土壤水分是喀斯特地区植被生长重要的水分来源，研究土壤水分时空变化对当地石漠化治理和生态重建具有重要意义，而其中土壤水分的测定又是关键环节。传统土壤水分测定方法虽然精确，但在大尺度上却有明显不足。而卫星遥感则能快速、大面积地获取地面信息，已成为土壤水分测定最有效的手段之一，应用十分广泛。然而，目前在喀斯特地区土壤水分遥感反演方面的研究仍处于起步阶段。针对这一问题，本研究以定位观测和地面调查为基础，以期建立适用于喀斯特地区的微波遥感（RADARSAT-2）土壤水分反演模型，并用其揭示喀斯特地区土壤水分时空变化规律及其影响因素，为喀斯特地区水资源管理和石漠化治理提供支撑。

Soil moisture is the foundational water resource for the vegetation in karst area,hence, study of the spatial-temporal variation of soil moisture is essential forecological reconstruction. Although it is accurate, conventional soil moisture monitoring methods have some obvious disadvantages, especially in monitoring soil moisture for large areas. Microwave remote sensing technology has demonstrated aquantitative, economical and time saving advantage in measuring soil moisture under a variety of topography and vegetation cover conditions and large space scale, particularly for bad weather conditions. Inversing soil moisture using remote sensing has been applied and studied widely, however, the relevant studies in karst region are still rare. The main objectives of this project are to establish applicable models (RADARSAT-2) for soil moisture inversion, and to investigate the spatial-temporal variation of soil moisture and the influencing factors in typical karst catchment. This project would provide the knowledge for reasonablely managing water resources and deep understanding of the soil water distribution and movement, and would also be helpful for ecological restoration.