Soil microbial biomass phosphorus under different land use systems of Central Himalaya

Cultivation leads to a considerable loss of soil nutrients and microbial population. Previously, only the soil physico-chemical properties were achieved attention to assess the status of soil nutrients but nowadays, the role of soil biodiversity are also considered in sustaining the soil fertility and crop production. Therefore, the present study evaluated the impact of different land use patterns on soil health including physical, chemical and biological properties along the altitudinal gradient in Indian Central Himalaya. The soil samples were collected from five predominant agricultural land uses including (1) open cropland (OpC), (2) cropland with multiple tree species (C + mT), (3) cropland with single tree species (C + sT), (4) Homegardens (HG) and (5) Agriculturally discarded land (ADL). The various physico-chemical and biological properties of the soils were determined with the standardized methods. The physico-chemical properties showed the significant differences with land use systems and altitudinal variation. Among the different systems, the highest values of soil phosphorus and phosphorus stock were recorded in C + mT system (0.042% and 0.73 t ha(-1)) whereas lowest in ADL system (0.033% and 0.59 t ha(-1)). The range of microbial biomass phosphorus and microbial quotient varied from 18 (OpC) to 25 mu gg(-1) (C + mT) and 4.92 (OpC) to 6.18% (ADL), respectively. The highest microbial biomass phosphorus (MBP) was recorded in the lower altitudinal region of Tarai and lowest was recorded in the higher altitudinal region. Across the seasons, it was maximum recorded during the rainy and minimum during the winter season. Soil MBP showed the significant correlation with altitudes, systems, abiotic variables, physico-chemical properties of soil and vegetation. This study concludes that tree based systems should be preferred as an agriculture management practices to promote microbial diversity, their activities and soil quality enhancement in the Central Himalayan region.

Automated summary

Cultivation causes significant loss of soil nutrients and microbial population, with attention shifting towards the role of soil biodiversity in maintaining soil fertility and crop production. Tree based agriculture management practices are shown to enhance microbial diversity, activities, and soil quality in the Central Himalayan region.