Please use this identifier to cite or link to this item:
https://repositorio.inpa.gov.br/handle/1/17476
Title: | The optical properties of river and floodplain waters in the Amazon River Basin: Implications for satellite-based measurements of suspended particulate matter |
Authors: | Martinez, Jean Michel Espinoza-Villar, Raúl Armijos, E. Silva Moreira, Luciane |
Keywords: | Absorption Coefficient Color Concentration (composition) Dissolved Organic Matter Floodplain Fluvial Deposit Granulometry In-situ Measurement Mineralogy River Water Satellite Imagery Suspended Particulate Matter Amazon Basin Amazon River |
Issue Date: | 2015 |
metadata.dc.publisher.journal: | Journal of Geophysical Research F: Earth Surface |
metadata.dc.relation.ispartof: | Volume 120, Número 7, Pags. 1274-1287 |
Abstract: | Satellite images can now be used to assess river sediment discharge, and systematic studies over rivers and lakes are required to support such applications and document the variability of inland water optical properties at the watershed scale. The optical properties of the Amazon Basin waters were analyzed from in situ measurements of the remote sensing reflectance (R<inf>rs</inf>) at 279 stations and downwelling diffuse attenuation coefficients (K<inf>d</inf>) at 133 stations. Measurements of the apparent optical properties, suspended particulate matter (SPM) contents, and characteristics and colored dissolved organic matter (CDOM) absorption spectra were performed during 16 cruises along the main Amazonian Rivers draining the Andes and for some tributaries. Surface-suspended sediment granulometry and mineralogy showed a stable distribution at the catchment scale, even over large distances and between tributaries. The particle number-size distribution was best described using a segmented distribution with a slope of 2.2 for the fine range (1-15μm), and the CDOM absorption coefficient at 440nm varied from 1.8 to 7.9m-1. Overall, both R<inf>rs</inf> and K<inf>d</inf> were strongly correlated with SPM, although strong CDOM absorption limited the use of the blue spectrum. Reflectance saturation from blue to red was observed at approximately 100gm-3, whereas the near-infrared (NIR) wavelength enabled the monitoring of the full SPM range (5-620gm-3). In contrast, K<inf>d</inf> showed no saturation for SPM from green to NIR, and a linear model was calculated. The use of the reflectance ratio was investigated and shown to improve the suspended sediment concentration retrieval performance. ©2015. American Geophysical Union. All Rights Reserved. |
metadata.dc.identifier.doi: | 10.1002/2014JF003404 |
Appears in Collections: | Artigos |
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.