不同类型生物滞留设施温室气体排放特征研究

Study on the characteristics of greenhouse gas emissions from different types of bioretention facilities

  • 摘要: 生物滞留设施是应用较广泛的绿色雨水基础设施之一,已有研究主要聚焦于其对雨水径流水量、水质的控制,而关于其二氧化碳(CO2)、甲烷(CH4)、氧化亚氮(N2O)等温室气体排放特征尚缺乏系统研究。针对上述问题,采用实验室柱状模拟实验的方法,人工配置雨水模拟城市道路雨水径流水量水质,以普通绿地作为参照,研究了传统生物滞留、倒置生物滞留与无植物生物滞留设施的温室气体排放特征和碳减排效果。结果表明:不同类型生物滞留设施的温室气体排放特征存在明显差异。其中,倒置生物滞留设施的CO2、N2O平均排放通量均较低,分别为66.18 mg/(m2·h)、2.98 μg/(m2·h),显著低于传统生物滞留和无植物生物滞留设施。倒置生物滞留设施的温室气体累积排放量总量最低,全球增温潜势为224.18 kg/hm2,较其他类型设施具有明显的碳减排优势,其在场次降雨事件中可减少CO2排放量0.40 kg,表明其在降低温室气体排放方面具有较大的潜力。实际工程应用中可优先选择倒置生物滞留设施,从而有效减少温室气体的排放通量。研究结果可为“双碳”背景下的生物滞留设施优化设计提供支撑。

     

    Abstract: Bioretention facilities are one of the most widely used green stormwater infrastructures. Literature reviews have mainly focused on the control of stormwater runoff quantity and quality, while there is still a gap of systematic research on the emission characteristics of greenhouse gases (GHGs) such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). To address the above issues, we conducted laboratory column simulation experiments to artificially simulate the quantity and quality of stormwater runoff from urban roads. Compared with the conventional green spaces, we investigated the GHG emission characteristics and carbon reduction effects of three different bioretention structures, namely, traditional bioretention, inverted bioretention, and plant-free bioretention. The experiment results showed that there were significant differences in GHG emission characteristics among different types of bioretention facilities. Among them, the average emission fluxes of CO2 and N2O from the inverted bioretention facility were 66.18 mg/(m2·h) and 2.98 μg/(m2·h), respectively, which were significantly lower than those of traditional bioretention and plant-free bioretention facilities. The inverted bioretention facility exhibited the lowest total cumulative emission of GHGs, with a global warming potential of 224.18 kg/hm2, demonstrating a significant carbon reduction advantage over other types of facilities. Specifically, the inverted bioretention facility could reduce CO2 emissions by 0.40 kg in a single rainfall event, demonstrating its great potential in mitigating GHG emissions. Therefore, the inverted bioretention facility could be preferentially selected for practical engineering applications to effectively reduce GHG emission fluxes. The research findings can support the optimized design of bioretention facilities under the "dual carbon" context.

     

/

返回文章
返回