59631

Distribuição espacial de sedimentos suspensos do baixo rio Madeira: experimento com dados Landsat 5/TM

Favoritar este trabalho

This paper describes an experiment carried out to assess the suitability of remote sensing for mapping the spatial distribution of suspended sediment concentration (SSC) at the lower reach of the Madeira River. For that, we have applied a Landsat 5/TM database and an empirical model previously calibrated. The experiment consisted of processing a time series composed of 5 images distributed along the hydrological year of 2011, starting in the dry period of 2010 and ending in the dry period of 2011, representing key phases of the flood-pulse. The results showed that it was possible: a) to assess time changes in SSC at the lower Madeira River along the different phases of the hydrological year using the time series of Landsat-5/TM images. b) to map the spatial distribution of the SSC, provided that the following aspects are taking into account: i) presence of scan line noise related to the poor signal-to-noise ratio provided by TM sensor, mainly in phases of low SSC; ii) presence of artifacts related to cloud shading and coverage; iii) model application limited to aquatic systems characterized by optical properties controlled by suspended inorganic solids at certain phases of the hydrological year. c) Although the model used to map SSC distribution on floodplain lakes has been calibrated using water samples from the Madeira river channel, its application to floodplain lakes provided suitable results in those phases of hydrological year during which the water entering in the floodplain is dominated by inorganic particles.