Eficacia de dos especies de macrofitas fitorremediadoras (eichornia crassipes –buchón de agua y lemna minor –lenteja de agua) en bioensayos con aguas residuales del Lago Balmoral Urbano, Villavicencio

Abstract

The deficit of clean water sources due to the presence of contaminants in the water is an environmental problem not only at the local level, but also at the regional and national level in Colombia. To counteract this problem, different water treatment systems have been implemented, including phytoremediation. The intention of this study was to evaluate the phytoremediation capacity of two species of aquatic plants – Eichornia crassipes and Lemna minor – to remove two contaminants –ammoniacal nitrogen N-NH3 and total iron Fe – from Balmoral Lake wastewater, product of agroforestry and livestock activity in neighboring areas. From residual water samples, 2 bioassays were set up, one with 100 g of E. crassipes and the other with 20 g of L. minor, and measurements of the two contaminants were made every 4-5 days for a period of 1 month. Additionally, the degree of absorption of the 2 contaminants from the root of E. crassipes and leaves of L. minor was established by maceration of the plant parts at the beginning and at the end of the bioassays. The results obtained highlight in Eichornia crassipes its capacity for absorption and accumulation of pollutants (56.5% of N-NH3 and 47.1% of total Fe), and its high reduction and removal in wastewater (95% of N-NH3 and 75.9% Total Fe). On the contrary, Lemna minor was not in this study an efficient plant in the reduction and removal of pollutants from wastewater (0.45% of N-NH3 and 45% of total Fe), with low bioaccumulation capacity (26.7% of N- NH3 and 11.3% of total Fe). The high phytoremediation capacity of E. crassipes is outstanding, which is similar to that reported in other studies. Some recommendations are made for the implementation of a phytoremediation system with aquatic macrophytes in Lake Balmoral.