{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:40:30Z","timestamp":1760244030068,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2009,1,23]],"date-time":"2009-01-23T00:00:00Z","timestamp":1232668800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Spectra, salinity, total suspended solids (TSS, in mg\/L) and colored dissolved organic matter (CDOM, ag(400) at 400 nm) sampled in stations in 44 different locations on December 18, 19 and 21, in 2006 were measured and analyzed. The studied field covered a large variety of optically different waters, the absorption coefficient of CDOM ([ag(400)] in m-1) varied between 0.488 and 1.41 m-1, and the TSS concentrations (mg\/L) varied between 7.0 and 241.1 mg\/L. In order to detect salinity of the Pearl River Estuary, we analyzed the spectral properties of TSS and CDOM, and the relationships between field water reflectance spectra and water constituents\u2019 concentrations based on the synchronous in-situ and satellite hyper-spectral image analysis. A good correlation was discovered (the positive correlation by linear fit), between in-situ reflectance ratio R680\/R527 and TSS concentrations (R2 = 0.65) for the salinity range of 1.74-22.12. However, the result also showed that the absorption coefficient of CDOM was not tightly correlated with reflectance. In addition, we also observed two significant relationships (R2 &gt; 0.77), one between TSS concentrations and surface salinity and the other between the absorption coefficient of CDOM and surface salinity. Finally, we develop a novel method to understand surface salinity distribution of estuarine waters from the calibrated EO-1 Hyperion reflectance data in the Pearl River Estuary, i.e. channels with high salinity and shoals with low salinity. The EO-1 Hyperion derived surface salinity and TSSconcentrations were validated using in-situ data that were collected on December 21, 2006, synchronous with EO-1 Hyperion satellite imagery acquisition. The results showed that the semi-empirical relationships are capable of predicting salinity from EO-1 Hyperion imagery in the Pearl River Estuary (RMSE &lt; 2\u2030).<\/jats:p>","DOI":"10.3390\/s90100656","type":"journal-article","created":{"date-parts":[[2009,1,23]],"date-time":"2009-01-23T11:40:49Z","timestamp":1232710849000},"page":"656-673","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Use of Reflectance Ratios as a Proxy for Coastal Water Constituent Monitoring in the Pearl River Estuary"],"prefix":"10.3390","volume":"9","author":[{"given":"Li-Gang","family":"Fang","sequence":"first","affiliation":[{"name":"Department of Computer Engineering, Suzhou Vocational University, Suzhou 215104, P.R. China"},{"name":"Public Laboratory of Environmental Science and Technology of Guangdong Province, Guangzhou Institute of Geography, Guangzhou 510070, P.R. China"},{"name":"The Water Supply Corporation of Panyu District, Guangzhou 511400, P.R. China"}]},{"given":"Shui-Sen","family":"Chen","sequence":"additional","affiliation":[{"name":"Public Laboratory of Environmental Science and Technology of Guangdong Province, Guangzhou Institute of Geography, Guangzhou 510070, P.R. China"},{"name":"The Water Supply Corporation of Panyu District, Guangzhou 511400, P.R. China"}]},{"given":"Dong","family":"Li","sequence":"additional","affiliation":[{"name":"The Water Supply Corporation of Panyu District, Guangzhou 511400, P.R. China"}]},{"given":"Hong-Li","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering, Suzhou Vocational University, Suzhou 215104, P.R. China"}]}],"member":"1968","published-online":{"date-parts":[[2009,1,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"903","DOI":"10.4319\/lo.1984.29.5.0903","article-title":"Direct and inverse irradiance models in hydrologic optics","volume":"29","author":"Preisendorfer","year":"1984","journal-title":"Limnol. Oceanogr."},{"key":"ref_2","first-page":"275","article-title":"Analysis of CDOM spatial distribution variations in Chaohu Lake and its soures by three dimensional fluorescence excitation-emission matrix","volume":"26","author":"Wang","year":"2006","journal-title":"Acta Sci. Cirum."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1809","DOI":"10.1016\/j.csr.2004.06.009","article-title":"Observations on the size and settling velocity distributions of suspended sediment in the Pearl River Estuary, China","volume":"24","author":"Xia","year":"2004","journal-title":"Cont. 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