Hidroquímica dos rios Arienga e Murucupí, município de Barcarena (PA).

Abstract

In this study two rivers located in the Municipality of Barcarena, Para State, with the objective of assessing the hydrochemical composition of the surface waters of both, according to seasonal and tidal areas were chosen. The Murucupi River is located near the industrial center of Vila do Conde and Arienga River located farther from the industrial area and less presence of housing occupations in your surroundings. Sampling was conducted in the months of February, May, August and November 2011 in six (06) sampling points in Arienga river and seven (07) points in Murucupi river. The variables analyzed were: temperature, total dissolved solids (TDS), pH, conductivity, salinity, dissolved oxygen (DO), biochemical oxygen demand (BOD), Al, Cu, Cr, Fe, Mn, Na, Ba, Co, Zn, NO2 -, NO3-, PO4 3-, SO42-, NH3+, K+ and total hardness (as CaCO3 and MgCO3). To analyze the data and hydrochemical distribution in the waters of the rivers studied was used as a statistical tool to Multivariate Analysis, in which, through Hierarchical Cluster Analysis and Principal Components Analysis can observe the distribution of hydrochemical Arienga Murucupi and rivers in rainy and dry period. The Arienga Murucupi and rivers during the rainy season showed distinct hydrochemical characteristics in the evaluated extensions, observing higher concentrations for DO and iron Arienga river, while in Murucupi River, concentrations of pH, temperature, conductivity, TDS, salinity, BOD, ammonia, nitrite, nitrate, phosphate, sulfate, hardness, barium, copper, cobalt, potassium, manganese and sodium were higher, probably due to the intensification of leached materials from domestic sewage and industrial around this river as a result of greatest rainfall. In less rainy period observed higher values for barium, cobalt, copper, zinc and ammonia arienga river, the availability of some elements in this water body, may have occurred due to the princilpamente lower pH values recorded in this period in the stretch sampling near the springs, while the river Murucupi direct influence on the hydrochemical characteristics of these waters could be observed through the variables pH, temperature, conductivity, TDS, salinity, BOD, ammonia, nitrite, nitrate, phosphate, sulfate, hardness, barium , copper, cobalt, potassium, manganese and sodium that were in greater concentration, these results are consistent with field observations, which describe the continuous release of domestic sewage in the river Murucupi produced by the communities around it, as Village Cabanos and Laranjal Community.