Soil microbial biomass plays an important role in nutrient transformation in terrestrial ecosystems. Microbial biomass is also an early indicator of changes in total soil organic carbon. Thus, the main objective of this study was to identify and quantify the present status of soil microbial biomass carbon and nitrogen with various management practices in Himalayan rangeland. To meet the aforementioned objectives, a field study was conducted in Tinjure Milke Jaljale (TMJ) eastern Himalaya Nepal in 2011-2013. Soil samples were collected from the depths of 0-15 cm at three soil cores in each quadrat. Quadrat size was 30*30 cm and core size was 4 cm in diameter and 15 cm deep. Composite soil sample was made while mixing all the samples of a quadrat. Five quadrats were taken from each subplot. Soil core was separated into three sections viz. 0-5, 5-10 and 10-15 cm profiles with 5 cm length of each slice. Soil sample analysis was carried out by the process of chloroform fumigation method. The Result showed that soil microbial biomass C ranged from 219.84 to 987.5 mg/kg. The soil microbial biomass C was increasing with decrease of grazing intensity of the rangeland and differences were significant. Similarly, the soil microbial biomass N with value of 207.72 mg/kg was significantly higher in occasional grazing plot than two other treatments. Both soil microbial biomass C and N values were in decreasing trend with increase of soil depth of the rangeland. پرونده مقاله

The most important environmental driver is the elevation in mountain ecosystems. It strongly influences the distribution of species richness. Species richness is an indicator of the biological diversity and ecological condition of the area. To understand the status of phytomass, species diversity, and physico-chemical properties of soil along the altitudinal gradient and its influence on the interrelation between phytomass, species diversity, and physicochemical properties of soil. To know the correlation between plant species and environmental factors.We used a transect line method to enumerate the plant community in each sampling plot. Phytomass was estimated by the total harvesting method. Soil properties were determined with standard methods, viz., Blake and Hartge (1986), Chromic Acid Wet Oxidation Method, and Kjeldahl method. SPSS and R programming were used for data analysis.Plant diversity indices, viz., Shannon-Wiener diversity index, Simpson's dominant index, Pielou’s index, and Margalef index were highest at the low altitude and the lowest value at high altitude. AGB, BGB, SOC and STN were highest in high altitude (Jaljale). Phytosociological indices and environmental factors, except moisture and SBD, were high at high elevation. The first axis of ordination was positively correlated with SBD, moisture, ABG, and BGB and negatively with STN.The low-altitude rangelands have high anthropogenic activities; grazing, trampling, and burning disturbed the natural storage of organic carbon, nitrogen, phytomass, and diversity. The study showed a linear negative relationship between phytomass and altitude. پرونده مقاله