鄱阳湖淹没范围、水深和库容的遥感研究

Study on inundation extent,water depth and storage capacity of Poyang Lake by RS

鄱阳湖湿地是国际重要湿地,也是长江的主要蓄洪区,研究鄱阳湖淹没范围、淹没水深和库容对长江流域水文和湿地保护都有重要意义。通过对13个时相的Landsat卫星遥感影像进行非监督分类提取湖泊水体淹没范围,叠加鄱阳湖区地形图,获取水体边界的水位,通过空间内插计算鄱阳湖水位空间分布,进一步计算水深空间分布和库容量,在此基础上,根据鄱阳湖都昌水文站观测水位,计算鄱阳湖水位-面积曲线和水位-库容曲线。结果表明:鄱阳湖水位存在高水位时空间一致性,低水位时水位存在较大的空间差异,湖泊水位差可达到5 m;水位-淹没面积曲线和水位-库容曲线分别可以由对数方程和二次曲线方程拟合。

Poyang Lake is main flood storage area for Yangtze River and also one of the most important wetland systems in the world.The study on the inundation extent,water depth and storage capacity is significative for wetland management and flood control in Yangtze River Basin.13 time-phase Landsat images are used to pickup the inundation extent with different water levels by un-supervision classification.The water levels at the boundary of water body are obtained by overlapping DEM and their spatial distribution is estimated by interpolation with the spatial analysis function provided by ArcGIS.Then the spatial distribution of water levels and storage capacities are calculated.On the basis of water levels measured at Duchang Hydrology Station,the relationships of water level-inundation area,and relationship of water level-storage capacity are calculated.The following results are concluded： the water level shows spatial consistency in high water level period and large difference in low water level period;the relationships of water level-inundation area,water level-capacity can be fitted as logarithmic and conic functions respectively.