2014—2019年中国秸秆焚烧火点的地理特征分析

客观、精细地刻画秸秆火点的地理空间分布特征,对科学引导作物秸秆焚烧和提高行政监管效率具有重要意义。基于2014—2019年中国区域内Satsee-Fire火点数据集和地形、社会经济数据建立的中国秸秆火点数据库和自然-人口-经济数据库,本研究采用GIS分析工具和数理统计方法,剖析了中国秸秆火点在地形、公共交通和人口-经济三方面7个因子之下的空间格局特征,结果表明：① 秸秆焚烧现象集中发生在高程低于250 m、坡度低于8°的区域,而位于北向坡和南向坡的秸秆火点数分别占总数的42.65%、37.36%。② 秸秆焚烧现象在机场和铁路禁燃区内呈不同的空间格局特征。距机场愈远秸秆焚烧行为愈普遍,机场禁燃区的秸秆焚烧有近六成发生在距机场11~15 km处;而铁路禁燃区内的秸秆火点分布较为均衡,总体呈内部圈层较外部区域略微密集态势,空间上火点密度整体随纬度增加而逐步增加,山西、内蒙古、河北及东三省铁路禁燃区火点数占总数的76.88%。③ 近七成的秸秆火点发生在人口密度低于250人/km2的县域,而58.17%的秸秆火点发生在年GDP低于100亿元的县域;秸秆焚烧现象与县域人口密度、GDP水平存在负相关关系,即县域人口密度愈大、县域经济愈发达,发生秸秆焚烧的现象愈为鲜见。

Analyzing geographical characteristics of straw burning in China during 2014-2019

Objectively and precisely depicting the spatial distribution characteristics of straw burning is of great significance to scientifically guide the prohibition of straw burning and improve the efficiency of administrative supervision. Based on Satsee-Fire point datasets in China during 2014-2019, natural environment and population-economy data, China's straw fire points database and nature-population-economics database established by terrain, social and economic data, this study used GIS analysis tools and mathematical statistics methods to examine the distribution characteristics of straw burning fire points in China during the 6 years under the influences of 7 factors in 3 aspects including terrain, public transport and the population-economy. The results showed that: (1) straw burning phenomenon concentrated in areas whose elevation was less than 250 m and gradient was less than 8°. And the number of fire points which are located on the north slope or the south slope accounted for 42.65% and 37.36% of the total, respectively. (2) Straw burning presented different spatial characteristics in the forbidden area of airports and railways. The farther away from the airport, the more common the straw burning was. Approximately 60% of the straw burning in the forbidden area of the airports took place 11-15 km away from the airport. However, the distribution of straw burning fire points in the forbidden area of railways were more balanced, and the internal circle was slightly more dense than the external region on the whole. In terms of space, the fire point density increased gradually with the increase of latitude. The number of fire points in the forbidden area of railways in Shanxi, Inner Mongolia, Hebei and the three provinces of Northeast China accounts for 76.88% of the total. (3) Nearly 70% of straw burning occurred in countied with a population density of less than 250 people /km2, while 58.17% occurred in counties with annual GDP less than 10 billion yuan. There was a negative correlation between the phenomenon of straw burning and the population density and GDP level of the county, that is, the larger the population density and the more developed the county economy was, the rarer the phenomenon of straw burning was.