西北农牧交错带土地利用/覆盖变化对地表水热过程的影响

土地利用/覆盖变化与地表水热过程的相互关系是当前地球系统科学研究的前沿性热点问题。本项目立足于国际地表水热过程研究前沿和西北农牧交错带生态屏障建设的重大需求，以土地利用变化对地表水热过程的影响机理和生态屏障建设的区域水热效应为关键科学问题，通过资料收集、定位监测、遥感解译、尺度拓展、陆面过程模型和区域气候-陆面过程双向耦合模型模拟等手段，揭示西北农牧交错带过去30年间不同尺度土地利用动态变化对地表水热过程的影响机理；基于土地利用变化趋势和国家生态屏障建设政策，设定不同土地利用变化情景，利用WRF-CLM4模拟分析西北农牧交错带土地利用格局变化与区域地表水热格局变化的耦合关系，为我国西北农牧交错带生态屏障建设提供理论依据和技术支撑。

Land use/cover change (LUCC) –land surface process interaction is one of the research frontiers of the earth system science. This project aims to understand the mechanism of LUCC – impacting land surface processes in the agricultural-pastoral transitional zone, Northwest China. Through acquisition of multiple databases and relevant documents, remote sensing images, and in-situ observations, the proposed project will derive dynamic LUCC maps and relevant vegetation indices such as LAI for the period of 1985-2015. In-situ observation system will be set up to monitor surface temperature, surface soil moisture, and evapotranspiration for the main land cover patterns. Subsequently, the in-situ observations and annual LUCC will be used to initialize CLM4 (Community Land Model 4) and coupled WRF-CLM4 (Weather Research and Forecasting Model – CLM4) and in turn to simulate the effects of LUCC over multiple scales on land surface water-energy exchange processes in the study region. Finally, different LUCC scenarios will be explored in the WRF-CLM4 to analyze the impacts of different green infrastructures on land surface processes and climate variability over the regional scale. Results will provide partial basis in decision/policy making for expanding green infrastructure to ensure water security and ecosystem services in the agricultural-pastoral transitional zone, Northwest China.