基于卫星火点排放清单(FINN)的我国东北三省生物质户外燃烧网格化清单建立及时空演变特征分析

Establishment and Spatiotemporal Evolution of Biomass Outdoor Combustion Grid in Three Northeastern Provinces of China Based on Fire INventory from NCAR(FINN)

生物质户外燃烧是影响环境空气质量的重要污染源,东北三省作为我国的重要农业产区,分析其生物质户外燃烧情况能够为当地秸秆资源综合利用和环境质量改善等提供依据.该研究基于卫星火点排放清单(Fire INventory from NCAR,FINN),分析了我国东北三省2016-2020年生物质户外燃烧火点的时空分布特征,结合空气质量监测数据进行了重污染天气成因分析,并建立了可用于数值模拟的生物质户外燃烧源网格化清单.结果表明:①东北三省2018-2019年火点数量较2016-2017年大幅减少,2020年有所增加.年内火点主要出现在春秋两季,春季相对更多.火点主要分布在东北平原,即黑龙江省的东部和西部,以及吉林省西部等,其他地区火点数量相对较少,呈零散式分布的特点.②该研究搭建了东北三省2016-2020年生物质户外燃烧源网格化清单,清单空间分辨率为3km,污染物种类包括SO_(2)、NOx、CO、NMVOC、NH_(3)、PM_(10)、PM_(2.5)、BC和OC等,2016-2020年污染物排放量总体上呈下降趋势,2020年NOx、SO_(2)、PM_(2.5)和PM_(10)的排放总量分别为3479.81、13418.5、215702.87和235495.21 t.③将2019年和2020年生物质户外燃烧污染物排放数据与空气质量数据进行时间拟合,发现部分城市在两个年份的春季秸秆集中燃烧时段均发生了重污染天气事件,且大气污染物浓度峰值与生物质户外燃烧排放污染物峰值出现的时间一致.研究显示,近年来东北三省生物质户外燃烧管控工作成效明显,大气污染物排放量总体上呈下降趋势,但仍然是东北三省部分城市春季发生重污染天气事件的重要原因之一,对部分生物质户外燃烧污染物排放量较大的城市应进一步严格秸秆禁烧等防控措施.该研究建立的生物质户外燃烧源网格化清单,可以更好地服务于区域空气质量数值模拟研究,应用在大气污染成因分析等多个方面,为制定更为精准的大气污染防治措施提供技术支撑.

The outdoor combustion of biomass is an important pollution source that affects ambient air quality.As important production area in China,the analysis of biomass outdoor combustion of biomass in the three northeastern provinces can provide a basis for the comprehensive utilization of local straw resources and the improvement of environmental quality.Based on the Fire Inventory from NCAR(FINN),the spatiotemporal distribution characteristics of biomass outdoor combustion fire points in three northeastern provinces from 2016 to 2020 was analyzed.Based on air quality monitoring data,the causes of heavy pollution weather were analyzed,and a grid based inventory of biomass outdoor combustion sources for numerical simulation was established.The results show that:(1)The number of fire points in the three northeastern provinces significantly decreased from 2018 to 2019 compared with 2016 to 2017.In 2020,there was an increase in fires,mainly occurring in spring and autumn,with relatively more fires in spring.In spring,there were relatively more fires mainly distributed in the Northeast Plain,namely the eastern and western parts of Heilongjiang Province and the western part of Jilin Province.The number of fire points in other areas were relatively small,showing a scattered distribution characteristic.(2)This study established a grid based inventory of biomass outdoor combustion sources in the three northeastern provinces from 2016 to 2020,with a spatial resolution of 3 km.The types of pollutants monitored include SO_(2),NOx,CO,NMVOC,NH_(3),PM_(10),PM_(2.5),BC and OC.The total pollutant emissions from 2016 to 2020 showed an overall downward trend,and the total emissions of NOx,SO_(2),PM_(2.5) and PM_(10) were 3,479.81,13,418.5,215,702.87 and 235,495.21 tons in 2020,respectively.(3)By time fitting the outdoor biomass combustion pollutant emission data in 2019 and 2020 with air quality data,it was found that some cities experienced heavy pollution weather events during the spring straw concentrated combustion period in those two years,and the peak concentration of atmospheric pollutants was consistent with the peak emission of pollutants from outdoor biomass combustion.The results indicate that in recent years,the outdoor biomass combustion control measures in the three northeastern provinces have achieved significant results,and the overall emission of air pollutants is showing a downward trend.However,it is still one of the important factors for heavy pollution weather events in some cities in spring.For cities with high emissions of pollutants from outdoor biomass combustion,strict measures such as banning straw combustion should be further implemented.The grid based inventory of biomass outdoor combustion established in this study can better serve regional air quality numerical simulation research,apply in various aspects such as air pollution cause analysis,and provide technical support for formulating more accurate air pollution prevention and control measures.