HJ-1A/B的FLAASH大气校正及对东湖蓝藻监测效果分析  

The Atmospheric Correction of HJ1-A/B Images and the Effects in Remote Sensing Dynamic Monitoring of Cyanobacteria Bloom in East Lake

作　　者：马鸿旭[1] 郭生练[1] 洪兴骏[1] 周研来[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072

出　　处：《中国农村水利水电》2015年第9期73-76,共4页China Rural Water and Hydropower

摘　　要：环境一号卫星(HJ1-1A/B)提供免费的高空间、高时间分辨率的遥感图像,是用于蓝藻监测的重要数据。然而,HJ-1A/B卫星由于地球大气及太阳辐射的影响会导致信号失真。为了提高绿藻监测的精度,大气纠正就变得极其重要。使用FLAASH大气校正模型对HJ-1A/B数据进行大气纠正,考虑了一定波长范围内量子效应的影像,引入了波谱响应函数进行校正。然后对纠正前后的NDVI指数进行对比,标准差由校正前的0.13提升到校正后的0.158,提升了21.5%。结果表明,FLAASH大气校正模型对HJ-1A/B数据有极好的校正效果。最后,利用NDVI数据对东湖蓝藻进行监测,进一步证明,使用FLAASH大气校正模型纠正后的数据可以更加精确地识别蓝藻信息。HJ-1A/B satellite offers free images with high spatial and temporal resolution ,which is effective to dynamically monitor cyanobacteria bloom .However ,HJ-1A/B satellite also receives distorted signals due to the influence of atmosphere .To acquire ac‐curate information of cyanobacteria bloom ,atmospheric correction is needed .In this paper ,HJ-1A/B images are corrected atmos‐pherically by using FLAASH atmosphere correction model .Considering quantum effect within a certain wavelength range ,spectral response function is introduced into the process .Then the model is used to process HJ-1A/B images ,and the NDVI after atmospher‐ic correction is compared with that before correction .Standard deviation improves from 0 .13 to 0 .158 with 21 .5% .Results indicate that atmospheric correction has reduced the distorted signals effectively .In the end ,NDVI is used to monitor cyanobacteria bloom in Donghu Lake .The accuracy has been enhanced compared with that before correction .

关 键 词：大气校正 FLAASH 蓝藻监测 归一化植被指数 

分 类 号：X87[环境科学与工程—环境工程]