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201.
BACKGROUND: Triggered by the requirement of Water Framework Directive for a good ecological status for European river systems till 2015 and by still existing lacks in tools for cause identification of insufficient ecological status MODELKEY (http:// www.modelkey.org), an Integrated Project with 26 partners from 14 European countries, was started in 2005. MODELKEY is the acronym for 'Models for assessing and forecasting the impact of environmental key pollutants on freshwater and marine ecosystems and biodiversity'. The project is funded by the European Commission within the Sixth Framework Programme. OBJECTIVES: MODELKEY comprises a multidisciplinary approach aiming at developing interlinked tools for an enhanced understanding of cause-effect-relationships between insufficient ecological status and environmental pollution as causative factor and for the assessment and forecasting of the risks of key pollutants on fresh water and marine ecosystems at a river basin and adjacent marine environment scale. New modelling tools for risk assessment including generic exposure assessment models, mechanistic models of toxic effects in simplified food chains, integrated diagnostic effect models based on community patterns, predictive component effect models applying artificial neural networks and GIS-based analysis of integrated risk indexes will be developed and linked to a user-friendly decision support system for the prioritisation of risks, contamination sources and contaminated sites. APPROACH: Modelling will be closely interlinked with extensive laboratory and field investigations. Early warning strategies on the basis of sub-lethal effects in vitro and in vivo are provided and combined with fractionation and analytical tools for effect-directed analysis of key toxicants. Integrated assessment of exposure and effects on biofilms, invertebrate and fish communities linking chemical analysis in water, sediment and biota with in vitro, in vivo and community level effect analysis is designed to provide data and conceptual understanding for risk arising from key toxicants in aquatic ecosystems and will be used for verification of various modelling approaches. CONCLUSION AND PERSPECTIVE: The developed tools will be verified in case studies representing European key areas including Mediterranean, Western and Central European river basins. An end-user-directed decision support system will be provided for cost-effective tool selection and appropriate risk and site prioritisation.  相似文献   
202.
Abstract:  The rainforests of the Amazon basin are being cut by humans at a rate >20,000 km2/year, leading to smaller and more isolated patches of forest, with remaining fragments often in the range of 1–100 ha. We analyzed samples of understory birds collected over 20 years from a standardized mist-netting program in 1– to 100-ha rainforest fragments in a dynamic Amazonian landscape near Manaus, Brazil. Across bird guilds, the condition of second growth immediately surrounding fragments was often as important as fragment size or local forest cover in explaining variation in abundance. Some fragments surrounded by 100 m of open pasture showed reductions in insectivorous bird abundance of over 95%, even in landscapes dominated by continuous forest and old second growth. These extreme reductions may be typical throughout Amazonia in small (≤10 ha), isolated fragments of rainforest. Abundance for some guilds returned to preisolation levels in 10- and 100-ha fragments connected to continuous forest by 20-year-old second growth. Our results show that the consequences of Amazonian forest loss cannot be accurately described without explicit consideration of vegetation dynamics in matrix habitat. Any dichotomous classification of the landscape into "forest" and "nonforest" misses essential information about the matrix.  相似文献   
203.
The paper presents an evaluation of post-project impacts of the Barekese Dam on three riparian communities downstream about 30 years after its construction. A network diagram, which incorporated a mathematical model, was used for impact identification and analysis. The expected environmental impacts, expressed as quantitative weighted impact scores, showed that the dam appeared to have exerted adverse impacts on the environmental quality of the communities. The impacts in the communities, however, increased with relative distances away from the dam and the river suggestive of cumulative impacts transmitted downstream. Strategic measures for improving environmental quality of the communities have been given.  相似文献   
204.
为了探讨南淝河不同河段沉积物细菌群落结构特征差异及其主要驱动因素,在对南淝河不同土地利用区域河段表层沉积物的主要理化指标(pH、CEC、TOC、DOC、氮分级形态)进行分析基础上,重点通过MiSeq高通量测序技术对沉积物中细菌群落结构特征进行了分析,并利用冗余分析(RDA)方法探讨了导致群落结构差异的主要驱动因素.结果表明:沉积物中门水平下优势细菌种群为变形菌门(Proteobacteria)、绿弯菌门(Chloroflexi)和拟杆菌门(Bacteroidetes);纲水平下除未分类外主要是厌氧绳菌纲(Anaerolineae)、γ-变形菌纲(Gammaproteobacteria)、梭状芽胞杆菌纲(Clostridia)、δ-变形菌纲(Deltaproteobacteria),此外ε-变形菌纲(Epsilonproteobacteria)主要在南淝河下游采样点被检测到,说明其在南淝河沉积物生态系统中并不是普遍存在的;属水平下大多为未分类序列,长绳菌属(Longilinea)和芽孢杆菌属(Bellilinea)有优势地位.南淝河不同河段所在流域土地利用方式不同会导致污染物类型、污染源强和沉积物理化指标的不同,进而影响沉积物细菌群落结构,中游城区和工业区段的细菌多样性整体上高于上、下游;RDA分析结果表明,表层沉积物的CEC、TOC、DOC、TP、WAEF-N和IEF-N是导致细菌群落结构特征差异的主要影响因子,其中变形菌门、拟杆菌门和厚壁菌门受TP影响较大,绿弯菌门则受弱酸浸取态氮(WAEF-N)影响较大.  相似文献   
205.
Social sciences’ research on the social acceptance of renewable energy generation and associated technologies (RET), such as high voltage power lines, has been growing in the last decades. In fact, while RET are considered one of the main mitigation measures of climate change, opposition to their construction, and namely from the local communities living nearby, is often found. Important conceptual proposals have been made for a better understanding of opposition, however, this literature still presents some limitations. Here, I will discuss two of them: first, the main focus on the local and, with it, the lack of a relational and critical approach, which recognizes opposition and other types of responses to RET as public participation in RET-related issues; second, the focus on the individual and the consequent lack of examining people’s material practices and engagements.  相似文献   
206.
藓类附生原生动物群落对汞铊矿重金属污染的监测   总被引:1,自引:0,他引:1  
应用群落多样性特征指数和冗余分析法(RDA),对黔西南滥木厂汞铊矿的矿渣、废石、矿体和附近的石灰岩上的藓类附生原生动物与重金属污染的关系进行研究.经显微镜检,共发现藓类附生原生动物群落物种数为75种,原生动物丰度范围在2~504个.g-1.群落多样性指数结果表明,矿渣的重金属污染最严重.RDA分析结果表明,重金属污染对藓类附生原生动物群落结构变化有明显的影响,有些种类对重金属污染十分敏感或有一定的耐性.因此,藓类附生原生动物群落可用来监测矿区生态系统的重金属污染.  相似文献   
207.
Ecological literacy is founded upon knowledge and understanding about how the ecological systems of the Earth function and support life. A widespread concern that levels of ecological literacy within many contemporary human communities are inadequate to enable effective decision-making about sustainable ways of living led to a rigorous and carefully designed assessment of over 1000 South Australian adults from diverse sectors including industry, government, nongovernment, business and community organisations. This assessment tested for local and global knowledge, including an understanding of the interconnection of natural systems with human society. Quantitative analyses revealed significant relationships between scores and a range of socio-demographic characteristics. Scores varied significantly with gender, age, education, employment, place of growing up and time spent in South Australia (SA). Highest average scores were found in males, middle-age groups, the most highly educated, those with science-related educational backgrounds, those working in environment-related fields, those who grew up in small town environments rather than in large towns or cities and in those who had spent more than 10 years in SA. These findings contribute to a broader study of factors associated with ecologically literate individuals and groups within the western and industrialised adult community of SA. They form a valuable foundation on which to build efforts to further understand and develop ecological literacy within our citizenry and governing bodies.  相似文献   
208.
ABSTRACT

This article draws from the author’s four-year study of five school communities hit by the 2010–2011 earthquake sequence in the Canterbury region of New Zealand to highlight the roles that schools played in supporting their communities in the aftermath of the disaster. The article begins by synthesising the relevant literature on disasters, schools in earthquake disasters, and the importance of schools to their communities, pre- and post-disaster. The following themes from the data are discussed: (a) the role of schools in their communities prior to the earthquakes; (b) the role of schools in immediate rescue and response; (c) the role of schools in short-term relief; and (d) the role of schools in long-term recovery. The author then argues that as more evidence shows that schools play such crucial roles in post-disaster response and recovery, we need to better prepare and support them to undertake these functions. Further, we need to recognise the wider roles schools play supporting local communities to build and sustain resilience as part of on-going community cohesion and connectedness, so that society is better prepared when major disasters occur.  相似文献   
209.
金沙江一期工程蓄水前后绥江段鱼类群落多样性特征   总被引:1,自引:0,他引:1  
为探索流域梯级水电开发对鱼类群落多样性影响,于2011年(蓄水前)和2015年(蓄水后)对金沙江下游绥江断面进行渔业资源调查,分析鱼类群落结构特征。结果表明,绥江段共计采集鱼类60种,隶属于5目12科,其中长江上游特有鱼类12种。蓄水前以瓦氏黄颡鱼(Pelteobagrus vachelli)、圆口铜鱼(Coreius guichenoti)、光泽黄颡鱼(Pelteobagrus nitidus)为优势种类;蓄水后以草鱼(Ctenopharyngodon idellus)、鳙(Aristichthys nobilis)、鲢(Hypophthalmichthys molitrix)为优势种类。与蓄水前相比,鱼类群落Margalef丰富度指数、Shannon-Weiner多样性指数、Pielou均匀度指数均呈现下降趋势,但无显著性差异(P0.05)。根据生态类群分析,静水缓流型鱼类由蓄水前54%增加到蓄水后的71%,河道洄游型鱼类从39%减少到20%,江湖洄游型鱼类蓄水前后变化不大。丰度生物量比较曲线显示,蓄水前绥江段鱼类群落未受到干扰,而蓄水后受到严重干扰。库区蓄水后总生物量有明显增加趋势,但优势种类趋于小型化、种类结构单一化。为科学保护金沙江下游流域鱼类生物多样性,建议成立鱼类保护区、开展梯级生态调度和加强流域环保预警研究等措施。  相似文献   
210.
ABSTRACT

This paper will examine three diverse microgrid cases in the US, Canada, and the European Union. The paper will explore how microgrids can help build resilient communities, facilitate distributed renewable energy, and ultimately lead to a secure energy future. The cases will include both urban and remote settings and compare the social, legal, and policy lessons learned from these cases to advance microgrid policy for long-term community resilience.  相似文献   
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