不同湿度指数在湿地分类中的对比研究  

Study on Capability of Wetness Indexes for Wetlands Classification

作　　者：邢丽玮[1,2] 牛振国[2] 张海英[2] 

机构地区：[1]首都师范大学/城市环境过程与数字模拟国家重点实验室培育基地,北京100048 [2]中国科学院遥感与数字地球研究所/遥感科学国家重点实验室,北京100101

出　　处：《地理与地理信息科学》2015年第6期35-40,46,共7页Geography and Geo-Information Science

基　　金：科技部"十二五"科技支撑项目"村镇环境监测适宜关键技术研究"(2012BAJ24B01);国家自然科学基金项目"中国湿地分布的时空变化模拟研究"(41271423)

摘　　要：为探讨不同湿度指数用于湿地信息提取的能力,选取7个常用的湿度指数(包括NDWI、MNDWI、RNDWI、EWI和缨帽变换的湿度分量等)作为指标,以达赉湖国家级自然保护区为研究区,利用2013年9月6日MODIS(MOD09Q1和MOD09A1)数据,采用支持向量机分类的方法,对研究区进行湿地与非湿地区分研究,并进行湿地亚类(沼泽、水体)的分类试验。分类结果的精度评价表明:1)湿地与非湿地区分能力最好的指数为基于缨帽变换的湿度分量TC-Wetness,制图精度达97%以上,用户精度达96%;2)对湿地亚类的分类结果表明,提取水体最好的指数为第一类湿度指数,以NDWIB4,B2为最优,提取沼泽最优的指数为缨帽变换的湿度分量(TC-Wetness),可以有效排除草地对沼泽提取的干扰。研究区分类结果总体精度最高为88.7%,但沼泽的提取精度仅为48%,说明利用遥感湿度指数一种指标难以满足湿地分类的需要,多指数结合以及地形和其他相关辅助数据的加入对提高湿地分类精度具有重要帮助。In order to explore the capabilities of different wetness indexes for wetland classification, seven wetness indexes were chosen including NDWI, MNDWI, RNDWI, EWI, Tasseled Cap Wetness Index and so on. The Dalaihu National Nature Reserve was taken as the study area. The classification is based on SVM method. The main data is MODIS data （MOD09Q1 and MOD09A1）on September 6th in 2013. The result showed that for distinguishing wetland and non-wetland, the best wetness index is the Tasseled Cap Wetness Index. The production accuracy is above 97%. The user accuracy is above 96%. The second best wetness index are NDWIB5.B2 and NDWIB6,B2. The worst wetness index are based on visible band, near-infrared and shortwave infrared bands, such as NDWIB4,B2, EWI, MNDWI and RNDWI. The classification result of the wetlands subclass showed that the best wetness index for extracting water body is NDWIB4,B2. The best wetness index for extracting marsh is the Tasseled Cap Wetness Index. It can eliminate effectively the interference of grassland in extracting marsh. The highest total accuracy is 88. 7 %, but the accuracy for extracting marsh is only 48 % with this wetness index NDWIB4,B2. So there are no good performance for wetland classification with only wetness index, other auxiliary data sources such as topography, soil data, are necessary for wetland mapping.

关 键 词：MODIS 湿地提取 湿度指数 湿地遥感 达赉湖国家级自然保护区 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置] X87[自动化与计算机技术—控制科学与工程]