山东省植物源挥发性有机物排放特征

Emission Characteristics of Biogenic Volatile Organic Compounds in Shandong Province

山东省夏季主要大气污染物为臭氧(O_(3)),植物源挥发性有机物(BVOCs)作为O_(3)生成的重要前体物,其排放量的准确计算将在大气污染防治中起到重要作用.本文对山东省9个优势树种降雨前后的BVOCs排放速率和相关气象因子进行实地监测,采用G95光温模型-遥感叶生物量校正法,结合树种蓄积量信息,计算得到山东省BVOCs排放总量.结果表明:(1)山东省2021年BVOCs总排放量为256837.21 t,排放物质以异戊二烯(25.75%)和含氧VOCs(36.61%)为主,单萜烯(18.20%)、倍半萜烯(5.83%)和其他VOCs(13.61%)相对较少.(2)森林和农田是主要的BVOCs排放源,排放量占比分别为58.81%和32.07%.(3)BVOCs排放量较大的4个城市分别为临沂市(11.92%)、潍坊市(9.81%)、济南市(9.53%)和烟台市(9.09%).(4)针叶树种侧柏(Platycladus orientalis)、赤松(Pinus densiflora),阔叶树种白蜡(Fraxinus chinensis)、刺槐(Robinia pseudoacacia)、杨树(Populus tomentosa)、栎树(Quercus mongolica)、柳树(Salix babylonica)7个树种BVOCs排放速率在降雨后均显著降低,降幅在20.71%~93.94%之间.研究显示,山东省夏季BVOCs排放量较高,具有明显的季节性特征;降雨可不同程度地降低植被BVOCs排放量,夏季O_(3)污染高发期可通过人工降雨或洒水降低O_(3)前体物浓度,削减O_(3)生成.

Ozone(O_(3))is the main air pollutant in Shandong Province in summer.As an important precursor of O_(3) formation,accurate calculation of biogenic volatile organic compounds(BVOCs)emissions will play an important role in the prevention and control of air pollution.In this study,the BVOCs emission rate and related meteorological factors of 9 dominant trees in Shandong Province before and after precipitation were monitored.G95 light-temperature model-remote sensing leaf biomass correction method was used in combination with tree stock information.The total amount of BVOCs emissions in Shandong Province was calculated.The results showed that:(1)The total emission of BVOCs in Shandong Province in 2021 was 256,837.21 t,the main emissions were isoprene(25.75%)and oxygen containing VOCs(36.61%).Monoterpene(18.20%),sesquiterpene(5.83%)and other VOCs(13.61%)were relatively low.(2)Forests and farmland were the main sources of BVOCs emissions,accounting for 58.81%and 32.07%,respectively.(3)The four cities with the largest BVOCs emissions were Linyi(11.92%),Weifang(9.81%),Jinan(9.53%)and Yantai(9.09%).(4)The BVOCs emission rates of coniferous species Platycladus orientalis,Pinus densiflora,broad-leaved species(Fraxinus chinensis),Robinia pseudoacacia,poplar(Populus tomentosa),oak(Quercus Linn)and willow(Salix babylonica)decreased significantly after precipitation(20.71%-93.94%).The study shows that the BVOCs emissions in summer in Shandong Province are high,with obvious seasonal characteristics.Rainfall can reduce the vegetation BVOCs emissions to varying degrees.The concentration of O_(3) precursors can be reduced by artificial rainfall or watering in the peak period of O_(3) pollution in summer.