Soil fertility status as influenced by land use in Banka district of Bihar
Loading...
Files
Date
2016-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Department of Soil Science & Agricultural Chemistry, BAU, Sabour
Abstract
Increasing population pressure has historically resulted in land use change from natural forest to cultivated and grazing land with subsequent changes. Land use changes due to deforestation, conversion of rangeland to cropland and cultivation are known to result in changes in soil fertility. Handling suitable land use systems can help in sequestering carbon in the soil and ultimately decline the ill-effects of global warming. The Banka district is located in South Bihar Alluvial plain zone (i.e. Agro climatic Zone IIIA) of Bihar. The major land use types found in Banka district are forests (43310ha), cultivated land (16040 ha), grazing lands (1700 ha) and orchards (7300 ha). The agricultural productivity of Banka district is low due to undulating terrain and lack of irrigation facilities and also unstable due to extreme changes in weather conditions. The present study was planned to evaluate the effects of different land uses on the various soil fertility parameters and active pools of carbon in Banka district of Bihar. To fulfill the objective, triplicate soil samples were collected from six locations across four land use systems viz. forests, grazing, cultivated and orchards lands from two soil depths (0-15 and 15-30 cm). Results show that bulk density was highest in the cultivated land (1.59 Mg m-3) and lowest in the forest lands (1.52 Mg m-3). The aggregate stability has found in the order cultivated < grazing < orchard < forest for both surface and subsurface soil samples. The soil pH under different land uses was slightly acidic but in case of cultivated land it was approaching towards normal pH. Soil organic carbon (SOC) at the 0-15 cm and 15-30cm soil depth in the cultivated lands was 47, 23 and 13; and 37,12 and 12 per cent lower than the forests, orchards and grazing lands ; in the same order. In case of macronutrients the trend towards nutrient availability was as forests > orchards > grazing > cultivated lands. Similar trend was also observed in case of micronutrients Mn, Fe, Cu. In surface soil, Zn was the highest in cultivated land and was the lowest in grazing and orchards lands. Among the different active carbon pools, the highest water soluble carbon (WSC), water soluble carbohydrate (WSCHO), Potassium permanganate oxidizable carbon (PmOC) and soil microbial biomass carbon (SMBC) were recorded in forest soils followed by orchards, grazing and cultivated land. Overall, the soil fertility was found decline in various land use as compared to the forests.
Description
Keywords
---