Spatial changes in the water quality of Itajaí-Açú Fluvial-Estuarine System, Santa Catarina, Brazil

Abstract

This study was carried out with the aim of evaluating the spatial variation of the water quality in the Itajaí-Açú River estuary. Seven stations along the estuary were monitored on a weekly basis, from October 2003 to December 2004, plus two stations in tributaries (Itajaí-Mirim River, the main tributary, and one reference station). This monitoring included measurements of salinity, pH, dissolved oxygen, temperature, nutrients (NH , total phosphorous and dissolved organic phosphorus (TP and DOP), particulate organic carbon (POC), suspended particulate matter (SPM) and chlorophyll-a (Cla). Multivariate analyses demonstrated the compartmentalization of the system based on the deterioration in water quality and marine influence. Urban development was the main factor responsible for the spatial variation of the monitored variables, resulting in increases in the indicators for organic matter and a progressive decrease in O 2 . Despite the effect of dilution by marine influence, there was an increase in ammonium, attributed to the influence of the municipal districts of Itajaí and Navegantes, close to the river mouth.

AVALIAÇÃO DAS CONDIÇÕES AMBIENTAIS DO ESTUÁRIO DO RIO CARRAPICHO (Itamaracá-PE): BIOMASSA FITOPLANCTÔNICA E HIDROLOGIA

“…O mesmo padrão foi observado em outros estuários da região nordeste do Brasil por Losada et al (2003), no Ilhetas e Mamucabas (PE); no Ariquindá (PE), por Grego et al (2009), no estuário do rio Maracaípe (PE), por Bastos et al (2011); e no estuário do rio Caravelas (BA) por Schettini et al (2010).…”

“…Resultados compatíveis ao do presente trabalho foram observados por Losada et al (2003), nos estuários dos rios Ilheta e Mamucaba; por Grego et al (2009), no estuário do rio Arinquindá (PE); por Pereira-Filho et al (2010), no rio Itajaí-Açú (SC), e por Bastos et al (2011), no estuário do rio Maracaípe.…”

Spatiotemporal distribution of the benthic macrofauna in an urbanized subtropical estuary: environmental variations and anthropogenic impacts

“…The main sources of pollution of the river are sanitary waste, garbage and industrial wastewater mainly from textile, metallurgy and galvanoplastic industries spread around the water basin (PEREIRA-FILHO et al, 2010).…”

“…Monthly average river discharge is around 230 m 3 /s, and tide pattern is mixed semi-diurnal, with average interval of 0.8m (SCHETTINI, 2002). The Itajaí-Açu River represents 90% of the freshwater input to the estuary, draining a 15500 km² water basin (PEREIRA-FILHO et al, 2010). Climate at the low estuary can be defined as moist-subtropical, characterized by evenly distributed rainfall along the year and average air temperature above 18º C (GAPLAN, 1986).…”

Spacial and temporal characterization of water quality in the Cuiab River Basin of Central Brazil

“…Several studies have addressed the evaluation of water quality data using multivariate analysis in water bodies around the world (Brondnjak-Voncina et al, 2002;Felipe-Sotelo et al, 2007;Mendiguchía et al, 2004;Kazi et. al., 2009;Pejman et al, 2009) including Brazil (Silva and Sacomani, 2001;Zeilhofer et al, 2006;Palácio et al, 2009, Alexandre et al, 2010Pereira-Filho et al, 2010;Palácio et al, 2011). This study aimed to evaluate the water quality variables responsible for the spatial and temporal variation of water quality as well as the similarities and dissimilarities among stations on the River Cuiabá in the hydrological year 2010/2011 that could be affected by urban effluent discharge and diffuse pollution.…”