Jardins flutuantes e a variação de fósforo total em açudes urbanos eutrofizados.

Abstract

Water is one of the most important assets for the maintenance of life on the planet and its volume is constant, but with increasing population, its consumption and degradation are accentuated. Thus, it is necessary the rational use of water, encouraging the preservation of water bodies and the use of tools for treatment. In urban centers, weirs are contaminated by domestic and industrial sewage, making drinking water impossible, causing bad smell, disease vectors, among others. These releases contain minerals, among them, phosphorus, which favors the reproduction of algae and the increase of this living being is responsible for the eutrophication of water bodies. An economical and efficient solution for the recovery of these dams is the use of phytoremediation systems, such as floating gardens. This work evaluates the structural and remedial performance of gardens, based on the concentrations of chlorophyll-a and total phosphorus indicators. The work was divided into three stages, with a gradual increase in the coverage area of the gardens. The gardens were initially made of bamboo, but difficulties in assembling and floating were observed, and they had to be replaced by pallet gardens with pet bottles. The efficiency of these gardens was proven by decreasing the concentrations of total phosphorus and chlorophyll-a indicators. The last stage presented an average phosphorus of 5.1 mg / L, higher than the last collection of 4.7 mg / L, while chlorophyll-a had its indicator starting at 432 μg / L and ending at 414 μg. / L. Both indicators show concentration reductions that consequently cause improvement of the water body.