基于Sentinel-2数据的红树林快速提取方法  

Rapid extraction method of mangroves by using Sentinel-2 images

作　　者：奥勇[1] 吴彦芸 张龙[1] 唐冰倩 AO Yong;WU Yanyun;ZHANG Long;TANG Bingqian(School of Land Engineering,Chang'an University,Xi'an 710054,China)

机构地区：[1]长安大学土地工程学院,西安710054

出　　处：《测绘科学》2024年第7期123-133,共11页Science of Surveying and Mapping

基　　金：国家自然科学基金-联合基金项目(U23A2061)。

摘　　要：针对红树林光谱同时包含植被和湿地信息,采用卫星遥感影像难以实现红树林快速精确提取的问题,对比分析Sentinel-2影像上红树林在红边与短波红外波段与其他典型地物的光谱曲线特征后,提出了一种用于红树林快速准确提取的新型红树林提取指数NDMI。以广西防城港市珍珠湾为研究区,将该指数与4种常用红树林提取指数进行对比,并在钦州湾、东寨港红树林保护区进行适用性评价。结果表明:NDMI可增强短波红外波段反射率同红边波段反射率间的差异性,与其他常用指数相比能更有效地将红树林同其他典型地物进行区分;采用Sentinel-2遥感数据,并结合NDMI指数可在不划分潮间带的前提下快速有效地提取红树林信息,且短波红外波段中的B12波段具有更好的提取效果,总体精度和kappa系数分别为98.6%和0.9249。该研究为红树林遥感提取提供了一种快速简便的新方法。In response to the problem that the spectrum of mangroves contains both vegetation and wetland information,it is difficult to achieve rapid and accurate extraction of mangroves using satellite remote sensing images.This paper compares and analyzes the spectral curve characteristics of mangroves in the red edge and shortwave infrared bands on Sentinel-2 images with other typical land features,and proposes a new type of mangrove extraction index NDMI(Normalized Difference Mangrove Index,NDMI)for rapid and accurate extraction of mangroves.Taking Pearl Harbour in Fangchenggang City,Guangxi as the research area,this index was compared with four commonly used mangrove extraction indices,and its applicability was evaluated in Qinzhou Harbour and Dongzhaigang East Harbour National Nature Reserve.The results show that NDMI can enhance the difference in reflectance between short-wave length infrared bands and the red-edge band,and can more effectively distinguish mangroves from other typical land features compared to other commonly used indices;By using Sentinel-2 remote sensing data and combining it with NDMI index,mangrove information can be quickly and effectively extracted without dividing the intertidal zone.Moreover,the b12 band in the short-wave length infrared bands has better extraction performance,with an overall accuracy and kappa coefficient of 98.6%and 0.9249,respectively.This study provides a fast and convenient new method for remote sensing extraction of mangroves.

关 键 词：Sentinel-2 红树林 潮间带 红树林光谱曲线特征 NDMI 

分 类 号：P237[天文地球—摄影测量与遥感]