DETERMINATION OF TOTAL NITROGEN AND CRUDE PROTEIN IN EICHHORNIA CRASSIPES PRESENTS IN RIVER APODI / MOSSORó - RN.

The aquatic macrophytes absorbs from the environment a large amount of nutrients, whether essential or not to its development. The objective of this study was to determine the amount of total nitrogen [EMBRAPA, 1999] and crude protein [Boyd, 1970] present in aquatic macrophytes of species Eichhornia crassipes linking the values obtained with the temporal variability. According to the results of leaf area (23.17; 67.21; 88.59 e 100.29 cm2), total nitrogen (4.4088; 3.1649; 2.1241 e 1.5256 g/100g) and crude protein (27.5549; 19.7805; 13.2755 e 9.5351 g/100g), can be concluded that the total nitrogen levels and crude protein decrease or remain constant with the growing of the plant. Thus, the smaller plants have higher concentrations of these nutrients.