【摘要】 有效地提取蓝藻水华信息对分析蓝藻动态分布有重要意义,而卫星遥感技术是进行太湖水质监测与保护的措施之一。本文以2007年7月25日Terra/MODIS数据为主要数据源,用比值植被指数(Irv)、归一化植被指数(Indv)和增强型植被指数(Iev),研究提取太湖蓝藻信息。结果表明:植被指数可以有效提取遥感影像中的蓝藻水华信息,其中Indv是应用效果较好的植被指数之一;在掩膜处理后,用Indv提取了太湖蓝藻的面积分布信息,效果较好;此外,选取Indv为测试变量,利用决策树分类法,有效地把蓝藻水华高浓度覆盖区、中浓度覆盖区和轻浓度覆盖区分开来,为准确掌握太湖蓝藻发生、发展趋势和发生程度提供可靠信息。更多还原

【Abstract】 It is very important to extract the information of cyanobacteria bloom-forming in order to analyze the distribution of cyanobacteria bloom,and remote sensing is one of measures of monitoring and protecting water quality in Lake Tai.In this paper,Terra/MODIS data of July 25,2007 were selected as a main data source.The information of cyanobacteria bloom was extracted by three kinds of MODIS vegetation index(Irv,Indv and Iev).The results showed that these vegetation index methods were able to get cyanobacteria information from the image,and that Indv is one of the methods which have better application effect.The area information of cyanobacteria bloom was also extracted by Indv after mask treatment.Then the areas covered by high,middle or low of cyanobacteria bloom was able to be separated by building decision tree with Indv as the test variable.Therefore,the present study provides technical reference for long-term monitoring cyanobacteria bloom-forming in Lake Tai.更多还原