Abstract
Waste landfill sites are large emission source of methane. In landfill sites, waste is biologically degradated and landfill gas such as CH4 and CO2 are generated of anaerobic environment, but the detailed mechanisms of landfill gas emission in waste layer or in cover soil layer, especially the effect of vegetation on landfill gas emission, have not been clarified. In order to find out the effect of vegetation on landfill gas emission from a landfill site, two investigations were carried out in this study.
The column test was conducted to compare CH4 flux rate from soil surface and the flux through plants. According to the experiment, the rate of CH4 flux through plant was affected by kind of plant and soil property. The outdoor experiment was conducted by using two soil containers with vegetation and one soil container without vegetation. Through experimental period, CH4 flux of the vegetated containers was bigger than CH4 flux of the non-vegetated container. Additionally, the numerical model of the outdoor experiment was developed on the assumption that the difference of CH4 flux between the vegetated soil containers and the non-vegetated soil container is caused by CH4 emission through plants and the driving force of the emission is diffusion in plants bodies. As a result, the model explained the experimental results correctly.
