Modeling Suspended Solids Concentrations Based on TM/LANDSAT-5 Images atGuanabara Bay, Rj, Brazil

摘要

A distribution of Total Suspended Solids (TSS) for Guanabara Bay is presented.The distribution was obtained through the expansion of a stepwise regression model that resulted from in situ and TM/LANDSAT-5 data. Water samples from 12 sites in the Bay were collected simultaneously in a TM overpass. TSS was related to nine different TM bands and band combinations through simple correlation analysis. Bands 4 (760-900 nm) and 6 (10400-12500 nm) had statistically significant correlation coefficients (r = 0.87 and 0.74 respectively), and were selected for stepwise linear regression analysis. Determination coefficients (r(exp 2)), with a 95 percent confidence level, were 0.69 for dependent variables bands 4 and 6 and 0.72 for band 4 alone. Therefore 72 percent of the TSS variability in the surface water of the Bay is explained by band 4. Based on this result a map of concentration levels for about 400 sq km of estuarine waters at the Bay region was digitally produced in an interactive multispectral image analyzer. The results show a potential application of orbital remote sensing to water quality monitoring and could provide environmental agencies with complementary continuous information for estuarine areas with few or missing water sampling points.