半旱区草原沙化是我国最主要的生态问题之一，尽管研究表明过渡放牧、不合理的农垦和气候变化是沙化的主要原因，但与沙化过程密切相关沙地水热通量传输过程及其与植被生态间的耦合作用机理仍不明确。本项目以我国半干旱区典型沙地——科尔沁沙地为研究区，选取其典型生态系统沙丘和丘间草甸为研究对象，通过微气象、涡度相关和遥感技术，采用野外试验、数据分析和遥感反演相结合的研究方法。以研究水热通量在沙丘和丘间草甸地气界面间的传输机理；分析能量通量与蒸散发、土壤水分、地下水位和潜水蒸发间的耦合作用关系；并通过构建基于遥感的水热通量估算模型来揭示沙丘和丘间草甸生态系统水热通量分布特征和时空变化规律，最终结合遥感植被特征参数探讨水热通量与植被间的耦合关系。本研究将揭示沙地水热耦合伴生关系与运移机制，明确水热通量和各能量分量与植被间耦合关系，对丰富完善沙地生态水文学理论有重要意义，也可为退化生态系统恢复重建提供科学依据。

The grassland desertification in semi-arid region is one of the most important ecological problems of China. Even though studies show that overgrazing, irrational agricultural reclamation and climate change is the main cause of desertification, but one of the basic researches which has closely related to desertification process is still unclearly. The research is water heat flux transfer process and it coupling mechanism with vegetation in sandy land. In this project the Horqin sandy land well be selected as the study area, which is the typical sandy land in semiarid area of China.The sand dunes and inter-dune meadow are selected as the research object for they are both the typical ecosystem of Horqin sandy land. The micrometeorology, eddy covariance, and remote sensing technology were used as observation technologies. Field test, data analysis, and remote sensing retrieval are combined as research methods. With these methodologies the water and heat fluxes transmission mechanism between interfaces of soil and atmosphere will be study in the dunes and inter-dune meadow ecosystem. The coupling effect relationship of energy fluxes with evapotranspiration, condensation water, groundwater level and phreatic evaporation will be research too. Then, a sandy land water and heat fluxes estimation model will be developed build based on the remote sensing data in order to research the distribution and temporal variation, and reveal the coupling relationship between the water and heat fluxes with ecosystem of dunes and inter-dune meadow. This study will rich and perfect the theory and techniques of sandy ecohydrology study, reveal sandy hydrothermal coupling associated relationship and flow mechanism has important practical significance for the sustainable maintenance of the ecosystem of Saudi degraded ecosystems restoration and reconstruction to provide a theoretical basis and technical support.This study will reveal the water heat coupling associated relationship and transmission mechanisms in sandy land. The study results will not only rich and perfect ecohydrology theory and technology in sandy land but they also provide theoretical and scientific bases for preserving natural sandy land ecosystems, and restoring degraded ecosystems in sandy land.