Efektivitas Penurunan Kadar BOD Air Lindi TPA Pakusari Menggunakan Fitoremediasi Tanaman Kayu Apu (Pistia stratiotes)

Abstract

Leachate is a liquid waste generated from the decomposition of municipal solid waste and contains high concentrations of organic matter, which may cause environmental pollution if discharged without proper treatment. One environmentally friendly alternative for treating leachate is phytoremediation using water lettuce (Pistia stratiotes). This study aimed to evaluate the effectiveness of Pistia stratiotes in reducing the Biological Oxygen Demand (BOD) of leachate collected from the Pakusari Landfill and to examine the effects of plant biomass and leachate concentration on BOD removal efficiency. The experiment was conducted using a batch system for 21 days with two leachate concentrations (75% and 100%) and two plant biomass levels (125 gr and 150 gr). Leachate samples were collected on days 7, 14, and 21, while BOD analysis was performed according to SNI 6989.72:2009. The experimental data were analyzed using quadratic polynomial regression. The results showed that BOD removal was more effective at the 100% leachate concentration than at the 75% concentration. The highest removal efficiency of 51.20% was achieved by the treatment containing 150 gr of Pistia stratiotes at 100% leachate concentration on day 14. On day 21, most treatments exhibited a decline in removal efficiency, with some showing negative efficiency values, indicating an increase in BOD concentration compared to the initial condition. This phenomenon was likely associated with plant tissue decomposition, the accumulation of organic matter, and the reduced phytoremediation capacity of the plants over prolonged exposure. The quadratic polynomial regression models produced coefficients of determination (R²) ranging from 0.943 to 0.996, with p-values < 0.05, indicating that phytoremediation time had a significant effect on changes in BOD concentration. Overall, the findings demonstrate that Pistia stratiotes has considerable potential as an environmentally friendly phytoremediation agent for reducing BOD levels in leachate from the Pakusari Landfill.