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71.
A biennial integrated survey, based on the use of vascular plants for the bioindication of the effects of tropospheric ozone together with the use of automatic analysers of ozone, as well as the mapping of lichen biodiversity was performed in the area of Castelfiorentino (Tuscany, central Italy). Photochemically produced ozone proved to be a fundamental presence during the warm season, with maximum hourly means reaching 114 ppb, exceeding the information threshold as fixed by EU: the use of supersensitive tobacco Bel-W3 confirmed the opportunity of carrying out detailed cost-effective monitoring surveys. The potential for didactical and educational implications of this methodology are appealing. Critical levels set up for the protection of vegetation have exceeded considerably. The comparison of biomass productivity in sensitive and resistant individuals (NC-S and NC-R white clover clones, in the framework of an European network) provided evidence that ambient ozone levels are associated with relevant reduction (up to 30%) in the performance of sensitive material; effects on flowering were also pronounced. The economic assessment of such an impact deserves attention. Mapping of epiphytic lichen biodiversity – which has been used to monitor air quality worldwide – was not related to ozone geographical distribution as depicted by tobacco response. 相似文献
72.
It is well established that trees help to reduce air pollution, and there is a growing impetus for green belt expansion in urban areas. Identification of suitable plant species for green belts is very important. In the present study, the Air Pollution Tolerance Index (APTI) of many plant species has been evaluated by analyzing important biochemical parameters. The Anticipated Performance Index (API) of these plant species was also calculated by considering their APTI values together with other socio-economic and biological parameters. Based on these two indices, the most suitable plant species for green belt development in urban areas were identified and recommended for long-term air pollution management. 相似文献
73.
杉木地理种源遗传变异的RAPD分析 总被引:11,自引:0,他引:11
应用随机扩增多态性DNA技术对我国12个有代表性的杉木地理种源遗传多样性进行分析,从80个随要引物中筛选出20个进行扩增,共扩增出149个DNA片段,其中具多态性的片段有115个,占77.18%%,表明极木地理种源间具有丰富的DNA序列多态性、平均每个引物提供7.45个RAPD标记的信息量,扩增出的DNA片段大小一般为150到2000bp范围之间,12个杉木地理种源间遗传距离变幅为0.193-0.4467,聚类结果表明,在0.2664处,广东信宜,广西梧州,湖南会同,湖南江华,贵州锦屏,江西全南聚为一类,福建沙县,浙江开化,湖北咸宁,安徽休宁聚为一类,四川雅安,陕西南郑各为一类,图2表2参15 相似文献
74.
Diversity of antibiotic resistance genes and encoding ribosomal protection proteins gene in livestock waste polluted environment 总被引:1,自引:0,他引:1
Chunyan Li Cheng Jiang Zhiyang Wu Xuejiao An Hailan Wang 《Journal of environmental science and health. Part. B》2018,53(7):423-433
The rapid development and increase of antibiotic resistance are global phenomena resulting from the extensive use of antibiotics in human clinics and animal feeding operations. Antibiotics can promote the occurrence of antibiotic resistance genes (ARGs), which can be transferred horizontally to humans and animals through water and the food chain. In this study, the presence and abundance of ARGs in livestock waste was monitored by quantitative PCR. A diverse set of bacteria and tetracycline resistance genes encoding ribosomal protection proteins (RPPs) from three livestock farms and a river were analyzed through denaturing gradient gel electrophoresis (DGGE). The abundance of sul(I) was 103 to 105 orders of magnitude higher than that of sul(II). Among 11 tet-ARGs, the most abundant was tet(O). The results regarding bacterial diversity indicated that the presence of antibiotics might have an evident impact on bacterial diversity at every site, particularly at the investigated swine producer. The effect of livestock waste on the bacterial diversity of soil was stronger than that of water. Furthermore, a sequencing analysis showed that tet(M) exhibited two genotypes, while the other RPPs-encoding genes exhibited at least three genotypes. This study showed that various ARGs and RPPs-encoding genes are particularly widespread among livestock. 相似文献
75.
改革开放以来,外商直接投资(FDI)的涌入为中国经济发展注入了新活力,并成为中国经济高速增长的重要引擎之一。然而,随着康菲石油渤海漏油事故、江苏启东王子造纸排污和阿玛尼污染投诉等涉外污染事件报道频出,学术界对于FDI涌入可能带来的负面环境效应表现出一定担忧。现有文献多聚焦于整体层面的FDI环境效应检验,而对其区域差异及原因产生机制的系统探究并不多见。为此,本文从理论判断和命题推演出发,利用2003—2014年中国省际面板数据,以改进熵值法拟合环境污染综合指数,并构建普通面板模型,实证检验了FDI流入对中国环境污染的影响及其区域差异。结果表明,总体而言,"污染光环"假说在中国基本成立,即FDI流入在一定程度上改善了中国环境质量,但不同地区FDI的环境效应有所不同,其主要表现为沿海和内陆地区FDI具有显著的"污染光环"效应,且前者强于后者,而沿边地区FDI具有不明显的"污染天堂"效应。在此基础上,构造面板门槛模型,进一步系统考察了FDI对中国环境污染影响的4种主要吸收能力因素的门槛效应。门槛回归结果表明,FDI对中国环境污染的影响显著存在基于经济发展、环境规制、人力资本和金融发展水平的双门槛效应。经济发展、人力资本和金融发展水平越高,FDI的"污染光环"效应越明显,而适度的环境规制才更有利于FDI环境技术溢出的发挥。基于此,本文建议应进一步全方位地提高对外开放水平,一如既往地积极引进并监督FDI;同时地方政府也需认清地区发展的不平衡性,进而采取差异化的引资政策。 相似文献
76.
Arrebola JP Mutch E Rivero M Choque A Silvestre S Olea N Ocaña-Riola R Mercado LA 《Environment international》2012,38(1):54-61
The organochlorine pesticide p,p′-Dichlorodiphenyltrichloroethane (DDT) was widely used in the early 1960s-70s for vector control in tropical and subtropical areas of South America. Due to its persistence, DDT has a high potential to bioaccumulate in the food chain and living organisms and is a major public health concern, especially in South America.The main purpose of the present study was to investigate predictors of serum and adipose tissue concentrations of p,p′-DDT and its main metabolite, p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE), in an adult cohort (n = 112) from Santa Cruz de la Sierra, Bolivia, using multiple linear regression models. These models explained 29.3-47.8% of the variability in adipose tissue concentrations of p,p′-DDT and p,p′-DDE, respectively, and 32.9-47.0% of that in serum. Main exposure predictors included age, occupational class, residence, diet, smoking habit, and accumulated breastfeeding time.This is one of the few studies to explore predictors of human exposure to these chemicals using a multivariate approach in a South American population. Results show that predictors of human exposure to p,p′-DDT and p,p′-DDE in Santa Cruz de la Sierra may diverge from those found in other populations of the world, due to particular sociodemographic and lifestyle characteristics of this region. 相似文献
77.
Metabolic diversity of the heterotrophic microorganisms and potential link to pollution of the Rouge River 总被引:2,自引:0,他引:2
S.M. Tiquia 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1435-1443
The heterotrophic microbial communities of the Rouge River were tracked using Biolog Ecoplates to understand the metabolic diversity at different temporal and spatial scales, and potential link to river pollution. Site less impacted by anthrophogenic sources (site 1), showed markedly lower metabolic diversity. The only substrates that were utilized in the water samples were carbohydrates. Sites more impacted by anthrophogenic sources (sites 8 and 9) showed higher metabolic diversity. Higher functional diversity was linked to the physico-chemical and biological properties of the water samples (i.e. higher concentrations of DO, DOC, chlorophyll, and bacterial density). Biolog analysis was found to be useful in differentiating metabolic diversity between microbial communities; in determining factors that most influence the separation of communities; and in identifying which substrates were most utilized by the communities. It can also be used as an effective ecological indicator of changes in river function attributable to urbanization and pollution. 相似文献
78.
采用分子生物学手段16S rDNA克隆文库方法对缺氧/好氧膜生物反应器(AO-MBR)的好氧池与缺氧池中细菌进行了多样性研究.实验结果表明,好氧池污泥样品的克隆文库包括9个类群,其中变形菌(Proteobacteria)和拟杆菌(Bacteroidetes)在文库中所占比例最大,分别为37.04%和14.81%;其次是酸杆菌(Acidobacteria)、未培养菌(uncultured bacterium)、绿菌(Chlorobi)和未培养的绿弯菌(uncultured Chloroflexi bacterium)、浮霉状菌(Planctomycetes),分别为11.11%、11.11%、7.41%、7.41%和5.56%;硝化螺旋菌(Nitrospirae)和裸藻门(Euglenozoa)所占比例相对较小,均为1.85%.缺氧池样品克隆文库包括10个类群,其中变形菌(Proteobacteria)、拟杆菌(Bacteroidetes)和未培养菌(uncultured bacterium)在文库中所占比例最大,分别为27.91%、13.95%和12.79%;其次是浮霉状菌(Planctomycetes)、酸杆菌(Acidobacteria)和绿弯菌(Chloroflexi),在文库中所占比例分别为9.3%、9.3%和9.3%;硝化螺旋菌(Nitrospirae)、裸藻门(Euglenozoa)、芽单胞菌(Gemmatimonadetes)和放线菌(Actinobacteria)所占比例相对较少,分别为6.98%、8.14%、1.16%和1.16%.两池细菌的主要类群相似,但菌属及比例有所差异,变形菌是系统中的主要脱氮菌属. 相似文献
79.
现行的泥石流总量计算方法普遍存在计算参数较难获取或难以精确获取的问题,加上汶川地震灾区沟谷内分布大量的由崩塌、滑坡体等形成的固体松散物质;所以多数泥石流总量计算公式在汶川震区存在局限性.参考适用于以崩塌、滑坡体为主要物源的泥石流总量计算公式;分析研究区范围内地形地貌发育状态与降雨因素及其地质条件之间的影响关系;将地貌指数(Strahler积分)应用于泥石流总量计算,尝试解决缺乏降雨数据情况下泥石流总量计算问题.根据“8.13”四川清平群发性泥石流数据初步回归分析得到适合于汶川震区的泥石流总量计算模型. 相似文献
80.
To restore food security to a traditional African cropping system following a sudden loss of seed, genetic diversity must be re-established. This study examines the extent to which Cowpea diversity was reinstated two years after a flood disaster in Gaza Province, Mozambique. The contribution that seed from various sources made to the recovery was assessed using semi-structured interviews and morphological and molecular data. Data suggest that diversity had recovered to some extent yet there was evidence of a narrowing of the genetic base, with fewer rare alleles and differences in the distribution of allele frequencies. Although the main channels for accessing seed after the flood were seed relief and markets, these sources contributed to minimal and different diversity. It appears that diversity was regained primarily through social networking in the form of loans or gifts of seed from friends and relatives. The results of the study are discussed in relation to seed relief approaches. 相似文献