WATER TEMPERATURE DIAGNOSIS OF THE MOST IMPORTANT BLUMENAU STREAMS

Abstract

From June 2000 to August 2002, a study of thermal analysis of the main streams in the city of Blumenau, Santa Catarina State, South of Brazil, was carried out. Considering the water temperature as an index defining the water quality, a general diagnosis of the probable effects from ambience and antropics factors about this parameter was accomplished. Among the environmental factors connected with surface water temperature, the following factors were studied: insolation, vegetal cover and riparian zone, thermal pollution, environment temperature, direction and intensity of wind, geothermic, topographic and drained geological substrate aspects. The temperature of water and air in preestablished locations was measured. Due to the extension of the streams, it was defined from two to four sample sites for each stream. The results of the temperatures obtained in the research were matched with other environmental variables of the area. This diagnosis showed that the thermal answer of the streams is a function of the situation of the environment as well as its preservation. It has also been demonstrated that the thermal profile of a stream is an important tool in monitoring the quality of surface waters. It is a low price option, which does no require sophisticated equipments. Besides it, is relatively easy to be implemented in the water quality control works.