基于多时相卫星数据的太湖蓝藻暴发的动态变化监测

目的 利用遥感与地理信息系统技术监测太湖蓝藻的动态变化.方法 在对多时相的遥感数据进行几何校正与辐射校正的基础上,计算近红外与红波段的相对反射率之比,通过非监督分类处理得到分类图像,反复与假彩色图像对比分析,确定蓝藻的分类.结果 2007年3月28日太湖面积为2 302 km2,蓝藻面积为25.59km2;4月23日(部分太湖)的蓝藻面积为152.34 km2;5月20日的蓝藻面积为272 km2.结论 根据多时相的遥感数据,可快速地进行蓝藻的动态变化监测.

Dynamic change monitoring of cyanobacterial blooms using multi-temporal satellite data in Lake Taihu

Objective To monitor dynamic changes of cyanobacterial blooms using remote sensing and GIS techniques. Methods We computed the ratio of the relative reflectance between near-infrared band and red band on the basis of geometric correction and radiometric correction for multi-temporal remote sensing data, then got the classification images by unsupervised classification methods, contrasted and analyzed the images with the false color composite images to evaluate and test the accuracy of the classification, and determined the cyanobacteria. Results The area of Lake Taihu was 2 302 km2.The area of cyanobacteria was 25.59 km2 on March 28 2007, 152.34 km2 on April 23 2007 and 272 km2 on May 20 2007, respectively. Conclusions The changes of cyanobacterial blooms can be monitored quickly using multi-temporal remote sensing data.