中亚干旱区近50年LUCC对区域水循环蒸散发过程与格局的影响研究

土地利用/覆被变化 水循环 人类活动 蒸散发 中亚
陈曦 2008-01 项目
【英文摘要】Estimation of the magnitude, spatial and temporal variations of evapotranspiration iscentral to the analysis of regional water balances, especially for arid region in Central-Asia. Central-Asia has experienced a large-scale land use/cover change (LUCC) during the last half century due to dramatic human activity (e.g. oasis development, urbanization, hydraulic engineering construction and grazing). While we have a qualitative sense that land transformations across Central-Asia have affected regional evapotranspiration greatly, our challenge now is to quantify exactly how evapotranspiration has changed due to human-induced LUCC. Here, we propose an integrateresearch method to combine field measurement, remote-sensing data and mathematic model at multi-scale to quantify the consequences of LUCC on evapotranspiration across Central-Asia. We will document the patterns of land-use change and its characteristic across Central-Asia since 1980 to present. We will also examine how evapotranspiration have changed as a result of human-induced LUCC and climate change using integrated Dynamic Land Ecosystem Model. Model estimates along with spatial and temporal patterns of evapotranspiration will be compared to remote sensing-based model estimates one. Bothof these models will be calibrated and validated using field measured evapotranspiration. Finally, we will explore the consequence of regional evapotranspiration variation on groundwater, vegetation and lakes. The policy implication will proposed based on this study for optimizing the management and allocation strategy of soil and water resource in Central-Asia.
【中文摘要】准确测定、估算或模拟区域蒸散发的时空变化对于评价区域水文循环和水量平衡的功能,深入认识陆面水文生态过程和理解气候变化与人类活动对水循环的影响以及水资源配置与管理具有重要意义。本项目选择地表覆被和水循环发生巨大变化的亚州中部干旱区新疆和哈萨克斯坦为研究区域,通过多尺度集成点、流域、区域上的地面观测数据和遥感数据,建立干旱区基于土地利用和遥感的区域蒸散发模型和基于过程的水碳耦合模型,在区域尺度上反演研究区亚洲中部干旱区蒸散发演变过程,分析 LUCC 对该区域蒸散发时空格局的影响,探讨了人类活动对区域水循环关键因子蒸散发的影响机制,揭示干旱区人类活动对蒸散发过程与格局的影响机理,为干旱区水土优化配置提供科学基础。