Avaliação da qualidade da água em bacias hidrográficas com diferentes impactos antrópicos

Abstract

RESUMOA ocupação desordenada do solo sem os devidos tratos conservacionistas e as ações antrópicas indevidas provocam alterações na qualidade da água local e induzem a poluição dos recursos hídricos. Este estudo teve como objetivo avaliar a qualidade da água em bacias hidrográficas do Rio Vacacaí-Mirim com uso e ocupação do solo distintos, no município de Santa Maria, Rio Grande do Sul. The different uses of soil have caused alterations in the relations between the water quality parameters analyzed. In watersheds where agricultural areas are predominant, the influence of turbidity and suspended solids was significant due to the occurrence of erosive processes.Keywords: water quality; land use; anthropogenic activity; environmental degradation. INTRODUÇÃOQualquer um que caminhe nas margens de um rio com interferência da ação antrópica consegue ver os sinais da degradação ambiental. A bacia hidrográfica do Rio Vacacaí-Mirim é de grande importância para a cidade, pois possui sub-bacias de contribuição ao reservatório de abastecimento doméstico, responsável por 40% do abastecimento de água do município de Santa Maria, e recreação de contato primário, pois está situado nas suas margens um clube de lazer.

Spatial and seasonal variation of microphytoplankton community and the correlation with environmental parameters in a hypereutrophic tropical estuary - Maranhão - Brazil

“…The combination of high nutrient concentrations may limit the growth of phytoplankton on a short time scale (WU;CHU, 2003) and the N: P ratio has been related to the occurrence of algal blooms in coastal waters (SOUZA et al, 2014). Based on that, the nitrogen was shown to be a limiting factor for the diatoms blooms and the phosphorus was a limiting factor for the proliferation of green algae and euglenoids.…”

“…However, it does not happen spatially, once the algal bloom was potentiated by high concentrations of nutrients. The entry of nutrients can occur naturally through runoff, or through the discharge of domestic sewage (THOMAS et al, 2005;PAERL et al, 2010;SOUZA et al, 2014), and when dominants (ammonium and phosphorus) the N:P ratio is less than the Redfield ratio 16:1 (COELHO et al, 2015;SILVA et al, 2015).…”

Aquatic life protection index of an urban river Bacanga basin in northern Brazil, São Luís - MA

“…It is worth noting that urban sources are the main agent of the eutrophication process (Souza and Gastaldini, 2014). The excessive accumulation of phytoplankton in water bodies increases oxygen rates in the environment during the day due to the increase in photosynthetic activity.…”

Effect of watershed land use on water quality: a case study in Córrego da Olaria Basin, São Paulo State, Brazil

“…The water quality can be assessed by physical and chemical parameters such as pH, dissolved oxygen, temperature, electric conductivity and other parameters (Chaves and Santos, 2009;Lopes, 2011;Bateni et al, 2013;Valle Junior et al, 2014), and the values obtained from ecosystem on basis for a land use planning project and implementation of conservation practices. According to Mosca (2003), Souza and Gastaldini (2014), Giri and Qiu (2016), variations of physical and chemical parameters identify the interference of land use in water quality, expand ecological knowledge of the ecosystem and detect changes in management activities.…”