屋顶绿化二氧化碳减排效益的研究

Capacity of Green Roof on CO_2 Absorption

屋顶绿化不仅能够美化城市环境,而且对城市二氧化碳减排具有一定作用。文章利用自行设计的熏气装置对几种常见屋顶绿化植物进行CO2熏气实验,测定其对CO2的吸收速率和影响因素;实验结果表明,红叶石楠、红继木和石榴等绿化植物对CO2具有显著的吸收能力,其中红叶石楠的吸收速率最高,达7.058 L/(m.2d),绿化植物对CO2的吸收速率受屋面温度影响较大,温度超过34℃时吸收速率快速减小;在实验观测基础上,结合武汉城市区域气候特征、建筑物荷载能力、屋顶绿化可用面积等信息,分析得到武汉市进行规模化屋顶绿化之后,每年可吸收转化CO21.696×106t,相当于一个194 MW火力发电厂一年的CO2排放量,屋顶绿化的发展前景较可观。

Green roof not only can beantify the environment, but also has a certain effect on reduction of carbon dioxide emission in urban. CO2 absorption rate of some common green roof plants and its influencing factors were studied by self- designed fumigation experimental device. Results showed that Photinia fraseri, red after-wood and pomegranate have a good ability to absorb CO2, among which Photinia fraseri has the best CO2 absorption ability about 7.058 L/（m2 d）. CO2 absorption rate of green plants has more relationship with roof temperature, and the absorption rates decrease rapidly when temperature exceeds 34℃. Based on the experiment results, together with regional climate characteristics of Wuhan, load bearing capacity of the building and usable area for green roof, the capacity of green roof on CO2 emission reduction was 1.696×10^6 t/a, which was equal to CO2 emission from a thermal power plant with 194 MW in 1 year. Development prospects of capacity of green roof on CO2 absorption were investigated as well.