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41.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) in street soil dust from streets in Kumasi Metropolis in the Ashanti Region of the Republic of Ghana have been measured in this study. The concentrations of the various types of PAHs identified in this study are as follows: Naphthalene (m/e 128) – 41,700 μg/kg, Acenaphthylene (m/e 152) – 99,300 μg/kg, Acenaphthene (m/e 154) – 111,200 μg/kg, Fluorene (m/e 166) – 8,900 μg/kg, Carbazole (m/e 167) – 3,500 μg/kg, phenathrene (m/e 178) – 12,900 μg/kg, Anthracene (m/e 178) – 5,400 μg/kg, Fluoranthene (m/e 202) – 16,200 μg/kg, Pyrene (m/e 202) – 15,000 μg/kg, Benzo[a]anthracene (m/e 228) – 13,800 μg/kg, Chrysene (m/e 228) – 33,600 μg/kg, Benzo[k]fluoranthene (m/e 252) – 45,700 μg/kg, Benzo[a]pyrene (m/e 252) – 27,900 μg/kg, Perylene (m/e 252) – 57,200 μg/kg and Benzo[g, h, i]perylene (m/e 276) – 47,000 μg/kg. The results of the study shows that road users, like resident living in buildings within these areas, those engaged in commercial activities like hawking, and the general public are at risk of exposure to the toxic effects of the various types of PAHs from the exhaust of vehicles into the environment. According to these results, there is the potential for exposure to high levels of PAHs for road users and those living in urban environments or along highways.  相似文献   
42.
根据煤矿区规划环评的现状,提出了几种煤矿区规划环评中的大气环境影响预测方法,并将多源叠加的高斯模型法和箱模式法分别应用于榆神矿区和神东矿区的大气环境影响预测中.结果表明,多源叠加的高斯模型法灵活多变,而箱模式简单易行.  相似文献   
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44.
首先给出了以活性污泥反应器为载体,基于呼吸速率的BOD在线测量的原理,然后通过呼吸速率方法确定了在线测量过程需要确定的产率系数,给出了饱和常数在线校正的方法,最终通过对葡萄糖人工配水BOD进行了测量.测量结果与理论分析进行了比较,最终证明基于呼吸速率在线测量BOD是基本可行的.  相似文献   
45.
基于255 m气象塔天津地区污染天气高空风特征研究   总被引:3,自引:1,他引:3  
基于2016年4月—2017年3月天津地区地面、255 m气象塔和风廓线监测数据,结合数值模拟,研究天津污染天气分析中高空风特征,以期进一步提高污染天气预报准确率.结果表明:高空风速和风向分析对污染天气趋势判断有重要作用,如冠层以上高度风速、300~1500 m风向对PM2.5污染程度的指示效果好于近地面同类数据;在选取高空风速指标时,应尽量避免边界层顶附近高度风速数据选取,如使用300 m和600 m风速和作为指标要好于300、600和900 m风速和作为指标.而其是否有利于污染扩散判断的临界阈值为10~15 m·s-1,小于10 m·s-1时水平扩散条件不利于污染物扩散,大于15 m·s-1时有利于污染物扩散.分析高空风向时,需要考虑输送高度和Ekman螺线的影响,与地面不同,300~1500 m高空风分析时,有利于出现污染天气的风向为西风、西南风和南风,而地面仅为南风和西南风;当1500 m高度呈现东风、偏东风和东南风时,天津地区受来自渤海的气流影响明显,污染气象条件有利于污染物扩散,空气质量以良好为主.  相似文献   
46.
本研究运用最小相关系数法(MRS),使用元素碳(EC)作为示踪物,得到一次排放的质量吸光效率(MAEp),结合黑碳仪(AE33)和有机碳/元素碳分析仪获得实测的质量吸光效率MAEt,进而通过MAEt/MAEp的比值得出吸光增强系数(Eabs).采样站点位于广州市城区暨南大学大气超级监测站,采样时间涵盖了干季(2019年1月26日~3月31日)和湿季(2018年5月1日~7月31日).对广州市城区的黑碳气溶胶及其光学特征进行分析,EC在干季的平均浓度(1.93±1.38)μgC/m3高于湿季(1.46±0.75)μgC/m3,而Eabs520在干季的均值(1.26±0.34)低于湿季(1.63±0.55).Eabs520在干湿季的日变化差异明显,但有机碳(OC)、EC、OC/EC、波长指数(AAE470-660)均为干季高于湿季.分析发现气溶胶负载补偿参数k值与Eabs520在湿季呈现出较好的相关性,而在干季相关性较差,可能与生物质燃烧的影响有关;探讨了O3、NO2和SOC/OC对Eabs520的影响,在干季O3Eabs520的相关性较差(R2=0.21),在湿季较好(R2=0.46),SOC/OC却展现出了相反的关系,而NO2在干季和湿季与Eabs520的相关性都较差(R2=0.01),并发现温度对Eabs520存在一定的影响.通过后向轨迹聚类分析发现,长距离传输气团的的黑碳Eabs520值较高.  相似文献   
47.
城市环境污染的植物监测   总被引:12,自引:0,他引:12  
依据国内外已有的资料,探讨了利用指示植物器官、或个体的形态变化,生态适应特征,组织化学成分与生理生化过程改变,以及种群与群落学特征等对城市大气、水体、土壤污染物的反应来监测环境污染的方法和实施途径,并对使用指示植物监测环境污染的优点和存在的问题进行了分析。  相似文献   
48.
Studies evaluating human–wildlife interactions (HWIs) in a conservation context often include psychometric scales to measure attitudes and tolerance toward wildlife. However, data quality is at risk when such scales are used without appropriate validation or reliability testing, potentially leading to erroneous interpretation or application of findings. We used 2 online databases (ProQuest Psych Info and Web of Science) to identify published HWI studies that included attitude and tolerance. We analyzed these studies to determine the methods used to measure attitudes or tolerance toward predators and other wildlife; determine the proportion of these methods applying psychometric scales; and evaluate the rigor with which the scales were used by examining whether the psychometric properties of validity and reliability were reported. From 2007 to 2017, 114 published studies were identified. Ninety-four (82%) used questionnaires and many of these (53 [56%]) utilized a psychometric scale. Most scales (39 [74%]) had at least 1 test of reliability reported, but reliance on a single test was notable, contrary to recommended practice. Fewer studies (35 [66%]) reported a test of validity, but this was primarily restricted to structural validity rather than more comprehensive testing. Encouragingly, HWI investigators increasingly utilized the necessary psychometric tools for designing and analyzing questionnaire data, but failure to assess the validity or reliability of psychometric scales used in over one-third of published HWI attitude research warrants attention. We advocate incorporation of more robust application of psychometric scales to advance understanding of stakeholder attitudes as they relate to HWI.  相似文献   
49.
Despite widespread recognition of the major threat to tropical forest biological diversity and local food security posed by unsustainable bushmeat hunting, virtually no long‐term studies tracking the socioecological dynamics of hunting systems have been conducted. We interviewed local hunters and collected detailed hunting data to investigate changes in offtake and hunter characteristics over 10 years (2001–2010) in Dibouka and Kouagna villages, central Gabon, in the context of hunter recollections of longer term trends since the 1950s. To control for changes in hunter behavior, such as trap location and characteristics, we report hunting offtake data per trap. Our results suggest the hunting area was already highly depleted by 2001; local hunters reported that 16 large‐bodied prey species had become rare or locally extirpated over the last 60 years. Overall, we observed no significant declines in hunting offtake or changes in species composition from 2001 to 2010, and offtakes per trap increased slightly between 2004 and 2010. However, trapping distance from the villages increased, and there was a switch in hunting techniques; a larger proportion of the catch was hunted with guns in 2010. The number of hunters declined by 20% from 2004 to 2010, and male livelihood activities shifted away from hunting. Hunters with the lowest hunting incomes in 2004 were more likely than successful hunters to have moved away from the village by 2010 (often in response to alternative employment opportunities). Therefore, changes in trap success (potentially related to biological factors) were interacting with system‐level changes in hunter number and composition (related to external socioeconomic factors) to produce a relatively static overall offtake. Our results highlight the importance of understanding the small‐scale context of hunting to correctly interpret changes or apparent stasis in hunting effort and offtake over time. Cambio Social y Ecológico a lo Largo de Una Década en un Sistema de Cacería Aldeana, Gabón Central  相似文献   
50.
The biodegradability of poly--hydroxybutyrate and poly--caprolactone in soil compostage before and after irradiation of the polymers for 192, 425, and 600 h in a Weather-Ometer was examined. The biodegradability tests were done in soil compostage at pH 7.0, 9.0, and 11.0 to assess the influence of this parameter on degradation. The rate of degradation was directly proportional to the soil alkalinity. Poly--hydroxybutyrate showed the greatest weight loss and aging in a Weather-Ometer did not significantly increase the biodegradation, except when the polymer was aged for 425 h and buried in soil compostage of pH 11.0.  相似文献   
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