摘要
PM_(2.5)是形成雾霾天气的重要污染物,探索PM_(2.5)污染的时空演化规律及空间异质性特征对空气污染的精准治理具有重要意义。基于2000—2018年陕西省县域PM_(2.5)浓度数据,采用重心模型、空间自相关分析等方法,对PM_(2.5)污染的时空演化态势进行了系统研究。结果表明,2000—2018年,陕西省PM_(2.5)浓度年均值经历了前期小幅波动下降、中期急剧上升、后期大幅波动下降的倒“N型”波动变化过程,2011年是PM_(2.5)浓度年均值波动变化的重要“拐点”;PM_(2.5)浓度年均值低于一级浓度限值(15μg/m^(3))的低污染县(区)占比较少且变化不稳定,15~35μg/m^(3)(二级浓度限值)比例有所增加,35~70μg/m^(3)的比例持续减少,反映大多数县(区)未来的PM_(2.5)污染将逐步控制在二级浓度限值以下,空气质量持续好转;在空间分布上,PM_(2.5)浓度年均值具有明显的区域分异;PM_(2.5)浓度年均值在2000—2005年、2005—2010年、2010—2015年、2015—2018年4个阶段有8种“升—降”时序演化类型,以“D-R-D-D”类型的县(区)占绝对比例(59.81%)。重心分析表明陕西省PM_(2.5)污染重心出现西南向东北方向移动轨迹,在空间上大致呈现关中污染突出且西高东低、陕北和陕南污染较轻且相对均衡的空间格局与趋势。PM_(2.5)浓度年平均值在空间上表现出正的空间自相关,空间集聚性总体呈现先降后平再升的时间演化趋势;绝大多数县(区)为“高-高”类型集聚和“低-低”类型集聚,趋同趋势明显,两极分化较严重。
PM_(2.5)is an important pollutant forming haze weather.Exploring the temporal and spatial evolution law and spatial heterogeneity of PM_(2.5)pollution is of great significance to the accurate treatment of air pollution.Based on the county PM_(2.5)concentration data of Shaanxi province from 2000 to 2018,this paper systematically studies the temporal and spatial evolution trend of PM_(2.5)pollution by using the methods of gravity center model and spatial autocorrelation analysis.The results showed that from 2000 to 2018,the annual mean value of PM_(2.5)concentration in Shaanxi province experienced an inverted“N-type”of small fluctuation decline in the early stage,short sharp rised in the middle stage and large fluctuation decline in the later stage.2011 was an important“inflection point”for the fluctuation of the annual mean value of PM_(2.5)concentration.The annual mean value of PM_(2.5)concentration was lower than the primary concentration limit(15μg/m^(3))of low pollution counties(districts)account for relatively small and unstable changes,the proportion of 15~35μg/m^(3)(secondary concentration limit)had increased,and the proportion between 35~70μg/m^(3)continues to decrease,reflecting that the PM_(2.5)pollution in most counties(districts)will be gradually controlled below the secondary concentration limit in the future.In terms of spatial distribution,the average annual value of PM_(2.5)concentration had obvious regional differentiation.The annual mean value of PM_(2.5)concentration had eight“Rise-Decline”time series evolution types in the four stages of 2000—2005,2005—2010,2010—2015 and 2015—2018,and the counties(districts)of“D-R-D-D”type account for the absolute proportion(59.81%).The gravity center analysis showed that the PM_(2.5)pollution gravity center in Shaanxi province moves from southwest to northeast,which roughly presents the spatial pattern and trend of prominent pollution in Guanzhong,high in the west and low in the east,and light pollution in northern and southern Shaanxi.The annual average value of PM_(2.5)concentration showed positive spatial autocorrelation in space,and the spatial agglomeration generally showed the time evolution trend of first falling,then leveling and then rising.Most counties(districts)were“High-High”type agglomeration and“Low-Low”type agglomeration,with obvious convergence trend and serious polarization.
作者
刘宇峰
原志华
杨军军
郭玲霞
许晓婷
安彬
LIU Yu-feng;YUAN Zhi-hua;YANG Jun-jun;GUO Ling-xia;XU Xiao-ting;AN Bing(Xianyang Normal University,School of Resource&Environment and Historical Culture,Xianyang 712000,Shaanxi,China;Xianyang Normal University,School of Economics and Management,Xianyang 712000,Shaanxi,China;School of Tourism&Environment,Ankang University,Ankang 725000,Shaanxi,China)
出处
《湖北农业科学》
2022年第5期127-134,138,共9页
Hubei Agricultural Sciences
基金
国家自然科学基金项目(41901050)
陕西省科技计划项目(2021KRM033)
陕西省社科界重大理论与现实问题研究项目(2021ND0409)
陕西(高校)哲学社会科学重点研究基地项目(20JZ098)
咸阳师范学院教学改革项目(2017Y009,2019Z013)
陕西省大学生创新创业训练项目(S201910722016)
咸阳师范学院青蓝人才项目(XSYQL201805)。
关键词
PM_(2.5)
重心模型
空间自相关
时空演化
陕西省
PM_(2.5)
center of gravity model
spatial autocorrelation
spatiotemporal evolution
Shaanxi province
作者简介
刘宇峰(1981-),男,山西忻州人,副教授,博士,主要从事环境演变与区域发展研究,(电话)13152341611,(电子信箱)yfliu518@163.com。
