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751.
上海大气氮湿沉降的污染特征 总被引:8,自引:1,他引:7
为探讨上海大气氮湿沉降的污染特征,采集了2007年11月至2008年10月上海雨水样品,分析了大气氮湿沉降浓度,探讨了上海大气湿沉降氮通量及上海市区,市郊和远郊大气氮湿沉降的时空污染特征.结果表明:(1)上海市区、市郊和远郊大气氮湿沉降质量浓度平均值分别为2.96、2.31、2.21 mg/L.从上海大气湿沉降总体来看,大气氮湿沉降劣V类、V类的超标率分别达到51.09%和13.87%.推断大气氮湿沉降的主要来源是机动车辆所排放的大量氮氧化物.(2)除冬季外,其余季节上海市区大气氮湿沉降浓度均大于市郊和远郊;市区和远郊大气氮湿沉降浓度均在秋季最大,市郊大气氮湿沉降浓度在春季最大.(3)上海大气年氮湿沉降通量为78.42 kg/hm~2,同其他区域相比较,属于世界上高氮沉降区域.(4)上海大气月氮沉降通量与月平均降雨量呈显著的线性正相关(p<0.05),说明上海大气氮湿沉降通量主要受降雨量的影响. 相似文献
752.
Hongli Wang Qian Wang Jianmin Chen Changhong Chen Cheng Huang Liping Qiao Shengrong Lou Jun Lu 《环境科学学报(英文版)》2015
The characteristic ratios of volatile organic compounds (VOCs) to i-pentane, the indicator of vehicular emissions, were employed to apportion the vehicular and non-vehicular contributions to reactive species in urban Shanghai. Two kinds of tunnel experiments, one tunnelwith more than 90% light duty gasoline vehicles and the otherwithmore than 60% light duty diesel vehicles, were carried out to study the characteristic ratios of vehicle-related emissions from December 2009 to January 2010. Based on the experiments, the characteristic ratios of C6-C8 aromatics to i-pentane of vehicular emissions were 0.53 ± 0.08 (benzene), 0.70 ± 0.12 (toluene), 0.41 ± 0.09 (m,p-xylenes), 0.16 ± 0.04 (o-xylene), 0.023 ± 0.011 (styrene), and 0.15 ± 0.02 (ethylbenzene), respectively. The source apportionment results showed that around 23.3% of C6-C8 aromatics in urban Shanghai were from vehicular emissions, which meant that the non-vehicular emissions had more importance. These findings suggested that emission control of non-vehicular sources, i.e. industrial emissions, should also receive attention in addition to the control of vehicle-related emissions in Shanghai. The chemical removal of VOCs during the transport from emissions to the receptor site had a large impact on the apportionment results. Generally, the overestimation of vehicular contributions would occur when the VOC reaction rate constant with OH radicals (kOH) was larger than that of the vehicular indicator, while for species with smaller kOH than the vehicular indicator, the vehicular contribution would be underestimated by the method of characteristic ratios. 相似文献
753.
The capabilities of third world countries in dealing withenvironmental problems are often limited by available resources and the tremendous costs of environmental monitoring.This paper attempts to introduce a newmethodology that can be used to derive information aboutenvironmental quality in its spatial and temporal dimensions.This methodology, based on an inquiry-feedback network of 8,000families and iteration with controlled-feedback of expertcommunity, has been first tested in Shanghai, China andprocedurally can be divided into two steps: Base-year evaluationand forecasting. Fuzzy pattern recognition is introduced for thesubjective assessment of the citizens' feelings theirperceived environment and a four-round Delphi-Cross Impactanalysis is conducted for forecasting the environmental changesup to 2000. Results show that the base-year environmentalsituations were poor. In the foreseeable future, the conditionsfor housing, social services, public health, greenspace anddrinking water will be substantially improved. Due to the rapidgrowth of manufacturing, the city will continue its deteriorating trend of air and water quality into the next century according to the forecast. 相似文献
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755.
通过对上海市高尔夫球场农药使用情况的详细调查,结果显示:当前高尔夫球场使用的农药主要包括3大类43种,包含杀菌剂20种、杀虫剂14种和除草剂9种,种类组成及施用量均以杀菌剂为主;施用农药以微毒、低毒农药为主(占69.8%),高毒农药主要为杀虫剂;不同球场农药使用种类、强度和频次等存在较大差异,主要与球场规模、草坪种类及管理水平等有关;当前高尔夫球场农药使用中仍存在农药施用强度较高,农药施用种类较多,品种结构仍有待优化等问题。 相似文献
756.
上海城市绿地系统建设与规划的原则和对策 总被引:8,自引:0,他引:8
针对上海城市绿化现状,强调生态位、生态效益、生物多样性、空间布局和景观割裂等原理在绿地中的重要性,并在此基础上分析探讨了21世纪的上海在绿地系统建设中应如何提高绿化数量、改善绿地质量、提高生物的多样性和空间异质性、发挥生态效益、丰富绿化形式等诸多问题,尝试为今后的规划提供一些对策。 相似文献
757.
以上海市污水治理二期工程物理模型试验数据为基础,通过量纲分析的方法得出了污水排放口上升布置多个喷口时污水场宽度与各影响因素之间的关系式,根据污水场宽度可以确定出上升管理论间距,为实际工程中扩散器长度的确定提供理论依据。 相似文献
758.
759.
Schifter I González-Macías C Miranda A López-Salinas E 《Environmental monitoring and assessment》2005,109(1-3):135-145
Air emission data from offshore oil platforms, gas and oil processing installations and contribution of marine activities
at the Sonda de Campeche, located at the Gulf of Mexico, were compiled and integrated to facilitate the study of long range
transport of pollutants into the region. From this important region, roughly 76% of the total Mexican oil and gas production
is obtained. It was estimated that the total air emissions of all contaminants are approximately 821,000 tons per year. Hydrocarbons
are the largest pollutant emissions with 277,590 tons per year, generated during flaring activities, and SOx in second place
with 185,907 tons per year. Marine and aviation activities contribute with less than 2% of total emissions. Mass of pollutants
emitted per barrel of petroleum produced calculated in this work, are in the range reported by similar oil companies. 相似文献
760.