Abiotic features of a river from the Upper Tietê River Basin (SP, Brazil) along an environmental gradient

Abstract

Aim:This study aimed to assess the spatial and seasonal variation of the water quality and physical habitat characteristics along the upper-middle stretch of the Paraitinga River, a tributary of Tietê River, considering the potential influence of different riparian conditions along the stretch studied. Methods: Sixteen sites with different riparian vegetation, including native forest, secondary forest, pasture, and eucalyptus were sampled during the dry and rainy seasons of 2004/2005, before the damming of the Paraitinga Reservoir. Several physicochemical and habitat parameters were determined and data analyzed in relation to spatial distribution and potential influence of riparian conditions. Results: Water quality parameters were in general within the limits established by CONAMA for Class 2 waters, except for turbidity and total phosphorus. There were seasonal and spatial differences in the limnological parameters along the stretch studied and apparently they were related to point specific influences associated with land use and canopy cover. Habitat characteristics were markedly different between the upper and middle river stretches, especially in relation to depth, width, substrate and canopy cover. Conclusions: Although a direct influence on the observed variables could not be attributed solely to the riparian vegetation, vegetation cover seemed to affect particular stream characteristics. Open pasture and eucalyptus sites were subject to point specific effects that caused phosphorus inputs and higher turbidity and temperature, and showed different morphological features, suggesting that land use at the sub-watershed scale was an important factor affecting stream conditions. Keywords: Paraitinga River; riparian vegetation; longitudinal variation; limnology.Resumo: Objetivo: Este estudo teve como objetivo avaliar a variação espacial e temporal da qualidade da água e as características físicas dos habitats ao longo do trecho médio e alto do Rio Paraitinga, um tributário do Rio Tietê, considerando a possível influência de diferentes condições ripárias ao longo do trecho estudado. Métodos: Foram amostrados dezesseis locais sob diferentes condições ripárias, incluindo floresta nativa, floresta secundária, pasto e eucalipto, durante a estação seca e chuvosa de 2004/2005, previamente ao represamento do reservatório de Paraitinga. Vários parâmetros físicos e químicos da água e do habitat foram registrados e os dados analisados em relação à distribuição espacial e potencial influência das diferentes condições ripárias. Resultados: Os parâmetros de qualidade da água estiveram, em geral, dentro dos limites estabelecidos pelo CONAMA para águas de Classe 2, com exceção de turbidez e fósforo total. Diferenças sazonais e espaciais foram observadas nos parâmetros limnológicos ao longo do trecho estudado, que foram relacionadas à influências pontuais associadas ao uso do solo e à cobertura vegetal. Características do habitat diferiram entre os trechos médio e superior do rio, especialmente em relação à profundida...

Water quality change of rivers during rainy events in a watershed with different land uses in Southern Brazil

“…The study by Esteves, Lôbo and Hilsdorf (2015) in a humid area in Brazil showed that the condition of the river is affected by land use within a sub-watershed. The average turbidity found in areas of native or secondary forest was 16.27 and 14.60 NTU, respectively.…”

The influence of environmental variables in the reproductive performance of Macrobrachium amazonicum (Heller, 1862) (Caridea: Palaemonidae) females in a continental population

“…The Tietê River, along its course, suffers various impacts such as pollution, loss of riparian vegetation, and presence of dams, built mainly for electrical energy generation (Smith et al 2014). These numerous consecutive dams create a group of reservoirs that receive and accumulate organic and inorganic matter from adjacent systems, with pulses of nutrients concentration in rainy seasons, probably due to runoff (Rodgher et al 2005, Smith et al 2014, Esteves et al 2015. The clutch size of Macrobrachium species is influenced by temporary environmental factors (Mashiko 1990).…”

Freshwater quality of a stream in agricultural area where organic compost from animal and vegetable wastes is used

“…The levels of DRP in C3 exceeded up to 10 times the limit of 0.02 mg L -1 . In the evaluation of spatial and temporal variation of water quality along the Paraitinga River, a tributary of the Tietê River at São Paulo State (Brazil), the highest concentrations of TP (of the order of 0.1 mg L -1 ) were observed in the rainy season at pasture regions (Esteves;Lôbo;Hilsdorf, 2015). However, in the present work, the year in which C3 and C4 were carried out (2014) presented an atypical and very dry climate (Figure 2).…”