Minimizing N₂O fluxes from full-scale municipal solid waste landfill with properly selected cover soil

Municipal solid waste landfills emit nitrous oxide (N₂O) gas. Assuming that the soil cover is the primary N₂O source from landfills, this study tested, during a four-year project, the hypothesis that the proper use of chosen soils with fine texture minimizes N₂O emissions. A full-scale sanitary landfill, a full-scale bioreactor landfill and a cell planted with Nerium indicum or Festuca arundinacea Schreb, at the Hangzhou Tianziling landfill in Hangzhou City were the test sites. The N₂O emission rates from all test sites were considerably lower than those reported in the published reports. Specifically, the N₂O emission rate was dependent on soil water content and nitrate concentrations in the cover soil. The effects of leachate recirculation and irrigation were minimal. Properly chosen cover soils applied to the landfills reduced N₂O flux. © 2008 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences.