Soil Nutrients Patterns along Plant Productivity and Soil Depth Gradients under Reaumuria soongorica Shrub in Semi-arid of the Loess Plateau

摘要

It was little known about the changes in nutrients patterns along plant productivity and soil depth gradients in the Loess Plateau of China. In this paper soil moisture content, pH, soil organic carbon (SOC) and total nitrogen (TN) at three soil layers (0-10 cm;10-20 cm;20-40 cm) along 5 plant biomass gradients of a super-xerophytic shrub Reaumuria soongorica were investigated. The results showed that soil pH varied in a slightly alkaline from 7.78 to 8.22, and there were closely positive correlation between plant biomass and SOC, TN (P<0.01), and soil chemical properties were evidently influenced with higher plant biomass. SOC, TN under deferent plant biomass were highest in the top soil layer (010 cm) and decreased with soil depth, but soil moisture content increased with depth, this was probably because of not only soil drought on top jayer but also soil particle caused by soil erosion and desert plant growth characteristic.