基于MODIS火点数据分析南北方省份生物质开放式燃烧与排放特征

Based on MODIS fire pixel location data to characterize the biomass burning and air pollutants emissions in northern and southern China

利用2018年全国范围内的MODIS火点数据,结合土地利用数据信息,运用地理信息系统空间分析方法和统计分析方法,以火点数据、生物量及各污染物排放量为指标,分析了南北方省份生物质开放燃烧的时空特征.计算结果显示,北方省份森林火灾、草原火灾、秸秆露天焚烧生物量分别为107×10^(4)、74×10^(4)、498×10^(4) t,南方省份则分别为344×10^(4)、106×10^(4)、164×10^(4) t.研究结果表明:(1)地域因素及气象因素是影响生物质开放燃烧时空特征的主要因素.(2)北方省份生物质开放式燃烧以秸秆露天焚烧为主,森林火灾主要因气候导致.南方省份生物质开放式燃烧以森林火灾为主,高发于春季,主要因南方存在"炼山"整地的传统营林措施.(3)南方省份虽然整体生物质开放式燃烧活动水平较北方省份低,但污染物排放强度较北方省份要高.

In this study, the open-fire data obtained from MODIS,the type of land-use in China in 2018 were utilized to estimate the quantity of biomass burning and the emissions of the air pollutants. The spatial-temporal features of the biomass burning were characterized and analyzed by using geographic information system(GIS) technology. The results of estimation show that the amount of burned forest, grass, and straw were 1.07,7.74,and 4.98 million tons in northern China, while that were 3.44,1.06,and 1.64 million tons in southern China, respectively. The results show that:(1) the regional factors and meteorological condition are the main driving forces affecting the spatial-temporal feature of biomass burning.(2) the open-fire in northern China is dominated by open burning of straw, and forest fires are mainly caused by the climate, e.g. hot and dry season. The open-fire in southern China is dominated by forest fires, with a high incidence in spring, mainly due to the traditional behavior of "slash burning" in the south.(3) Although the overall biomass burning activity level in southern China is lower than that in northern China, the air pollutant emission intensity is higher than that in northern China.