基于Sentinel-1A的2016年长江中下游重灾区洪水遥感监测及灾情评估

Flood Remote Sensing Monitoring and Disaster Assessmenton in Heavy Disaster Area of the Middle and Lower Reaches of Yangtze River in 2016 Based on Sentinel-1A Imagery

基于Sentinel-1A雷达成像系统,对2016年5月18日—8月10日长江中下游流域洪水灾害最为严重的区域(115°~117°E,28°~31°N)的整个洪水周期进行了时序动态监测,掌握整个流域的洪水水情状况,并快速提取了洪水淹没范围,对受灾地区的灾情进行评估。据监测结果,整个研究区受灾面积总计达2 096.95 km2,受灾最为严重的区域位于大型湖泊、水库周围地势相对平坦低洼的区域;在各县级行政单元中,安徽省南部的县城受灾最为严重,宿松县受淹面积最大,达290.09 km2,占全县面积的12.12%;在各地表覆被类型中,耕地和居民地受洪水灾害影响最大,占总受淹面积的80.33%,受淹耕地总计947.45 km2,受灾居民地总计76.06 km2,其中,旱地受洪灾影响最严重的区域位于安徽省怀宁县(150.95 km2),占所有受灾旱地面积的22.55%,水田受洪灾影响最为严重的县为安徽省宿松县(90.58 km2),占所有受灾水田面积的32.57%;居民地受洪灾影响最为严重的为安徽省怀宁县(12.85 km2),占所有受灾居民地总面积的16.89%。

Based on the Sentinel-1A radar imaging system,the flood period in the hardest-hit region of the middle and lower reaches of Yangtze river(115°-117°E,28°-31°N)between the May 18 to August 10 of 2016 was divided into accumulating period,flooding and stabilizing period,the temporal dynamic monitoring was observed and the inundated areas of different phases was obtained quickly,which would help to understand the process of flooding condition comprehensively.The results indicated that,from May 18 to August 10,the sum of inundated areas in the study was 2 096.95 km 2 and low-lying regions around the large lakes and rivers were submerged seriously.Among the country-level administrative units,the heaviest hit region was the southern area of Anhui Province and the serious country was Susong with the damage area of 290.09 km 2.In terms of the cover types,the most serious types were cultivated lands and the inhabited area which accounted for 80.33%of the whole inundated areas,the sum of the inundated cultivated lands and the inhabited area were respectively 947.45 km 2 and 76.06 km 2.The most serious hit region of dry lands was the country of Huaining in Anhui Province,its inundated areas was 150.95 km 2 which accounted for 22.55%of the whole inundated dry land;The most serious hit region of paddy field was the country of Susong in Anhui Province,its inundated areas was 90.58 km 2.The inhabited area of Huaining in Anhui Province accounted for 16.89%of the whole inundated paddy field.