外来红树无瓣海桑在广东省的空间分布研究

Research on the Spatial Distribution of Exotic Sonneratia apetala in Guangdong Province

外来红树无瓣海桑Sonneratia apetala是我国红树林造林的重要树种,具有耐水浸、生长速度快、适应性强等特点。随着无瓣海桑的自然更新与扩张,其入侵风险引起社会广泛关注。为准确获取无瓣海桑分布,加强对这一外来树种的跟踪检测,研究基于Sentinel-2卫星影像和随机森林算法,在Google Earth Engine平台下构建了2015年广东省无瓣海桑分布数据,总体精度达到96.3%。结果表明:2015年广东省无瓣海桑总面积为1704.33 hm^(2)。应用核密度分析方法发现,这一外来红树主要集中在雷州半岛西部和珠江口区域。与2020年的数据对比显示,广东省无瓣海桑的斑块数量和斑块面积均有较为显著的扩张。

The exotic Sonneratia apetala plays a crucial role as an important introduced tree species for mangrove afforestation in China,characterized by its inundation tolerance,fast growth rate,and strong adaptability.With the natural regeneration and expansion of S.apetala,its invasion risk has aroused widespread concern in society.To accurately obtain the distribution of S.apetala and strengthen the tracking and detection of this exotic species,this paper,based on the Sentinel-2 satellite image and the random forest algorithm,constructs the distribution data of S.apetala in Guangdong province in 2015 under the Google Earth Engine platform,achieving an overall accuracy of 96.3%.The results revealed that the total area of S.apetala in Guangdong province was 1704.33 hm^(2)in 2015.Utilizing the kernel density estimation method,the exotic mangrove species is predominantly distributed in the western of Leizhou Peninsula and the Pearl River Estuary region.Comparison with the data from 2020 showed a significant expansion in both the number and area of patches in Guangdong province.