基于水色遥感的香港海域黄色物质浓度反演模型

Retrieval model of colored dissolved organic matter concentration based on water color remote sensing in Hongkong Waters

研究了珠江口东岸香港海域黄色物质的光谱吸收特性,并分析光谱指数与吸收系数ag(440)之间的相关关系。采用CCD遥感数据和研究区海域数据采样点的同期实测光谱吸收系数,建立基于改进光谱指数NDSI、MRSI的黄色物质吸收系数反演模型。结果表明:MRSI模型提取的黄色物质吸收系数ag(440)与实测值之间的R2=0.8278,RMSE=0.0332,比NDSI模型的反演精度更高,且MRSI模型具有较强的区域适用性。利用2009～2011年3、8、12月CCD数据和MRSI吸收系数反演模型求得研究区海域黄色物质浓度,并探讨了黄色物质浓度在研究区海域的时空分布规律。

The spectral absorption characteristic of colored dissolved organic matter near the eastern Zhujiang Rive, Hongkong estuary was studied, moreover the correlation between the spectral index and the absorption coefficient αg （440） was analyzed in the article. CCD remote sensing data and the measured spectral absorption coefficient of the sampling points in target sea area over the same period were collected to establish the colored dissolved organic matter absorption coefficient retrieval model based on the modified spectral in- dex NDSI and MRSI. The results showed that the correlation coefficient between the colored dissolved organic matter absorption coeffi- cient αg （440） obtained by MRSI model and the measured one was 0. 8278, besides, RMSE = 0. 0332,which illustrated that the MR- SI model was better than the NDSI model in respect of the retrieval accuracy and the MRSI model was more necessarily applicable in regional application. At the end of the article, CCD data referring to Mar. , Aug. and Dec. records during 2009 - 2011 and the MRSI absorption coefficient retrieval model were used to get the colored dissolved organic matter concentration in target sea area, further- more, the temporal and spatial distribution of colored dissolved organic matter concentration near the eastern Zhujiang Rive, Hongkong estuary was discussed.