| Greenhouse (CO2, CH4 and N2O) effect caused by global warming is one of high-profile environmental issues, and municipal solid waste (MSW) landfills were the significant emission sources of greenhouse gases. First, Greenhouse gas emissions from MSW landfills were explored using the GC-static chamber method. The diurnal variations of CO2, CH4 and N2O emissions were conducted under the time frame of the four selected seasons, which typically represented the different climatic conditions during the whole year around. The measured landfill lifts or cells were selected on the variations of the landfill ages and cover soil type, with or without landfill gas recovery operation, etc, Second, the livestock wastewater incubates mineralised refuse (IMR) were designed to investigate the effects factor of CH4 oxidation capacity and the rules of N2O and CO2 emissions from MSW landfills compared with original mineralised refuse (OMR) and sandy. Lastly, the experiment investigated the characteristics and kinetics of ammonia and N2O emissions from soil and from aged refuse irrigated from landfill leachate.The main contents in this study were listed as follows:MSW landfills were significantly spatial and temporal variations due to the greatly natural heterogeneities. The diurnal and seasonal variations of CO2, CH4 and N2O fluxes in the four selected landfill sites were different from each other. There were great variations of N2O emissions among diurnal and seasonal variations with the coefficient of variation ranging from 17 to 1552%. This implies that low frequency measurement were likely to greatly over-or underestimate N2O fluxes; With the variation of particle size and environmental factors, aged refuse exhibited excellent MOP performance when compared with clay soil and sandy soil. The average values for the MOP at temperatures ranging from 4-45℃ by aged refuse were 2.34 (P<0.01) and 4.71 (P<0.05) times greater than the values observed for clay soil and sandy soil, respectively. The average values for the MOP of aged refuse at a moisture content ranging from 8-32% were 2.08 (P<0.01) and 3.15 (P<0.01) times more than those of clay soil and sandy soil, respectively; The maximum CH4 oxidation potential (MOP) of Incubated Mineralised Refuse (IMR) was 15.47μmol/g d.w./h, which is substantially higher than for either the OMR (without incubation) or the soil. Following the addition of distilled water, N2O emissions from the IMR were almost two times and one order of magnitude greater than those of the OMR(P>0.05) and Soil (P>0.05). IMR was a low-energy practice for the production of a MSW landfill bio-cover material that could help to mitigate CH4 emissions without a secondary pollution risk because of its tolerance for both environmental changes;The emissions of ammonia and N2O by the soil and aged refuse irrigated from landfill leachate fit well to first-order and zero-order models with correlation coefficiency values (R22) ranging from 0.85-0.98, respectively. The K values serving as the emission factors of N2O from the aged refuse were 5.73 (P<0.05) and 14.16 (P<0.05) times more than those of clay and sandy soil, respectively. |
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