2015~2022年兰州市中心城区大气环境容量变化特征分析  

Analysis of the changes of atmospheric environmental capacity in the central urban area of Lanzhou from 2015 to 2022

作　　者：杨山泉 瞿德业[1,2] 谌越 杨明月 YANG Shanquan;QU Deye;SHEN Yue;YANG Mingyue(College of Geography and Environmental Science,Northwest Normal University,Lanzhou 730070,Gansu,China;Key Laboratory of Oasis Resources and Sustainable Development in Gansu Province,Lanzhou 730070,Gansu,China)

机构地区：[1]西北师范大学地理与环境科学学院,甘肃兰州730070 [2]甘肃省绿洲资源环境与可持续发展重点实验室,甘肃兰州730070

出　　处：《地球化学》2024年第2期221-233,共13页Geochimica

基　　金：西北师范大学青年教师科研能力提升计划项目(NWNW-LKQN2020-05)资助。

摘　　要：本研究利用2015~2022年气象资料,对大气环境容量计算方法--A值法进行修正,计算出兰州市中心城区不同季节的A值为春季4.14×10^(4)km^(2)、夏季3.51×10^(4)km^(2)、秋季1.28×10^(4)km^(2)、冬季1.12×10^(4)km^(2)。运用修正A值法,考虑污染物的干、湿沉降清除量和化学转化清除量,计算兰州市中心城区6种大气污染物(O3、NO_(2)、CO、SO_(2)、PM2.5和PM10)在8年间四季变化量及大气环境容量,并对修正A值法的主要参数(风速、背景值浓度、干沉降速率和降水量)在±30%范围内进行调整,系统分析污染物的大气环境容量对各参数变化的敏感性。结果表明,8年间兰州市中心城区的空气质量不断改善。除O3外,其他污染物在春、夏季的大气环境容量高于秋、冬季。O3大气环境容量一直在无环境容量上波动;NO_(2)大气环境容量呈“M”型变化,2020年达到最大值(3.59×10^(4) t);PM2.5大气环境容量呈波动增长趋势,2022年达到最大值(2.04×10^(4) t);其他污染物的大气环境容量逐年增加。在进行污染源控制时,首要任务是巩固CO和SO_(2)的防治成果,并以O3、PM10和PM2.5的污染防控为主要目标。参数敏感性分析结果显示,风速和污染物背景值浓度对大气环境容量的影响很大,污染物大气环境容量的变化范围为−40%~70%,CO、SO_(2)背景值浓度在±30%范围内变化,其大气环境容量变化分别为±13.71%和±4.52%。干沉降速率和降水量影响甚微,污染物环境容量变化仅在±4.16%以内。In this study,the A-value method for calculating atmospheric environmental capacity is revised on the basis of meteorological data of the central urban area of Lanzhou from 2015 to 2022.Parameters related to the removal by dry and wet deposition and chemical transformation of pollutants were adjusted in this revised method.The A-values for different seasons in the central urban area of Lanzhou calculated using the revised method are as follows:spring:4.14×10^(4) km^(2),summer:3.51×10^(4) km^(2),autumn:1.28×10^(4) km^(2),and winter:1.12×10^(4) km^(2).Variations in the four seasons and the total atmospheric environmental capacity of six air pollutants in the central urban area of Lanzhou over an eight-year period were also calculated.The sensitivity of the environmental capacity of pollutants to changes in the main parameters(wind speed,background concentration,dry deposition rate,and precipitation)was analyzed by adjusting them within a range of±30%using the revised A-value method.The results indicate that the air quality in the central urban area of Lanzhou has continuously improved over the past eight years.In terms of seasonal variation patterns,except for O3,the environmental capacities of other pollutants are higher in spring and summer than in autumn and winter,while O3 exhibits higher environmental capacity in autumn and winter than in spring and summer.The atmospheric environmental capacity for O3 has been fluctuating around zero environmental capacity.The atmospheric environmental capacity for nitrogen dioxide(NO_(2))exhibited an“M”shaped variation,reaching its maximum value of 3.59×10^(4) tons in 2020.The atmospheric environmental capacity for PM2.5 showed a fluctuating increasing trend,reaching a maximum value of 2.04×10^(4) tons in 2022.The atmospheric environmental capacity for the remaining pollutants showed a year-by-year increase.Regarding pollution source control,the priority is to consolidate the results of carbon monoxide(CO)and sulfur dioxide(SO_(2))control,with a focus on the preven

关 键 词：大气环境容量 修正A值法 干湿沉降 化学转化 敏感性分析 

分 类 号：X51[环境科学与工程—环境工程]