Retrieval of Suspended Particulate Matter and Chlorophyll-a Concentration in a Highly Turbid Tropical River by in Situ Bio-Optical Data - A Case Study

利用實測生光資料於混濁河及河口反求懸浮顆粒及葉綠素濃度的個案研究

林依依(I-I Lin) ； 溫良碩(Saw-Wen Liang) ； 劉振榮(G. R. Liu) ； 劉康克(K. K. Liu)

《航測及遙測學刊》 7卷3期 (2002/09) Pp. 75-85

https://doi.org/10.6574/JPRS.2002.7(3).4

摘要

本研究收集了淡水河區實測水面水色光譜及水質資料，並對已定義之數個遙測水色波段對淡水河懸浮顆粒及葉綠素濃度反求之準確性質做比較。對懸浮顆料而言，520nm及625nm為測試波段。由我們分析發現， 625nm波段較為適用。而目前在軌道上之水色衛星（如SeaWiFS及MODIS）。並未配備此一波段。只有2002年剛昇空之ENVISAT-MERIS水色儀配有此一波段。對葉綠素而言，以443nm和490nm波段比較，並發現在非常混濁（既懸浮顆粒濃度高，如淡水河）之情況下，490nm波段比430nm波段對葉綠素濃度的反求有較佳的表現。

並列摘要

In situ reflectance spectra and water quality data (Chlorophyll-a, Suspended Particulate Matter, temperature, and salinity) in different parts of a highly turbid tropical river were collected. Performance of typical remote sensing ocean colour bands for retrieval of SPM (Suspended Particulate Matter) and Chl-a (Chlorophyll-a) were examined. For suspended particulate matter retrieval, 520nm and 625nm bands were tested. It was found that 625nm band performs better than the 520nm band. As none of the current ocean colour satellites (e.g. MODIS, and SEAWIFS) are equipped with the 625nm bands, this result supports the importance of the 2 upcoming ocean colour satellites (ENVISAT-MERIS and ADEOS 2-GLI), both equipping with 625nm band, for SPM retrieval in a highly turbid condition. Chlorophyll-a retrieval was examined at the 2 typical Chlorophyll-a retrieval bands, 443nm, and 490nm. Almost no correlation (correlation coefficient~0.00) were found between 443nm/555nm band ratio and Chl-a concentration. In contrary, though under highly turbid (SPM 4-25mg/l) environment, reasonably good correlation (0.83) is found between 490nm/555nm band ratio and Chl-a concentration (0-3.3ug/l). This result suggests that 490nm band is capable to reasonably retrieve Chl-a concentration up to around 3.3 ug/l even in a highly turbid tropical coastal river.