水资源耗用状况分析一直是水资源管理中的一个重要环节，它直接影响着水资源供给和优化配置的合理性和科学性。近10年，研究者逐渐意识到生态环境对气候和涵养水源的重要性，因此在水资源耗用的研究中逐渐把注意力从考察生产生活水资源耗用转移到生产、生活和生态用水上，尤其在中国西北干旱半干旱地区，需要给生态水资源耗用研究赋予更高的优先级。从水分循环规律和内在机理出发研究生态系统中水分迁移过程是开展生态耗水研究的有效手段。然而，由于受到干旱半干旱地区气象水文站点少，监测数据不足的影响，研究工作集中在有资料地区。如何开展大尺度缺资料地区的水循环模拟已经成为国内外研究的热点。本文从评价所选模型在缺资料地区的适用性以及模型所需的参数和变量的获取方法两方面开展研究工作，主要研究内容和结论如下：（1）以SPAC水分运移理论为基础，确定模拟尺度和分辨率；模拟植被截留、植被蒸腾、土壤蒸发、土壤水运动和根系吸水等水分运移主要过程，选择适用于研究区且输入数据简单的模型，以减少地面监测数据对模型模拟的限制；构建遥感驱动的生态耗水模型（RS-EWCM）。（2）采用MODIS、GLDAS、FY-2、MERIS、SRTM等多源遥感数据和公共平台数据产品反演和获取气象和生态水文因子，分析了数据的精度；采用反距离加权与DEM相结合的降尺度方法对气温数据进行重采样，既考虑了高程突变带来的气温误差，也保证了局部小气候的相对独立性。分别对日平均气温和日最低气温降3℃作为最终日均气温和露点温度。（3）开展定点监测实验，为模型验证和参数率定提供数据支持；开展人工降雨实验，对该地区不同下垫面状况降雨入渗产流机制有了定性认识；开展土壤水力特性实验和植被调查，获取土壤水力特性参数和植被参数为模型模拟提供数据支持。（4）以中国西北干旱半干旱缺资料地区——新疆伊犁河流域为例，耦合多源遥感数据，推求适用于该流域的模型参数，模拟伊犁河流域生态耗水量，验证模型精度，并进行伊犁河流域境内外生态耗水分析。伊犁河流域多年平均生态耗水量为 亿立方米。在境内外天然植被面积相当的情况下，境内外生态耗水总量差值在逐年扩大，除去境内农田生态耗水比境外多的部分，生态耗水量仍是境内大于境外，这是由于伊犁河流域境内天然植被单位面积耗水量比境外大。与生态需水相结合，评价了伊犁河流域生态补水状况。第六号子流域农田覆盖面积大，是主要耗水区域，又因水分补给不足，该子流域为需补水级别最高区域。

Analysis of consumption of water resources is always a very important part in water resources management. The analysis directly affects the rationality and scientificalness. In recent decades, researchers began to realize the importance of ecological environment in climate change and water conservation. Therefore, the research focus on water resource consumption has turned from the aspects of production and life to the aspects of production, life and ecology. Especially, we should set higher priority to the research of ecological water use in arid and semi-arid region in Northwest China. It is an effective way to study the process of water movement in ecosystem based on water cycle mechanism. However, due to the sparse observed data from sparse weather station and hydrological station in arid and semi-arid region, research work generally concentrates in the basins which have enough observed data for hydrological modeling. In this condition, how to carry out water cycle modeling in large scale has become a hot point in ecohydrological research. This paper tries to improve the research work in ungauged basins in two aspects. One is evaluating the applicability of the selected models in ungaued basin. The other is create methods to obtain parameters or variables in eological water consumption models. The main research content and conclusion are shown below.(1) Based on theory of water movement in SPAC system, the study selected models which are suitable for ungaued basin and need less input parameters to reduce the dependence of model parameters on observed data and constructed a remote sensing driven ecological water consumption model (RS-EWCM). After setting modeling resolution, the study simulated the process of water movement in canopy interception, plant transpiration, soil water evaporation, soil wate movement and plant root water uptake. (2) The study Applied multi-source remote sensing data and products, like MODIS、GLDAS、FY-2 and SRTM, on inversing and obtaining meteorological, ecohydrological parameters and analyzed the data precision. On consideration of error of air temperature in high elevation area and maintain the relative independence of air temperature in different local areas, the study designed a method that combining Inverse Distance Weighted method and DEM to do air temperature downscaling. After data precision analysis, the study substracted 3 °C from daily and minimum air temperature as final daily air temperature and dewpoint temperature.(3) The study also carried out in-situ meteorological and ecohydrological monitoring to support validation and calibration. Artificial rainfall experiment helped to know the mechanism of the rainfall-infiltration-runoff in different land surface type in study area.(4) The study served Ili river basin, which is a typical arid and semi-arid ungaued basin, as study area. The study estimated suitable parameters, simulated ecological water consumption in Ili river basin, carried out simulated result validation and analyzed the variation of ecological water consumption under yearly land cover change. The average yearly ecological water consumption is m3 in the whole basin in plnat growing season. The ecological water consumption in inside part of the basin is higher than that in the outside part, and the difference is wider year by year. After analysis, this trend is mainly due to the different value of ecological water consumption per unit area between the outside and inside part of the basin. Combining the simulated result of ecological water requirement, the study analyzed the difference between ecological water requirement and ecological water consumption. Based on the difference, 4 levels of ecological water shortage were classified. The No.6 subbasin, which contains the largest crop area among all subbasin, has the highest level of ecological water shortage.