大兴安岭4种乔木枝叶燃烧碳排放因子分析

Carbon Emission Factors Analysis of Branches and Leaves of Four Tree Species in Greater Khingan Range

为了解大兴安岭4种乔木燃烧碳排放特性,为林火碳排放的估算和区域碳平衡研究提供数据支持,文章运用室内燃烧模拟装置对落叶松、樟子松、白桦、蒙古栎的枝、叶进行不同燃烧状态下的点烧试验,并用烟气分析仪、颗粒物分析仪和元素分析仪对燃烧释放含碳气体及颗粒物中元素碳(EC)、有机碳(OC)的排放特性进行深入分析。结果表明,阴燃状态下各树种燃烧释放污染物的平均排放因子均大于明燃,而明燃状态下各树种枝的污染物排放因子均大于叶;樟子松枝、叶燃烧时PM2.5平均排放因子显著大于其他3个树种。元素碳与PM2.5排放因子的比值(EFEC/EFPM2.5)表现为明燃大于阴燃,且相同燃烧状态下枝大于叶。阴燃能促进CO、CxHy等不完全燃烧产物的排放;枝燃烧产生的EC在颗粒物中的比重普遍高于叶,而OC含量则与之相反;相同燃烧状态下叶的EFOC/EFEC值大于枝,在不同燃烧状态下EFEC与EFPM2.5呈现出显著相关性。

To understand the characteristics of carbon emission from major tree species and to provide data support for revealing the carbon emission estimation from forest fires and the regional carbon balances.The emission characteristics of carbon-contained gaseous and element carbon,organic carbon in Particulate Matters(PM)released from branches and leaves of four main trees(Larix gmelinii,Pinus sylvestris var.mongolica,Betula platyphylla and Quercus mongolica)in Greater Khingan Range under different burning conditions were analyzed by using the flue gas analyzer,particulate analyzer and elemental analyzer.The results showed that the average emission factors of released pollutants by four tree species burning under smoldering stage were greater than that of flaming stage,while the emission factors of released pollutants by branches were greater than that of leaves in the flaming stage.The average emission factor of PM2.5 from Pinus sylvestris var.mongolica burning was significant greater than the other three species.The ratio of element carbon to PM2.5 emission factor(EFEC/EFPM2.5)during flaming stage is greater than smoldering stage,while the ratio of branches were greater than that of leaves in the same burning condition.Smoldering could promote the emission of incomplete combustion products such as CO and CxHyThe EC proportion in the particulate matter produced by the branch combustion was generally higher than those in the leaves,while the content of OC was opposite.In the same burning consideration,the EFOC/EFEC value of the leaves was greater than that of the branches,while EFECshowed a significant correlation with EFPM2.5 under different combustion conditions.