基于GEE平台的鄱阳湖区水体面积变化时空格局分析
The Spatiotemporal Pattern Analysis of Water Body Area Change in Poyang Lake Region Based on GEE Platform
刘修钰 1朱青 1王薇 1蔡永立1
作者信息
- 1. 上海交通大学设计学院中国城市治理研究院,上海,200240;自然资源部国土空间生态治理数字工程技术创新中心,上海,200240
- 折叠
摘要
利用Google Earth Engine(GEE)平台,采用基于Sentinel-1双极化水体指数(Sentinel-1 dual-polarized water index,SDWI)的Otsu最佳阈值法对鄱阳湖区进行水体范围提取,并对水体面积进行曼-肯德尔(Mann-Kendall)趋势检验,同时对2015—2022年淹没频率的空间格局变化进行统计分析.结果表明:①基于GEE平台,利用Sentinel-1数据可以实现水体面积高时相频率的动态监测,识别精度最高达到0.93;②2015—2021年鄱阳湖区水体面积整体呈显著上升趋势(Z>0,P<0.01),其中,2018年枯水年水体面积波动较2020年丰水年小;③鄱阳湖区西南及东南部分季节性水体广布,水体空间格局变化最为显著,研究时段内淹没频率为(0,20％]的面积年际变化最大.研究表明,基于GEE平台和Sentinel-1雷达数据可以有效监测鄱阳湖区的水体面积动态变化,能够为区域洪涝灾害风险管理、湿地栖息地保护提供支持.
Abstract
Leveraging the Google Earth Engine (GEE) plat-form,the Otsu optimal threshold method based on Sentinel-1 dual-polarized water index (SDWI) was used to extract the extent of water bodies in the Poyang Lake area,and the area of water bodies was analyzed by Mann-Kendall trend test,as well as statistical analysis of the spatial pattern changes of in-undation frequency from 2015 to 2022. The results show that,first,the dynamic monitoring of high temporal phase fre-quency of water body area can be realized by using Sentinel-1 data combined with GEE platform,and the recognition accu-racy reaches up to 0.93. Second,the overall water body area of Poyang Lake area shows a significant increasing trend from 2015 to 2021 (Z>0,P<0. 01),among which the fluctua-tion of water body area in 2018 dry water year is smaller than that in 2020 abundant water year. Third,seasonal water bod-ies are widely spread in southwest and southeast parts of Poy-ang Lake area,and the spatial pattern of water bodies is the most significant change,and the area with inundation frequen-cy of (0,20％]has the largest interannual variation during the study period. The study shows that based on GEE platform and Sentinel-1 radar data can effectively monitor the dynamic changes of water body area in Poyang Lake area,which can provide support for regional flood disaster risk management and wetland habitat protection.
关键词
Sentinel-1/Google/Earth/Engine/鄱阳湖区/水体面积/Sentinel-1双极化水体指数/时空变化Key words
Sentinel-1/Google Earth Engine/Poyang Lake region/water area/Sentinel-1 dual-polarized water index/spatiotemporal dynamics引用本文复制引用
基金项目
教育部哲学社科重大攻关项目(19JZD023)
出版年
2024
NETL
NSTL
万方数据