基于修正的GHG-RA模型的三峡库区甲烷排放通量估算

Evaluation of Methane Emission Flux of Three Gorges Reservoir Area base on Revised GHG-RA Model

利用以往研究中三峡库区的24个监测点的甲烷排放通量实测数据及其年平均气温和降水量数据,对温室气体排放风险评估模型(greenhouse gas risk assessment tool,GHG-RA)的系数进行了修正;利用修正的GHG-RA模型,估算了三峡库区24个监测点的甲烷排放通量;对2018~2117年期间三峡库区的平均甲烷排放风险进行了评价。研究结果表明,利用修正的GHG-RA模型估算的24个监测点的甲烷排放通量的平均值为0.222 mg/(m^2·h),与实测值的均方根误差和平均偏差分别为0.12 mg/(m^2·h)和0.32 mg/(m^2·h);估算的2018~2117年期间三峡库区的平均甲烷排放通量为0.255 mg/(m^2·h),甲烷排放风险为中等排放风险。

Monitoring methane emission flux on the spot requires a large amount of investment, so using models to simulate regional methane emission flux has become the main research method. In this study,measured methane emission fluxes in 24 monitoring points in the Three Gorges Reservoir area and the annual average temperature and precipitation data from the corresponding monitoring points were used to revise the coefficients of greenhouse gas risk assessment tool(GHG-RA model). The methane emission flux from every monitoring points base on revised GHG-RA model. The methane emission risk in the region during the period of 2018-2117 was evaluated. The results showed that the average methane emission flux from every monitoring points in Three Gorges Reservoir area was 0.222 mg/(m^2· h) base on revised GHGRA model. The root mean square error and average deviation of the simulated and measured values of the modified model were 0.12 mg/(m^2· h) and 0.32 mg/(m^2· h) respectively. The average methane emission flux of the Three Gorges Reservoir area was 0.255 mg/(m^2· h) base on revised GHG-RA model during the period of 2018-2117, and the gas emission risk of methane in the region was medium.