安徽沿江地区“1515”防线实施后植被恢复效果评价

Evaluation of Vegetation Restoration along the Yangtze River in Anhui Province After Implementation of the"1515"Defense Line

开展长江“1515”三道防线实施后的植被恢复效果研究,对评价生态修复效果具有重要的现实意义。基于2015年和2021年高分一号卫星影像数据,运用像元二分模型和转移矩阵法,分析植被覆盖度的时空变化,评价安徽沿江地区植被恢复成效。结果表明,2021年较2015年植被覆盖度整体明显提高,高覆盖度由2015年的61%增加到2021年的88%;植被覆盖度等级主要由中高覆盖度、中覆盖度向高覆盖度转移,转移面积分别为18.57%和6.31%,其中安庆和芜湖发生转移的面积最为突出;“1515”防线内,以植被中高覆盖度、中覆盖度和中低覆盖度向高覆盖度转移为主,转移面积占比由大到小的区域依次为安徽沿江1 km(27.2%、16.79%和8.06%)、5 km(24.02%、13.91%和6.01%)、15 km(22.78%、10.79%和4.35%),芜湖市在“1515”三道防线的植被恢复效果最好;植被覆盖度等级向好转移以耕地、林地、裸地为主,转移面积占比为耕地>林地>裸地,其中耕地随着防线距离的增加而转移面积减少,林地和裸地随着防线距离的增加其转移面积也相应增加。研究结果可为深入实施长江大保护战略和安徽沿江生态环境保护提供指导和参考。

For practical reasons,it was important to evaluate the effect of ecological restoration after the"1515"defense line was implemented in the Yangtze River basin.Based on GF-1 satellite imagery from 2015 and 2021,we monitored the temporal and spatial changes of vegetation coverage along the Yangtze River in Anhui province before and after the implementation of the"1515"defense line.The extent of vegetation restoration was then analyzed using the pixel binary model and the transfer matrix analysis method.The investigated area included five cities in Anhui province(Anqing,Chizhou,Tongling,Wuhu and Maanshan)and the GF-1 satellite image data for the plant growth season(May to September)were selected for analysis.The overall vegetation coverage in 2021 increased significantly compared to 2015,with the high coverage area increasing from 61%in 2015 to 88%in 2021.The vegetation coverage grades changed primarily from medium-high coverage and medium coverage to high coverage,with the respec-tive areas of the two upgraded vegetation coverages accounting for 18.57%and 6.31%.Anqing and Wuhu Cities had the largest transfer areas and the best vegetation restoration.Within the"1515"defense line,the vegetation coverage grades mainly transferred from medium-high coverage,medium coverage,medium-low coverage grades to high coverage grade,and the proportions of the transferred areas along the river from large to small were 27.2%,16.79%and 8.06%at 1 km defense line,24.02%,13.91%and 6.01%at 5 km defense line,and 22.78%,10.79%and 4.35%at 15 km defense line,respectively.The vegetation restoration of Wuhu City in the"1515"defense line was best.The transfer of the land types to better vege-tation coverage grades was dominated by cultivated land,forest land and bare land,and the proportion of the transferred area was in the order of the cultivated land>forest land>bare land.The transfer area of cultivated land decreased with increasing defense distance,and the transfer area of forest land and bare land increased with defense distance.The research results provide guidance and a reference for in-depth implementation of the Yangtze River Protection Strategy for enhancing the ecological environment along the Yangtze River in Anhui Province.