Environmental factors affecting chlorophyll-a concentration in tropical floodplain lakes, Central Brazil.
Environ Monit Assess
; 188(11): 611, 2016 Nov.
Article
em En
| MEDLINE
| ID: mdl-27726089
Chlorophyll-a (Chl-a) has been widely used in the assessment and monitoring of aquatic environments. Local and regional factors can influence Chl-a concentrations; moreover, the connection between terrestrial and aquatic ecosystems is a major paradigm within aquatic ecology. Here, we investigate the spatial distribution of Chl-a concentrations in a tropical savannah floodplain in Central Brazil using a broad spatial data set (a 900-km north-south transect; 30 lakes). We determine the relative importance of local environmental variables (limnological and morphometric) and regional (land use) and spatial distances (spatial eigenvector) on Chl-a concentrations using partial linear regression. We evaluate the direct and indirect effects of local and regional variables on Chl-a with a path analysis. Our results indicate spatially autocorrelated patterns wherein lakes in closer proximity showed more similar levels of Chl-a than more distant lakes. Local environmental factors explained most variance in Chl-a (R 2adj = 0.28; P = 0.02); more specifically, both lake area and total nitrogen significantly (P < 0.05) explained Chl-a concentrations (direct effects). Meanwhile, regional factors neither directly nor indirectly predicted Chl-a. Thus, internal processes, such as the resuspension of sediment (which is frequent in tropical floodplains), rather than external influences, were the main factors that explained Chl-a concentrations in this study. The importance of local variables in structuring Chl-a concentration may be used to guide the conservation of the aquatic ecosystems in these tropical floodplain lakes.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Lagos
/
Clorofila
Tipo de estudo:
Prognostic_studies
País/Região como assunto:
America do sul
/
Brasil
Idioma:
En
Revista:
Environ Monit Assess
Assunto da revista:
SAUDE AMBIENTAL
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Holanda