东辽河流域坡面系统生态需水研究

Ecological Water Demand by the Slope System in the East Liaohe River Basin

以东辽河流域累积46个测站52年的水文资料和1986年、1996年、2000年Landsat TM数字图像为源信息,在分析景观格局、流域降水和径流时空分布的基础上,探讨东辽河流域坡面系统生态需水的时空变化和平衡分区。东辽河流域坡面系统景观的优势度较强,斑块的形状较为规整,但分布较散,同时受到人类活动的干预非常强。水文情势的空间分异明显。东辽河流域坡面系统全年平均生态需水量为504.72 mm (324.08 mm^618.89 mm),5～9月份生态需水量占全年生态需水总量的88.29 %,下游形成生态需水的高值区。坡面系统生态需水量的极端满足程度仅为90 %,全年和生长季(5～9月) 生态缺水区分别占了全流域总面积的60.47 %和74.01 %,从生态需水的缺水数量和缺水区域来看,缺水区域大的趋势尤为严峻,必需采取全流域用水的综合调配。

Based on GIS and RS with the source information of hydrological data of 46 hydrological monitoring stations during the 52 years and the digital imageries of Landsat TM in 1986, 1996 and 2000, the landscape patterns, precipitation and runoff in the East Liaohe River Basin were analyzed. With the result of the above analysis, the spatial and temporal changes of the ecological water demand (EWD) in the slope systems of the East Liaohe River Basin were derived. Landscapes in the East Liaohe River Basin have great dominance and the standard form, however, the distribution of the landscape in that basin is disperse and strongly disturbed by human activities. The hydrological regime has distinct spatial variations. The annual average EWD of the slope system in the East Liaohe River Basin over years is 504.72 mm (between 324.08 mm and 618.89 mm), and that in the growing period (between May and September) is 88.29% of that of the whole year with the lower reaches of the basin facing crisis of the EWD. The ultimate satisfaction of the EWD of the slope system is 90%. The areas lacking of the EWD in the whole year and in the growing period are 60.47% and 74.01% of the whole basin, respectively. The trend of area lacking of the EWD is particularly serious with respect of the quantity and area lacking of the EWD.