基于GF_1卫星的丹江口水库水面面积-蓄水量-水位相关性研究

基于GF_1卫星16m分辨率多光谱遥感数据及水文观测数据,通过计算NDWI水体指数来提取丹江口水库水面面积,并研究水面面积、水位与蓄水量三者之间的相关性,实现动态分析水库蓄水量变化情况,以期为"南水北调"提供决策支撑。研究发现:(1)南水北调中线首个调度年前后丹江口水库水面面积-水位,水位-蓄水量以及水面面积-蓄水量之间均为显著相关关系,且三对变量依次呈现明显的1次、2次、3次曲线关系,拟合曲线方程的决定系数分别达到0.976、0.999和0.980,因此可以根据其中一个已知变量预测其他两个未知量;(2)水面面积自2014年10月5日至2016年5月5日最大变化幅度相差180km~2,是影响周边环境变化的重要因素;(3)同时蓄水量在首个调度年内,于2014年11月初达到最大值204.10亿m~3,可调水量在16.53~78.93亿m~3范围内浮动,且年内整体变化平缓稳定,保证了2015调度年内南水北调中线工程的供水需求。

Correlation study on water area- capacity-level of Danjiangkou Reservoir based on GF_1 Satellite

Based on the GF-1 Satellite's 16m-resolution multispectral remote sensing data and hydrological observation data,we extracted the water surface area of the Danjiangkou Reservoir by calculating the Normalized Difference Water Index (NDWI),and studied the correlations between water surface area,water level,and water storage,realizing dynamic analysis of the reservoir's storage changes,in order to support the decision-making in the "South-to-North water transfer project".The results showed:(1)There were significant correlations between water surface area and water level,water level and water storage,and water surface area and water storage of Danjiangkou Reservoir before and after the first operation year of the Middle Route South-to-North Water Transfer Project.Moreover,these three pairs of variables presented strong linear,conic,and cubic curve relationships respectively,with the determination coefficients of curve-fitting equations reaching 0.976,0.999,and 0.980 respectively.Therefore,one known variable of the three can be used to predict the other two unknown variables.(2)The water surface area during October 5,2014 to May 5,2016 varied by a maximum of 180 km2,and was an important factor that affected the surrounding environment.(3)The water storage in the first operation year reached a maximum of 20.41 billion m3 in early November 2014,while the amount of transferable water fluctuated between 1.653 billion m3 and 7.893 billion m3,remaining generally stable within the year.These ensured the water supply of the South-to-North Water Transfer Project during 2015.