Spatial Variation in Biomass and Its Relationships to Soil Properties in the Permafrost Regions Along the Qinghai-Tibet Railway

Abstract To describe the general distribution patterns in the plant biomass and its spatial relationships to the soil properties along the Qinghai-Tibet Railway, the below ground biomass (BGB), above ground biomass (AGB), species, plant coverage, soil moisture, nutrition, and permafrost table were investigated. Our independent data sets from 19 sites indicated that the communities differed significantly from each other in the vegetation types, biomass, total vegetation coverage, and species richness and composition. Overall, the mean AGB of the alpine grasslands was 0.144 kg/m2, with a greater mean value in the alpine meadow (0.183 kg/m2) than in the alpine steppe (0.060 kg/m2). AGB reached a maximum value of 0.351 kg/m2 at the Liangdao River site. Spatial patterns of soil moisture and nutrients were different from those of plant biomass; BGB was positively correlated with total nitrogen, organic matter content, and available nitrogen in the 0–40 cm soil layer and with soil moisture in the 50–100 cm soil ...