Capacidade extratora de diferentes espécies vegetais cultivadas em sistemas alagados utilizados no tratamento de águas residuárias da suinocultura

Abstract

The objective of this study was to evaluate the extracting capacity of different plant species when cultivated in constructed wetlands systems (CWS) for the treatment of pig wastewaters (PW). For this, four CWS were constructed with 24.0 m x 1.1 m x 0.7 m, sealed with geomembrana of polyvinyl chloride (PVC) and filled with 0.4 m of gravel “zero”. In CWS1, CWS2 and CWS3 were planted cattail (Typha latifolia L.), Alternanthera philoxeroides (Mart.) Griseb. and grass-Tifton 85 (Cynodon dactylon Pers.), respectively. In CWS4 was planted Alternanthera on the 1st third, Typha in 2nd third and tifton-85 in the 3rd third of the bed. After passing through a organic filter filled with crushed sugar cane bagasse, the ARS was applied in SACS in a flow of 0.8 m3 d-1, which provided a detention time of 4.8 days. There was a trend to obtain higher extraction of pollutants by plants grown at the beginning of the CWS. The Alternanthera plant species that was presented greater capacity for nutrient extractor, extracting 9.5 and 23% of all total-N and K applied through ARS. Plants extracted small amounts of copper from the ARS. Because of the improved performance of plants, Alternanthera or Tifton-85 grass must be cultivated in CWS for the ARS treatment.