Retenção do fósforo em leitos cultivados com taboa (Typha spp) e arroz (Oryza sativa, L.) no tratamento de águas residuárias.

Abstract

In this study was evaluated of phosphorus retention in stream beds cultivated with Taboa (Typha sp) and Rice (Oryza sativa, L) in constructed wetlands treating wastewater. The behavior of the two stream beds was compared during the cut of the Cattail and the Rice occurred in day 26/03/04 and the time simple in days 23, 24, 25 and 30,31 of march 2004. The experiment was lead in the Experimental Field of the School of Agricultural Engineering of the State University of Campinas, Campinas (SP). The modulate experimental consisted of two rectangular masonry stream beds with dimensions of 4,0m x 1,0m x 1,0m, having as half of support the gravel #2 (9,5 - 31,5mm), with horizontal subsurface flow of the effluent one. They had been made measured hourly interval of the 9:00h at 17:00h, the inflows and outflows of the stream beds and simultaneously collected the samples. The inflows had being variation of 8,6L.h-1 to 19,0 L.h-1 and outflows variation of 5,7 L.h-1 to 16,1 L.h-1. The results had demonstrated that mean retention phosphorus was of 86% and 42% in the stream bed cultivated with Cattail, respectively, before and after the cut, and of 26% and 29% in the stream bed cultivated with Rice.