Effectiveness of leachate disposal by the young willow sprouts Salix amygdalina.

The lysimeter experiment was conducted at the laboratory scale. Different water and leachate dilutions (0%, 25%, 50%, 100% of leachate) were supplied to the lysimeters to achieve the variation in pollutants concentration. The measure of leachate disposal effectiveness was the amount of evaporated leachate solution in evapotranspiration and transpiration. Analysis of evaporation dynamics and the impact of the plants on the leachate disposal effectiveness were determined. Correlation between biomass increase, transpiration and leachate concentration was observed. The highest evapotranspiration was obtained in the lysimeter with leachate concentration 25% and was on the level of 2.3 mm/day and for transpiration, 2.21 mm/day. The lowest values of evapotranspiration (0.55 mm/day) and transpiration (0.39 mm/day) were observed in the lysimeters supplied only by concentrated leachate. The highest leachate treatment efficiency 0.78 mm leachate/day was achieved in lysimeter K3-50% leachate concentration. There was an increase in transpiration participation in evapotranspiration in time. In the lysimeters supplied by the solutions with leachate concentrations, 25% and 50% transpiration participation in evapotranspiration ranged from 80% to 90%, in case of concentrated leachate from 60% to 70%. Evapotranspiration in all lysimeters was 3, 5-14 times higher than evaporation. It seems to be the result of plant impact on evaporation and confirms the possibility of this method being used for leachate treatment. Willows in lysimeter (K3-50% of leachate) had the most effective physiological fit to landfill leachate treatment.