Lohila Annalea, Laurila Tuomas, Tuovinen Juha-Pekka, Aurela Mika, Hatakka Juha, Thum Tea, Pihlatie Mari, Rinne Janne, Vesala Timo
Climate and Global Change Research, Finnish Meteorological Institute, P.O. Box 503, FI-00101 Helsinki, Finland.
Environ Sci Technol. 2007 Apr 15;41(8):2717-22. doi: 10.1021/es061631h.
Continuous and area-integrating monitoring of methane (CH4) and carbon dioxide (CO2) emissions was performed for 6 and 9 months, respectively, at a municipal landfill in Finland with the micrometeorological eddy covariance (EC) method. The mean CH4 emission from June to December was 0.53 mg m(-2) s(-1), while the CO2 emission between February and December averaged 1.78 mg m(-2) s(-1). The CH4 emissions from the summit area of the landfill, where active waste deposition was going on, were 1.7 times as high as from the slope area with a better surface cover. The variation in emissions over the source area of the measurement was high. Significant seasonal variation, linked to air and soil temperature, was only seen in the CO2 release rates. Results obtained with the EC method were comparable to those measured with closed static chambers. According to the EC measurements, the gas recovery system decreased CH4 fluxes by 69-79%. The ratio of the measured CH4 and CO2 emissions roughly indicated the route of the landfill gas emission, resembling the ratio of the gases measured in the gas wells (1.24) when the emission originated from the area with no oxidizing cover layer and being smaller when CH4 oxidation had taken place.
在芬兰的一个城市垃圾填埋场，采用微气象学涡度协方差（EC）方法分别对甲烷（CH4）和二氧化碳（CO2）排放进行了为期6个月和9个月的连续及面积积分监测。6月至12月的平均CH4排放量为0.53毫克 米-2 秒-1，而2月至12月的CO2平均排放量为1.78毫克 米-2 秒-1。正在进行活跃垃圾填埋的垃圾填埋场顶部区域的CH4排放量是表面覆盖较好的斜坡区域的1.7倍。测量源区域内的排放量变化很大。仅在CO2释放速率方面观察到与空气和土壤温度相关的显著季节变化。用EC方法获得的结果与用封闭静态箱测量的结果相当。根据EC测量，气体回收系统使CH4通量降低了69%至79%。测量的CH4和CO2排放比率大致表明了垃圾填埋气的排放途径，当排放源自没有氧化覆盖层的区域时，类似于气井中测量的气体比率（1.24），而当发生CH4氧化时该比率较小。
