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Water Optical Properties Changes due to Land-Water Interactions in Mamiraruá Reserve, AM, Brazil

Felipe de Lucia Lobo, INPE - Instituto Nacional de Pesquisas Espaciais, (Presenting)
Conrado de Moraes Rudorff, INPE - Instituto Nacional de Pesquisas Espaciais,
Cláudio Clemente Barbosa, INPE - Instituto Nacional de Pesquisas Espaciais,
Eduardo M. Arraut, INPE - Instituto Nacional de Pesquisas Espaciais,
Evlyn M.L.M Novo, INPE - Instituto Nacional de Pesquisas Espaciais,
Helder Lima Queiroz, IDSM - Instituto de Desenvolvimento Sustentável Mamirauá,
Maria Tereza Fernandez Piedade, INPA - Instituto Nacional de Pesquisas da Amazônia,

Intense land-water interactions occur along the annual flood-pulse producing changes in the direction and velocity of water fluxes. Biogeochemical processes will differ in time and space according to the floodplain hydrology, geomorphology and biological structure. During high water the over-bank flow entering inundated forest will tend to create conditions for the suspended sediments deposition. The water also becomes enriched with dissolved organic matter (DOM) derived from the decomposition of high loads of detritus from the forest. These effects will also trigger other biochemical processes, which result in modifications of water physical-chemical properties. The optical properties will also be significantly altered, once suspended inorganic matter (SIM) scatters radiance mainly towards 550nm and DOM absorbs radiance towards the lower wavelengths in the visible range of the electromagnetic spectrum. We used Landsat/ETM+ images acquired during high water in September 2002 to map 5 classes of water, over lotic and lentic systems in the Mamirauá Reserve for Sustainable Development. Bands from the visible spectral range ETM1, 2 and 3 were used for an unsupervised classification. Water transparency (Secchi depth) samples measured in September 2006 were spatially interpolated by the weighted average method. The result from digital classification and spatial analysis of water transparency were compared. Further analysis with data expressing water fluxes, bathymetry and vegetation structure are being carried out in order to build a database for hydrodynamic modeling.

Science Theme:  ND (Nutrient Dynamics)

Presentation Type:  Poster

Abstract ID: 58

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