Spatial variation of soil properties and carbon under different land use types on the Chinese Loess Plateau.

Land-use affects soil properties and soil carbon storage. Fully understanding land-use impacts on soil is essential to predicting effects on soils from climate change, and providing a scientific basis for soil management. Here, we measured soil properties, soil organic carbon (SOC), soil inorganic carbon (SIC) and total carbon (TC) from 202 samples from cropland, forestland, and grassland, to a depth of 500 cm on the Chinese Loess Plateau (CLP). We find that grassland and cropland have the highest clay and silt content, and have a significantly higher soil moisture capacity than forestland. Soil moisture in forestland is scarce at depths of 100-300 cm, and does not benefit from rainfall infiltration. At the same time, the soil carbon content and stocks in grassland are not significantly different from forestland. We suggest that in the light of climate change and water shortages on the CLP, grassland is more suitable than forestland or cropland to optimize carbon fixation, and prevent soil erosion. Hence the cultivation of grass should be considered as a strategy for sustainable ecosystem management on the CLP.