbon stock (0-100 cm) layer was observed in forest land (53.38 Mg ha-1), and was least in agriculture (42.09 Mg ha-1) landuse systems. The present study indicates that forest system is a better option to enhance the SOC stocks in the submontane areas.