基于Sentinel-2影像的火烧迹地生态指数提取及植被恢复影响评价--以浑南区棋盘山为例

Extraction of Burned Land Ecological Index and Impact Assessment of Vegetation Restoration Based on Sentinel-2 Images--Taking the Qipan MountainArea in Hunnan District as an Example

火灾对生态环境的损害是最明显最直接的,对火灾地区生态环境质量变化及灾后植被恢复的研究具有重要意义。以沈阳市棋盘山附近2019年火灾形成的火烧迹地为研究对象,基于Sentinel-2遥感影像,对比分析dNBR、NDVI、EVI、BAI、BADI 5种植被指数对火烧迹地的提取能力,筛选出最佳指数;依据遥感生态指数RSEI,综合考虑火灾对生态环境质量的短期影响;同时运用归一化植被指数NDVI和林分恢复指数SRI观察植被恢复情况。结果表明:BADI指数结合Sentinel-2数据提取火烧迹地面积最优,与官方数据相符;火灾对生态环境破坏程度严重,灾后3年RSEI呈现先快后慢的上升趋势;NDVI与SRI呈现轻度火烧迹地恢复速度最快,重度、中度火烧迹地稳步恢复的趋势。

The damage of fires to the ecological environment is the most obvious and direct,and the study of changes in the ecological environment quality in fire areas is of great significance.Based on Sentinel-2 remote sensing images,a comparative analysis was conducted on the extraction ability of dNBR,NDVI,EVI,BAI,and BADI vegetation indices on the burning site formed by the 2019 fire near Qipan Mountain in Shenyang City,and the best index was selected;Based on the remote sensing ecological index RSEI,the short-term impact of fires on ecological environment quality is comprehensively considered;the normalized vegetation index NDVI and stand restoration index SRI are simultaneously used to observe vegetation restoration.Research has shown that the combination of the BADI index and Sentinel-2 data is the best way to extract the area of burned areas,which is consistent with official data;The degree of damage caused by fires to the ecological environment is severe,and the RSEI shows an upward trend of first fast and then slow in the three years after the disaster;NDVI and SRI show the fastest recovery rate in mild burned areas,while there is a steady recovery trend in severe and moderate burned areas.