Advanced search
Start date
Betweenand
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Variability in the light absorption coefficients of phytoplankton, nonalgal particles, and colored dissolved organic matter in a subtropical bay (Brazil)

Full text
Author(s):
Ferreira, Amabile [1] ; Ciotti, Aurea Maria [1] ; Colo Giannini, Maria Fernanda [1]
Total Authors: 3
Affiliation:
[1] Univ Sao Paulo, Ctr Biol Marinha CEBIMar, Lab Aquarela, BR-11600000 Sao Sebastiao, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: ESTUARINE COASTAL AND SHELF SCIENCE; v. 139, p. 127-136, FEB 20 2014.
Web of Science Citations: 5
Abstract

This study characterized the variability in magnitudes and spectral shapes of the absorption coefficients of phytoplankton, detritus, and colored dissolved organic matter (CDOM) in a dynamic bay (Santos Bay) in southeastern Brazil in response to the contributions of the main estuarine channel and large tide variations, therefore in different time scales. Two strategies were adopted: (1) monthly year-round sampling in the estuarine channel and Santos Bay and (2) sampling in Santos Bay during spring/neap tides and cold/warm months. Chlorophyll-a concentration and CDOM absorption were higher during warm (wet) months, while the relative contribution of organic and inorganic particles was driven by neap/spring tide cycles. Salinity partially accounted for changes in optical variables, especially for CDOM absorption and total suspended matter (TSM) during cold months and neap tides, respectively. The spectral shapes of detritus and CDOM absorption showed relatively little variability for the entire dataset and were not considered feasible for monitoring purposes. The spectral shape of phytoplankton absorption (index of cell size) varied broadly, with no remarkable dependence on the sampling conditions. Comparison of absorption coefficients measured by the Quantitative Filter Technique (QFT) and Transmittance Reflectance (TR) method showed higher phytoplankton coefficients toward longer visible wavelengths (flatter spectra) and shallower slopes of detritus absorption yielded by the TR method. Our results also suggest that measurements at the near red spectral region result from not only scattering signals but also non-algal particle absorption. (C) 2014 Elsevier Ltd. All rights reserved. (AU)

FAPESP's process: 03/09932-1 - Influence of the estuarine complex of the Baixada Santista on the ecosystem of the adjacent platform (ECOSAN)
Grantee:Ana Maria Setubal Pires-Vanin
Support Opportunities: PRONEX Research - Thematic Grants