Ammonia, nitrite, nitrate, and orthophosphate of the Salto Grande Stream Microbasin : 22º 09’ S and 48º 19’ W, Dourado, SP, Brazil

Abstract

As part of a large research program that involves the study of biotic and abiotic parameters as periphyton, bacteria and fungi communities, organic pollution (domestic and cattle farming effluent), physiography of the drainage basin and climate data, this is the third of a series of 13 papers concerning physical and chemical water quality of Salto Grande Stream. Sampling took place from April/1985 to March/1988. Results show that nitrogen and phosphorus ranged between zero and 3.7, median 0.3 mg/L N-NH₄, zero and 57, median 2 µg/L N-NO₂, zero and 8.48, median 0.67 mg/L N-NO₃, and zero and 986, median 87 µg/L P-PO₄. An increase of the ammonia, nitrite, and phosphate concentration was verified in the rainy-warm season, and of nitrite in the dry-cold one. In some stretches of the stream, however, this seasonal behavior was not observed.