摘要
实地测试太湖水体的反射光谱,实验室分析水样,运用相关分析法探求叶绿素、悬浮物的光谱特征波段,估测叶绿素和悬浮物含量;对比LandsatETM波段,运用不同的函数曲线对相应的波段组合进行回归拟合,建立相应的估测模型,选取精度最好的两个分别对太湖的叶绿素和悬浮物含量进行估测.结果表明:(1)对多光谱遥感而言,LandsatTM/ETM是定量获取叶绿素和悬浮物的较好的数据源,但不是最适合的数据源;(2)通过ETM3与叶绿素建立一定的函数关系来估测叶绿素含量具有较高的精度,其中利用算术组合ETM3/ETM1估测叶绿素的精度最高;(3)ETM4与悬浮物具有较高的相关度,其中利用算术组合ETM4/ETM1估测悬浮物含量的精度最高;(4)LandsatETM卫星影像中,不同尺寸的像元窗口影响水质参数的估测精度;对叶绿素估测而青,7×7或者5×5窗口比较适合,对悬浮物估测而言,一般不超过3×3.
The spectra were measured with hand-spectral instrument in Lake Taihu, and the water samples were collected in situ and analyzed in the lab. The correlations between chlorophyll-a (CHL) and total suspended matter (TSM) and the measured spectra reflectivity were analyzed, on the basis of which, CHL and TSM concentrations were estimated by using the combination of the field bands, respectively. Then by the comparison of the bands of Landsat ETM, the most practicable ones were selected, which would be validated for the estimation of CHL and TSM content by using the Landsat ETM images. Finally, lots of regression models were discussed to educe the estimation models. Two of the most precise ones were used to estimate the CHL and TSM concentrations. The conclusion are as follows: (1) Landsat TM/ETM is one of the appropriate data resources in the multi-spectral remote sensing, but it isnt the most appropriate, (2) it is more precise to estimate CHL content with the third band of ETM by some certain function. In addition, it is also better to estimate CHL content with the combination of ETM3 and ETM1, (3) the correlation between ETM4 and TSM is also very close, and the most precise band to estimate TSM is ETM4/ETM1 , (4) the image window size has an effect on the precision to estimate the water quality parameters, and 5 by 5 or 7 by 7 is more appropriate to estimate CHL content, while 3 by 3 or less is more appropriate to estimate TSM content.
出处
《湖泊科学》
EI
CAS
CSCD
北大核心
2005年第2期97-103,共7页
Journal of Lake Sciences
基金
中国科学院领域前沿项目(CXNIGLAS-A02-014)江苏省自然科学基金青年科技创新人才学术带头人项目(BK2004422)中国科学院南京地理与湖泊研究所所长基金(S220445)共同资助.
