摘要
习近平总书记在全国生态环境保护大会明确指出“要以空气质量明显改善为刚性要求,强化联防联控,基本消除重污染天气,还老百姓蓝天白云、繁星闪烁”,不断提升“蓝天幸福感”关乎我国生态文明建设,为大气污染防治指明了方向.PM_(2.5)是空气污染程度衡量的主要指标之一,准确认知PM_(2.5)时空分布特征及成因是大气污染治理的基础.本文首先利用陕西省2015—2021年PM_(2.5)浓度的地面站点监测数据与遥感产品数据,分析了PM_(2.5)浓度时空分布特征.然后,利用Mann-Kendall趋势检验方法分析了陕西省PM_(2.5)浓度的年变化趋势和月变化趋势.最后,以污染较为严重的关中平原3个地级市为例,利用拉格朗日混合单粒子轨道模型(HYAPLIT)后向轨迹模型和聚类分析等方法,模拟了PM_(2.5)污染物气团轨迹,并选取西安为典型地区分析了新冠肺炎疫情(COVID-19)期间在人为活动管控对PM_(2.5)浓度的变化影响.结果表明:(1)从空间分布来看,关中平原PM_(2.5)浓度较高,陕南(安康、汉中、商洛)和陕北(榆林、延安)地区PM_(2.5)浓度较低,月平均浓度呈现U型变化规律.(2)通过MannKendall趋势检验分析可知,2015—2021年陕西省PM_(2.5)浓度整体呈下降趋势,按不同月份分析下降趋势发现秋、冬季呈显著降低趋势.(3)由后向轨迹分析可知,西安、咸阳、渭南的春冬季主要受长距离气团影响,夏秋季主要受短距离气团影响.(4)在西安市人口出行强度减少的条件下,与2015—2019年PM_(2.5)浓度月均值相比,2020年COVID-19期间西安2月—4月PM_(2.5)浓度呈降低趋势,2月空气质量明显有好转,PM_(2.5)浓度与2019年同期相比降低17%.
In the last few decades,due to high energy consumption and rapid urbanization,China is facing severe air pollution problem.The government has attached great attention to this problem.The national and local governments have carried out a series of measures to prevent and control pollution.As one of the main air pollutants,PM_(2.5) can cause various respiratory diseases then increase resident mortality rates.Accurate recognition of the spatial and temporal variations of PM_(2.5) is the basis to make scientific,reasonable and valid measures to prevent and control PM_(2.5) pollution.In this work,based on the in-situ monitoring data and remote sensing PM_(2.5) concentration product in Shaanxi Province from 2015 to 2021,the spatial and temporal distribution characteristics of PM_(2.5) concentration was analyzed,the annual and monthly changing trend of PM_(2.5) concentration in Shaanxi Province was estimated using Mann-Kendall trend test method.Taking three prefecture-level cities with serious PM_(2.5) pollution as examples,we analyzed the trajectory of PM_(2.5) pollutant air mass by using the backward trajectory model of hybrid single particle lagrangian trajectory intergrsted trajectory(HYAPLIT)and cluster analysis.The strictly restricted human activities in Xi'an city during the COVID-19 occurred in February,March and April in 2020 provided a unique opportunity to explore the human activity effect on PM_(2.5) pollution.The results show that:①from the spatial distribution of PM_(2.5) concentration in Shaanxi Province,it is indicated that Guanzhong Plain is the highest,the southern and northern region of Shaanxi is the lowest.The monthly concentration variation is a U-shape curve;②according to the Mann-Kendall trend test,generally the PM_(2.5) concentration in Shaanxi Province is decreasing from 2015 to 2021.From the specific month,months in autumn and winter showed more significant decrease trend than other seasons;③the backward trajectory indicated that Xi'an,Xianyang and Weinan are mainly affected by long-rang
作者
张丽萍
王旭峰
何映月
张利瑞
罗亚刚
朱培世
潘瑞昇
田丰
王波
张松林
ZHANG Liping;WANG Xufeng;HE Yingyue;ZHANG Lirui;LUO Yagang;ZHU Peishi;PAN Ruisheng;TIAN Feng;WANG Bo;ZHANG Songlin(College of Geography of Environment Science,Northwest Normal University,Lanzhou 730070;Northwest Institute of Eco-environment and Resources,Chinese Academy of Sciences,Lanzhou 730000;Bureau of Water Resources in Tanchang,Tanchang 748500;The Third Institute of Geology and Mineral Exploration,Gansu Provincial Bureau of Geology and Minerals Exploration and Development,Lanzhou 730050)
出处
《环境科学学报》
CAS
CSCD
北大核心
2023年第6期94-109,共16页
Acta Scientiae Circumstantiae
基金
国家自然科学基金项目(No.51068025)。
