基于多源数据融合的水库DEM构建方法研究  

Research on the construction method of reservoir DEM based on multi-source data fusion

作　　者：杨瑾 崔海涛[1] 肖洲 杨建英[2] 庄妍 YANG Jin;CUI Haitao;XIAO Zhou;YANG Jianying;ZHUANG Yan(Beijing Institute of Water,Beijing 100048,China;Beijing Forestry University,Beijing 100083,China;Beijing Miyun Reservoir Management Office,Beijing 101512,China)

机构地区：[1]北京市水利规划设计研究院,北京100048 [2]北京林业大学,北京100083 [3]北京市密云水库管理处,北京101512

出　　处：《测绘科学》2024年第7期184-194,共11页Science of Surveying and Mapping

基　　金：国家水体污染控制与治理科技重大专项(2018ZX07110001)。

摘　　要：针对水库水下地形获取难度大、成本高的问题,提出了一种利用长时间序列影像和水位数据构建水库数字高程模型的方法,以密云水库为研究区,基于Google earth engine云平台收集了2014—2023年370景Sentinel-1和297景Sentinel-2影像,结合SNIC分割和OSTU阈值算法进行面向对象的水体范围提取。根据影像采集当日的水位,采用K-Means方法将影像集聚类为45组,对每个分组内的水体提取结果进行合并,得到45个水位下的库容曲线。通过库容曲线提取了467601个高程点,采用创建TIN的空间插值方法构建5 m分辨率的DEM,基于DEM计算的库容与密云水库管理处观测库容基本吻合(R^(2)=0.9998),在此基础上,探究了密云水库“水位-面积-库容”关系模型和水深分布特征。结果表明,密云水库呈现“西南深、东北浅”“白河入口深、潮河入口浅”的特征,水位与面积呈强线性相关关系(R^(2)=0.9947)、水位与库容呈明显的二次多项式关系(R^(2)=1),根据建立的关系式计算面积相对误差约2%,计算库容的相对误差小于1%,可为水库的监测和管理提供有效数据。To address the challenges of difficulty and high cost in obtaining underwater terrain of reservoirs,this paper proposes a method for constructing a digital elevation model(DEM)of reservoirs using long-term time series images and water level data.Taking the Miyun Reservoir as the study area,a total of 370 scenes of Sentinel-1 and 297 scenes of Sentinel-2 images from 2014 to 2023 were collected based on the Google Earth Engine(GEE)cloud platform.The object-oriented water body extraction was conducted using the SNIC segmentation and OSTU threshold algorithm.According to the water level on the day of image acquisition,the images were clustered into 45 groups using the K-Means method,and the extraction results of water bodies in each group were merged to obtain 45 storage capacity curves corresponding to different water levels.A total of 467601 elevation points were extracted from the storage capacity curves,and a DEM with a resolution of 5 m was constructed using spatial interpolation methods based on TIN creation.The storage capacity calculated based on the DEM was in basic agreement with the observed storage capacity of the Miyun Reservoir Management Office(R^(2)=0.9998).Based on this,the relationship model of“water level-area-storage capacity”and the distribution characteristics of water depth in the Miyun Reservoir were explored.The results show that the Miyun Reservoir exhibits characteristics of“deeper in the southwest,shallower in the northeast,”and“deeper at the entrance of Baihe River,shallower at the entrance of Chaohu River.”The water level is strongly linearly correlated with the area(R^(2)=0.9947),and the water level is significantly correlated with the storage capacity in a quadratic polynomial relationship(R^(2)=1).According to the established relationship,the relative error of area calculation is approximately 2%,and the relative error of storage capacity calculation is less than 1%,which can provide effective data for reservoir monitoring and management.

关 键 词：Sentinel-1/Sentinel-2 水位 不规则三角网(TIN) DEM 密云水库 

分 类 号：P228[天文地球—大地测量学与测量工程]