Water erosion research in China: A review

Abstract. China, among other countries, suffers severe soil loss. Water erosion studies in China have been conducted since 1922, and great achievements have since been obtained. Promoting water erosion research in China and globally requires a systematic review of water erosion studies in China. This paper reviews the history, major achievements of water erosion research in China as well as its influencing factors, water erosion processes, changing mechanisms, sediment source identification, global changes, and water erosion impacts on water pollution and crop yield, and research needs in future water erosion study. Threshold slope lengths and water erosion gradients must be considered in hydrologic/erosion models to accurately estimate water erosion. Sedimentation information has been well-mined using chronological tracers and rainfall characteristics in China, which help offset the lack of monitored data in understudied regions. Physical water erosion models that have been well developed in China however should be programmed, promoted, and continuously updated to promote global accessibility. Tracers are used to estimate water erosion, and the efficiency of elemental selection and result confirmation is significant when fingerprinting methods are used to identify sediment sources. Climate change and land use models should be coupled with water erosion models to predict global change impacts on water erosion. In future water erosion research, extreme rainstorm impact on water erosion, water erosion impact on crop yield, smart soil and water conservation, and ecological service-oriented water erosion in China should be evaluated in depth. This review is intended to present water erosion research over approximately 100 years in China to provide future directions and highlight the need for ongoing water erosion research in China and other countries.