Wang Yunqiang1, Shao Mingan2, Hu wei3, Henry Lin4, HuangHui5
（1. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, Shaanxi 710075, China;
2. Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China;
3.University of Saskatchewan, Department of Soil Science, Saskatoon, SK S7N 5A8, Canada;
4. The Pennsylvania State University, Department of Crop and Soil Sciences, USA, PA 16802; 5. Hunan Normal University College of Resource and Environment Science, Changsha, Hunan 410006, China）
Abstract: The critical zone (CZ) where occurred series of physical, chemical and biological processes closely related to human activities, is essential for the survival and development of mankind. Soil water content (SWC), which plays a key role in the earth’s CZ, is a dominant factor of vegetation restoration and eco-environment reconstruction on the Chinese Loess Plateau. To determine the spatial variations of SWC in the CZ of the Loess Plateau, we selected 73 sampling sites at a small catchment with a grid of 50 m × 50 m, and collected soil samples to a depth of 500 cm after a rainy season. Results show that the values of all measured SWC range from 1% to 23%. The SWC located at 0-100 cmdepth is highly replenished by rainfall. SWC demonstrates an obvious spatial heterogeneity both in the horizontal and vertical direction, which is controlled by different processes in different directions. Spatial pattern of SWC is the combined effect of land use and vegetation type, tographical elements and soil texture. Understanding this information is helpful for the planting and layout of vegetation at a catchment scale, and also for investigating the soil hydrological and biogeochemical processes in the CZ of the Loess Plateau.
Keywords: Loess Plateau; Earth’s critical zone; soil moisture, land use; spatial variability
EARTH AND ENVIRONMENT Vol.44, No.4 Tot No.312, 2016, Page 391-397
