遥感水分收支对区域水资源估算潜能

Potential of Remote Sensing-based Water Budget for the Estimation of Regional Water Resources

为获得遥感水分收支对区域水资源估算潜力,利用遥感降水与蒸散发数据,通过研究中国十大水资源一级区及省区尺度上遥感水分收支平衡(降水与实际蒸散发差值)与水利统计水资源量间的关系.发现遥感降水蒸散差折合水资源量与基于统计数据的水资源量间具有较强正相关性,但总体偏低且存在区域差异,其中海河区低估最为显著,其次为淮河区、西南诸河区,西北诸河区则存在较大高估。对于地下水需求较大的区域,如海河区,地下水开采量没有被考虑作为遥感水资源量来源是造成遥感水资源量低估的主要原因。遥感降水低估、蒸散发高估也导致遥感水分收支平衡折合水资源量低于基于统计数据的水资源量。水资源时间变化趋势显示,中国水资源量总体呈增加趋势,但作为粮食主产区及人口密集区的华北地区,水资源形势严峻,呈显著减少趋势,将对经济发展及人们生活产生重大影响。

To obtain the potential of remote sensing-based water budget for regional water resources estimation,this study analyzed the correlations of the difference between remote sensing-based precipitation and evapotranspiration and water resources from the statistical data in China at the water resources sub-region and provincial scales.The results concluded that there is a strongly positive linear relationship between remote sensing-based water budget and statistic-based water resources,but the estimation from remote sensing is generally lower than the statistic-based values.The underestimation at Hai river basin is more serious,then is Huai river basin and southwest river basin,while the northwest river basin is overestimated.For those regions with a large amount of groundwater use demands,e.g.,Hai river basin,groundwater exploitation is not considered as the source of remote sensing-based water resources,which is the main reason leading to the underestimation of remote sensing-based water resources.The underestimation of remote sensing-based precipitation and the overestimation of remote sensing-based evapotranspiration also lead to the remote sensing-based water resources lower than statistic-based water resources.There is an insignificant increasing trend for the water resources of the whole China.However,the water resources of North China region significantly decrease because of the large demands of crop and people for water,which will be adverse for economy development and people living of this region.