LIU Ying, BAO Anming, CHEN Xi. Measuring salinity of low salinity lake by optical remote sensing:A case study of Bosten Lake[J]. Journal of Remote Sensing, 2014,18(4):902-911.
LIU Ying, BAO Anming, CHEN Xi. Measuring salinity of low salinity lake by optical remote sensing:A case study of Bosten Lake[J]. Journal of Remote Sensing, 2014,18(4):902-911. DOI: 10.11834/jrs.20143329.
Salinity is a basic property of natural water. Therefore
assessing this property is relevant. Measuring salinity by using optical remote sensing data provides the advantages of spatial coverage and high spatiotemporal precision of currently available highresolution satellite data. Full-resolution images from a medium-resolution imaging spectrometer were used to explore the f easibility of measuring the low salinity of a lake based on ocean color data. Bosten Lake was selected as the study area for this r esearch. The study was carried out by establishing the empirical relationship between salinity and Colored Dissolved Organic M aterial( CDOM)absorption coefficients. We focused on different areas of the lake on April 27
2011 and in the whole lake for an entire year from June 2010 to June 2011
in which the day of April 27
2011 is the flood day of the Kaidu River. Salinity data were acquired by using YSI-6600 and in situ sampling and combining the data gathered by the researcher. CDOM absorption coefficients were obtained by using BEAM 4. 10. 3 software. The salinity of southwestern Bosten Lake
which is dominated by the Kaidu River
exhibits an inverse relationship with CDOM absorption coefficients; however
no significant correlation is observed. The relationships between CDOM absorption coefficients and salinity vary in space and time in Bosten Lake
which is similar to other study a reas. The salinity of Bosten Lake is lower than 3 g·L- 1
and the root mean square error of measuring salinity from a satellite in space is approximately 1. 1 practical salinity units. The errors are nearly close to the salinity value of the lake
thus denoting that they are too large for estimating the salinity of Bosten Lake by using optical remote sensing data. Thus
measuring the salinity of Bosten Lake by using optical remote sensing data is difficult. Because the considerable heterogeneities observed from the relationships between CDOM absorption coefficients and salinity at different times and areas have no significant correlation
and the error of the salinity calculated by optical remote sensing data is too large. Measuring water salinity by using optical data requires that water must possess sufficient salinity and has both salinity and CDOM gradients. Moreover
CDOM conservative mixing must also be satisfied. These conditions make monitoring the low salinity of a lake difficult.