引用本文: | 谢国清,李蒙,鲁韦坤,周伟民,余凌翔,李发荣,杨树平.滇池蓝藻水华光谱特征、遥感识别及暴发气象条件.湖泊科学,2010,22(3):327-336. DOI:10.18307/2010.0304 |
| XIE Guo-qing,LI Meng,LU Wei-kun,ZHOU Wei-min,YU Lin-xiang,LI Fa-rong,YANG Shu-ping.Spectral features,remote sensing identification and breaking-out meteorological condi-tions of algal bloom in Lake Dianchi. J. Lake Sci.2010,22(3):327-336. DOI:10.18307/2010.0304 |
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摘要: |
通过研究滇池蓝藻水华在可见光、红外谱段的光谱特征,并利用假彩色合成法以及归一化植被指数(NDVI)法进行了滇池蓝藻水华信息的遥感识别和提取,进而对提取结果进行了对比分析.结果表明:假彩色合成图的绿色区域和NDVI值大于-0.1的区域,为蓝藻水华区域.-0.1≤NDVI≤0.2时,轻度水华,像元内水华覆盖度为0-30%;0.20.4时,重度水华,水华浓厚,像元内蓝藻水华覆盖度为81%-100%.同时研究了激励滇池蓝藻水华暴发的关键气象因子和指标.滇池蓝藻水华暴发的关键时期是6-9月份,影响滇池蓝藻暴发的关键因子是日照和风速.6-9月份连续4-5h的光照,且风速≤2m/s的气象条件组合极易引起蓝藻水华暴发. |
关键词: MODIS 蓝藻水华 遥感识别 气象条件 滇池 |
DOI:10.18307/2010.0304 |
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基金项目:中国气象局蓝藻水体监测预警系统(一期)项目;昆明市环境保护局项目联合资助 |
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Spectral features,remote sensing identification and breaking-out meteorological condi-tions of algal bloom in Lake Dianchi |
XIE Guo-qing1, LI Meng1, LU Wei-kun1, ZHOU Wei-min1, YU Lin-xiang1, LI Fa-rong2, YANG Shu-ping2
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1.Yunnan Agrometeorological and Satellite Remote Sensing Application Center, Kunming 650034, P. R. China;2.Kunming Environment Monitor Center, Kunming 650034, P. R. China
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Abstract: |
Based on high spectral reflectivity features of Blue-green Algal Bloom(BAB) in Lake Dianchi, by MODIS satellite re-mote sensing data, RGB;621 combined false color synthesis and Normalized Difference Vegetation Index(NDVI)method, we found that green region in false color synthesis image and the region with NDVI value>—0. 1 were just the BAB area. When—0.1,NDVI≤0. 2, slight BAB occurred, and bloom coverage in a pixel reaches 0—30%; when 0. 20.4,and bloom coverage in a pixel can be 81%—100%. From June to September is the key period for BAB breaking-out in Lake Dianchi, and the key factors to affect BAB breaking-out maybe sunshine and wind velocity. During this period, if the sunshine can last for only 4—5 hours and the wind velocity≤2m/s, it's quite easy for BAB breaking-out. |
Key words: MODIS blue-green algal bloom remote sensing recognition meteomlogical condition Lake Dianchi |