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981.
淮河流域河南段水生植物多样性评价及其影响因素分析   总被引:3,自引:0,他引:3  
通过对淮河流域河南段开展野外调查及室内监测,分析河流水生植物类群组成及优势物种,从多样性、丰富度、优势度、均匀度4个方面对水生植物进行健康评价,采用CCA分析法探讨影响水生植物的关键环境因素。结果表明,淮河流域河南段共有水生植物38种,隶属于25科33属,分布广泛的优势种为芦苇、水花生、金鱼藻、轮叶黑藻、水蓼、水鳖、篦齿眼子菜。针对健康评价结果,淮河流域河南段水生植物呈现病态到健康状态。分析表明河流生态系统遭受破坏,生态系统呈现不稳定状况,主要原因为水质污染及人为活动干扰强烈。根据水生植物分布与水环境因子CCA响应关系研究,影响水生植物的主要因子为TP、COD、p H、电导率、氨氮。  相似文献   
982.
With intensified contradiction between the rapid development of modern industry and the carrying capacity of natural environment,coordinating the relationship between economic benefits and ecological benefits is a significant issue to be solved for modern industrial engineering.This paper firstly conducts the comparative analysis between traditional and ecological industry as well as traditional and modern industrial engineering,and indicates that eco-industrial engineering is an inevitable choice for sustainable development of modern industrial engineering;Then,based on industrial ecology,environmental economics and sustainable development theory,the connotation and definition of ecoindustrial engineering are proposed,and the theoretical and practical development of the concepts of eco-industrial engineering are further investigated.Furthermore,the research subject,research content,academic system architecture and evaluation methods of eco-industrial engineering are discussed.Finally,combining the current scientific and technological development,we put forward the important scientific value and practical significance of constructing eco-industrial engineering for the utilization of these concepts.  相似文献   
983.
In Colombia, national policies and laws on the protection of vulnerable populations pay specific attention to the sexual and reproductive health needs and rights of internally displaced adolescents. This paper describes how a United Nations Population Fund (UNFPA)-supported programme (September 2000-August 2004) on the sexual and reproductive health of internally displaced adolescents contributed to restoring their dignity as a precursor to promoting their sexual and reproductive health rights. Different forms of the arts were used as basic techniques to discover their body and to provide sexual and reproductive health information and education. The arts were found to play a key role in restoring their dignity. Although dignity appeared to be a determinant of greater awareness of rights, it did not lead to increased empowerment with regard to rights. The availability of and access to sexual and reproductive health services remains a problem and displaced populations continue to have little or no power to hold their authorities accountable.  相似文献   
984.
Analyses of commercially available wines suggested non-Brettanomyces sources of 4-ethylphenol and 4-ethylguaiacol. Grapes, enological additions, exposure to plastics, and oak-barrel aging were potential inputs considered. Investigations of whole grape bunch samples from two major red wine Vitis vinifera cultivars (L. cv. Cabernet Franc and Pinot Noir), a commercial mannoprotein additive, and three commercial enological tannin additions indicated they are not likely significant sources of these compounds. Studies on 15 commercial oak barrelled red wines from six Vitis vinifera cultivars (L. cv. Cabernet Franc, Cabernet Sauvignon, Dunkelfelder, Merlot, Pinot Meunier, and Pinot Noir), and a review of volatile phenol extraction from toasted oak wood, suggested that oak-aging may produce concentrations of up to 50 μg L?1 4-ethylphenol and 4-ethylguaiacol. Thus, following potential Brettanomyces-sourced aroma impacts in wine using 4-ethylphenol and/or 4-ethylguaiacol concentrations as proxies should only be considered reliable at analyte levels > 100 μg L?1. A review of worldwide 4-ethylphenol and 4-ethylguaiacol concentrations in wine, consumption patterns, and available toxicological data also suggested that levels of 4-ethylphenol being observed in wines worldwide do not warrant concerns about acute or long-term effects. While little is known about the toxicology of 4-ethylguaiacol, it is unlikely that elevated concentrations will pose any health-related concerns.  相似文献   
985.
The concentration of six HMs (Cd, Cr, Co, Pb, Hg and Ni) was analysed in 321 organically grown winter and spring wheat genotypes from six genotype groups, i.e. selections, old landraces, primitive wheat, spelt, old cultivars and cultivars. Also the potential risk of individual toxic HM to human health was estimated by using the Hazard Quotient (HQ). Significantly the lowest grain concentration of Cd was found in primitive wheat as compared to all other investigated genotype groups. Intake of HM by consumption of whole wheat grain was not found to pose a health risk to human for any of the investigated genotype groups. The bio-concentration factor of Cd for the different genotype groups indicated a lower ability to accumulate Cd for primitive wheat as compared to other genotype groups. The primitive wheat was found the most promising and might be of interest in future wheat breeding programs to develop wheat genotypes with low HMs concentration in the grain.  相似文献   
986.
Within the framework of research concerning the application of techniques alternative to chemical pesticides for control of parasites, the C.R.A. Experimental Institute for Olive Growing for many years has been performing a large investigation in order to detect sources of genetic resistance in olive germplasm. In the present study we observed the behavior related to the olive fly (Bactrocera oleae) infestation and Camarosporium dalmaticum infection of ten olive cultivars farmed under the same agronomic and climatic conditions in Calabria, Southern Italy. The sampling and the data collecting were carried out in three different ripening times.The drupe amount of oleuropein and cyanidine was detected by laboratory analyses in order to verify a possible correlation between these molecules and the level of infestation/infection of the above-mentioned parasites. The obtained data were submitted to analysis of variance. In relation to the fungal infection the results displayed that cvs Tonda nera dolce showed the lowest susceptibility, while the cv Giarraffa turned out to be the most susceptible. The less susceptible cultivars to the phytophagous were Tonda nera dolce and Bhardi Tirana. Since the less susceptible cultivar to olive fly attacks are the same observed in relation to the susceptibility to olive fruit rot, it is suggested a relation between the olive fly infestation and the fungal infection. It suggests the utility to achieve these results both to transfer directly to the farmers' world and to emphasize ecosystem health and biodiversity conservation.  相似文献   
987.
The volume of industrial and domestic wastewater is increasing significantly year by year with the change in the lifestyle based on mass consumption and mass disposal brought about by the dramatic development of economies and industries. Therefore, effective advanced wastewater treatment is required because wastewater contains a variety of constituents such as particles, organic materials, and emulsion depending on the resource. However, residual chemicals that remain during the treatment of wastewaters form a variety of known and unknown by-products through reactions between the chemicals and some pollutants. Chronic exposure to these by-products or residual chemicals through the ingestion of drinking water, inhalation and dermal contact during regular indoor activities (e.g., showering, bathing, cooking) may pose cancer and non-cancer risks to human health. For example, residual aluminium salts in treated water may cause Alzheimer's disease (AD). As for carbon nanotubes (CNTs), despite their potential impacts on human health and the environment having been receiving more and more attention in the recent past, existing information on the toxicity of CNTs in drinking water is limited with many open questions. Furthermore, though general topics on the human health impacts of traditional water treatment chemicals have been studied, no comparative analysis has been done. Therefore, a qualitative comparison of the human health effects of both residual CNTs and traditional water treatment chemicals is given in this paper. In addition, it is also important to cover and compare the human health effects of CNTs to those of traditional water treatment chemicals together in one review because they are both used for water treatment and purification.  相似文献   
988.
基于耦合关系的中国区域土地利用效益水平测度   总被引:3,自引:0,他引:3  
新时期,土地利用的属性决定了土地利用能同时产生社会经济效益与生态环境效益,而这两种效益的交互耦合进一步决定了土地利用的整体效益。本研究建立了土地利用的社会经济效益与生态环境效益的耦合模型,设计了分别测度这两种效益的指标体系,用熵值赋权法计算了各指标的权重,进而计算了中国31个省(市、自治区)土地利用中这两种效益的系数及其耦合协调发展系数。结果显示:第一类地区是我国社会经济与生态环境均较好的上海市;第二类地区主要是社会经济发展较好但生态环境建设相对滞后的地区;第三类是生态环境较好但社会经济发展相对滞后的地区;第四类是社会经济发展相对滞后但生态环境建设更为落后的地区;第五类是生态环境建设滞后但社会经济发展更为落后的地区。最后,对每一个类型的成因和未来发展思路作了说明,在此基础上,又说明了中国土地利用的整体效益仍较为有限、整体效益表现出较为明显的区域分布特征、社会经济与生态环境的协调发展已成为提高我国土地利用效益的现实选择等基本政策含义。  相似文献   
989.
从加油站作业人员接触的主要职业病危害因素入手,重点对加油站油气防护设施、个人防护用品、工作制度等进行职业卫生现场调查,同时,根据对作业人员职业性健康检查结果和作业场所空气中汽油及苯的浓度检测结果,分析加油站作业人员的健康状况和长期接触成品汽油对作业人员健康的影响。结果表明,加油站人员作业过程中接触的汽油及苯系物对员工健康可能构成危害,但若加强职业健康监护及个体防护,就能有效预防汽油及苯系物所带来的职业危害。  相似文献   
990.
我国目前在区域环境质量评价方面存在一定缺陷,常规评价指标无法表征特征污染物对区域生态环境及人体健康造成的暴露风险。以环境暴露风险理论为基础,对大黄堡湿地自然保护区内的大气、水及土壤构建复合环境要素综合评价模型,评价结果显示保护区的综合判别值为12.68×10-5 a-1,高于国际辐射防护委员会(ICRP)推荐的最大可接受值1.0×10-5 a-1,且地域差异比较明显,其中保护区北部农药厂周边地区潜在健康风险最高、东八里庄附近次之、而后蒲棒村周边相对较小。最终根据评估区域内环境暴露风险评价结果提出具有针对性的防范和治理措施,为保护区环境暴露风险的预警和管理提供决策依据。  相似文献   
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