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381.
ABSTRACTInteraction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas in the current literature. This paper sets out a simultaneous equation model to investigate the spillover effect of environmental pollution between China’s peripheral areas utilizing the panel data of 218 cities in China. Making use of indicators for measuring the impact on environmental pollution, it identifies that environmental pollution between cities of China has a significant two-way spillover effect. After standardization of variables, it is found that the spillover effect of peripheral areas on urban environmental pollution cannot be neglected. Nearly, a third of the environmental pollution level in a city is induced by the environmental pollution in peripheral areas. If the indicator of environmental pollution in peripheral areas is missing, wrong conclusions will be drawn. Therefore, government should shift the emphasis of environmental regulation from local to global, and improve the overall environmental quality through coordinated management of regional environment. 相似文献
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383.
乌鲁木齐市环境应急监测体系存在的问题及对策 总被引:1,自引:0,他引:1
乌鲁木齐市已发生多起突发性环境污染事故,虽然环境监测部门在为政府和上级主管部门提供公正、科学和规范的技术支持方面发挥了不可替代的作用,但受经验、资金和技术等方面的制约,当前应急监测体系还存在着监测预案不完善、设备配置偏低、信息化程度和技术含量不高等突出问题。为着力解决这些问题,应完善具体的环境风险源污染事故应急监测预案,建立基于GIS平台的环境应急信息系统,增加现场及实验室仪器配置,并通过完善培训考核程序和系统化演练程序来加强应急监测队伍建设。 相似文献
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385.
目的分析北京地区大气温湿廓线对气溶胶垂直分布的影响。方法利用北京地区2017年9月至2018年8月每日两次(08时和20时)的气象探空、地面PM_(2.5)浓度和气溶胶激光雷达消光系数资料,分析不同污染条件下大气温湿廓线与气溶胶消光系数廓线的关系。结果地面PM_(2.5)浓度和210m气溶胶消光系数的相关系数达到0.77。春季、秋季和冬季污染条件下的近地面消光系数约是清洁条件下的5倍,夏季污染条件下的近地面消光系数约是清洁条件下的3倍。相比清洁条件下,污染条件下各季节的大气温度垂直递减率偏小,并且低层大气相对湿度偏大。结论大气温度廓线代表大气层结稳定性,影响气溶胶的扩散高度,而相对湿度廓线与气溶胶吸湿增长密切相关,两者对气溶胶消光系数的垂直分布都有重要影响。 相似文献
386.
土壤重金属污染问题已经成为环境污染的热点问题。以FeS、Na2S、黄铁矿、CaO、黄铁矿+CaO作为稳定剂,应用化学稳定化修复技术对贵州万山地区的2种汞污染程度不同的农田土壤(1号土、2号土)进行修复,并研究稳定剂用量、稳定时间等因素对稳定效率的影响,确定最佳稳定条件。结果显示:在FeS、Na2S、黄铁矿、CaO、黄铁矿+CaO这5种稳定剂中,Na2S的稳定效果最好,对2种土的稳定效率均高达90%左右;对于1号土,最佳稳定条件为:稳定剂Na2S,稳定时间7 d,稳定剂用量S:Hg=1。对于2号土,最佳稳定条件为:稳定剂Na2S,稳定时间7 d,稳定剂用量S:Hg=5。Na2S作为稳定剂通过改变汞在土壤中的形态分布降低污染土壤中汞的浸出毒性。 相似文献
387.
研究了不同水力停留时间(HRT)和农药污染负荷(PPL)下,\"生态沟渠+水平流人工湿地\"和\"生态沟渠+垂直流人工湿地\"系统对农田退水中常规污染物和噻虫嗪的去除效果。结果表明,\"生态沟渠+垂直流人工湿地\"系统对COD、NH4+-N、NO3--N、TN、TP及噻虫嗪的去除率均优于\"生态沟渠+水平流人工湿地\"系统,分别为76%、97%、92%、95%、88%和40%(HRT=2 d),其中噻虫嗪在沟渠段的去除率为17%,在垂直流人工湿地段的去除率为23%。延长HRT、降低PPL均有利于噻虫嗪在组合系统中的去除。对垂直流人工湿地各基质层出水噻虫嗪浓度检测结果表明,运行前期,噻虫嗪在空心砖层去除率最高(8%),主要是由于空心砖对于噻虫嗪的吸附优于沸石和钢渣,随着系统运行,土壤+细沸石层和粗沸石层的去除效率增加,植物吸收与微生物降解作用逐渐占据主导地位。微生物群落结构分析结果显示,生态沟渠段β-变形菌纲和厌氧绳菌纲丰度分别为11%和10%。垂直流人工湿地自上而下芽孢杆菌逐渐增多成为优势菌,β-变形菌和厌氧绳菌逐渐减少。厌氧、好氧交替环境有利于常规污染物和噻虫嗪的去除。 相似文献
388.
To investigate the influence of haze on the chemical composition and formation processes of ambient aerosol particles,PM_(2.5) and size-segregated aerosol particles were collected daily during fall at an urban site of Gwangju,Korea.During the study period,the total concentration of secondary ionic species(SIS) contributed an average of 43.9% to the PM_(2.5) ,whereas the contribution of SIS to the PM_(2.5) during the haze period was 62.3%.The NO_3 and SO~(2-)_4 concentrations in PM_(2.5) during the haze period were highly elevated,being 13.4 and 5.0 times higher than those during non-haze period,respectively.The PM,NO~-_3,SO~(2-)_4,oxalate,water-soluble organic carbon(WSOC),and humic-like substances(HULIS) had tri-modal size distributions peaks at 0.32,1.0,and 5.2 μm during the non-haze and haze periods.However,during the non-haze period they exhibited dominant size distributions at the condensation mode peaking at 0.32 μm,while on October 21 when the heaviest haze event occurred,they had predominant droplet mode size distributions peaking at 1.00 μm.Moreover,strong correlations of WSOC and HULIS with SO~(2-)_4,oxalate,and K+at particle sizes of 1.8 μm indicate that secondary processes and emissions from biomass burning could be responsible for WSOC and HULIS formations.It was found that the factors affecting haze formation could be the local stable synoptic conditions,including the weak surface winds and high surface pressures,the long-range transportation of haze from eastern China and upwind regions of the Korean peninsula,as well as the locally emitted and produced aerosol particles. 相似文献
389.
Li Chen Mengshuang Shi Suhuan Li Shuang Gao Hui Zhang Yanling Sun Jian Mao Zhipeng Bai Zhongliang Wang Jiang Zhou 《环境科学学报(英文版)》2017,29(7):33-40
In 2013,China issued \"Air Pollution Prevention and Control Action Plan(Action Plan)\" to improve air quality.To assess the benefits of this program in Beijing-Tianjin-Hebei(BTH)region,where the density of population and emissions vary greatly,we simulated the air quality benefit based on Ben MAP to satisfy the Action Plan.In this study,we estimate PM_(2.5) concentration using Voronoi spatial interpolation method on a grid with a spatial resolution of 1 × 1 km~2.Combined with the exposure-response function between PM_(2.5) concentration and health endpoints,health effects of PM_(2.5) exposure are analyzed.The economic loss is assessed by using the willingness to pay(WTP) method and human capital(HC) method.When the PM_(2.5) concentration falls by 25% in BTH and reached 60 μg/m~3 in Beijing,the avoiding deaths will be in the range of 3175 to 14051 based on different functions each year.Of the estimated mortality attributable to all causes,3117 annual deaths were due to lung cancer,1924 – 6318 annual deaths were due to cardiovascular,and343 – 1697 annual deaths were due to respiratory.Based on WTP,the estimated monetary values for the avoided cases of all cause mortality,cardiovascular mortality,respiratory mortality and lung cancer ranged from 1110 to 29632,673 to 13325,120 to 3579,1091 to 6574 million yuan,respectively.Based on HC,the corresponding values for the avoided cases of these four mortalities were 267 to 1178,161 to 529,29 to 143 and 261 million yuan,respectively. 相似文献
390.