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41.
根据2006年5月~2007年5月逐月采集青岛沙子口近海作业的定置网具渔获物的分析与测定,记述了该海区出现的98种渔业生物,并进行了定置网渔获物组成的分析,分析了种类组成特点及生物多样性的季节变化情况.结果表明,本调查区域渔获物以小型低值鱼类、经济无脊椎动物和经济幼鱼为主,渔获个体偏小.据此提出了保护近海生物多样性与合理利用近海渔业资源的一些建议.  相似文献   
42.
甲维盐属高效半合成抗生素杀虫剂。在哈尔滨市典型黑土农田区,研究不同浓度甲维盐处理对土壤动物群落结构的影响。结果表明:甲维盐处理显著降低了土壤动物群落的个体密度和类群数量,且这种趋势随着甲维盐浓度的增加而增强;显著改变了群落的垂直分布格局,表聚性特征被削弱,使动物较多地聚集于5~15 cm土层;改变了群落多样性特征,其中螨类和跳虫对多样性的贡献相对较大;显著改变了表层土壤化学性质,但不同动物类群对土壤环境变化的响应规律不同,螨类和跳虫对甲维盐干扰具有较强的适应能力。甲维盐处理可以显著改变黑土区农田土壤动物群落结构,浓度是影响该过程的重要因素,施用杀虫剂时需慎重评价其生态后果。  相似文献   
43.
探讨了北京市海淀区翠湖国家城市湿地公园的水域生物多样性及保护方法,论证了生物防治藻类、高等植被恢复等基于物质循环再生原理的方法对水域生物多样性恢复的效果。实践表明,人工湿地污水净水系统、以营养环节来控制水体富营养化的生物水体防治方法,对翠湖湿地的水质有明显的净化、保护和提升作用,对水域生物多样性的保护起到了积极的作用。  相似文献   
44.
In September 2010, a Nature Index giving information on status and trends in biodiversity in nine larger ecosystems in Norway was presented. In the article, the authors ask how Norwegian youth politicians framed, i.e. articulated, the topic of biodiversity after being introduced to this new information. To answer this question, focus group interviews were conducted with leading youth politicians in the six largest political parties in Norway. A first finding was that knowledge of and interest in biodiversity at the outset was relatively low. In general, the interviews were structured along three dimensions. First, there was a general discussion about nature and biodiversity. Second, biodiversity was discussed in a political context in terms of state versus market, and local versus national and international politics. Finally, the role of science was discussed. In general terms, the study found that biodiversity as an issue is only to a limited extent able to influence established political opinions (no resonance), but is itself adapted to fit established ideologies (master frames).  相似文献   
45.
The Norwegian Nature Index is a comprehensive effort to ‘make nature visible’ in communications between policymakers and the general public. To ensure that appropriate ‘early warnings’ for biodiversity loss are made available as a basis for precautionary approaches to sustainability and biodiversity policy, different knowledge sources need to be applied, such as the Red List for threatened species and the Nature Index, which gives a comprehensive overview of biodiversity. The article shows how the Nature Index can be supplemented with ‘early warnings’ of biodiversity from involved scientific experts, who were asked to assess the situation in 2020 for the indicators, in view of all available knowledge. They also assessed the uncertainty in their forecasts and their considerations of the need for and difficulty of implementing management measures to maintain biodiversity at the current level. Particularly for the major ecosystems considered to have a poor state, namely forests and open lowlands, experts indicated that urgent action was needed to improve the state of many indicators and that such management action would be possible. The findings indicate potential for eliciting experts' formal and informal knowledge in assessing the need and potential approaches to biodiversity policy.  相似文献   
46.
Loss of biological diversity is among the most pressing environmental problems facing modern societies. Whereas today much is known about peoples' opinions on climate change, there is still a lack of knowledge regarding how people asses the issue of biological diversity. The article represents a step towards a better understanding of public opinions on the issue of biodiversity, and hence also of the prerequisites and possibilities for a more or less vigorous or legitimate policy on this issue. The analyses show that social background matters for concern about biodiversity, but only to a certain extent: women are less negative towards biodiversity protection than men, the older segments of the population, at least in Norway, are less concerned with biodiversity, and education has only a marginal effect. Hence, to a large extent, political attitudes matter and indicate that concern for biodiversity seems to work by various types of available heuristics whereby a given case is linked to political understandings of other and similar and/or familiar issues. The inclusion of other political variables (local decision-making) and what the authors label ‘cultural variables’ (e.g. view of nature and trust in science) seem also to matter decisively for attitudes towards biodiversity.  相似文献   
47.
The authors reflect on knowledge-generating and communication processes involved in the recently developed Norwegian Nature Index, particularly the communication process among experts involved in providing the required biodiversity knowledge. Eliciting a comprehensive overview of biodiversity is a complex process involving choices of approaches and methods in order to reach a common understanding of uncertainties and values as a basis for quantification. Part of the complexity is the establishment of dialogue between experts from research institutions with different research traditions and approaches. The authors discuss how the index was developed through communication processes, challenging involved experts to provide not only biodiversity data for the current situation, but also forecasts of future trends, assessments of uncertainty, and evaluations of the urgency of biodiversity loss and possibility of implementing policy and management measures. The Nature Index framework has potential for informing the biodiversity policy debate by involving stakeholders beyond the science-policy community and enhancing deliberations about biodiversity policy in a wider context of sustainable development. As a policy tool, the Nature Index may develop through a process of practical application, which in turn may have an impact on the selection of narratives, definition of management targets, and technical concepts such as reference states.  相似文献   
48.
The aim of the paper is to sum up knowledge of colour infrared (CIR) aerial photography as a tool for vegetation data for mapping and monitoring in environmental and biodiversity surveys and change detection surveillance. It compiles thirty years of research of the main ecosystems in Swedish vegetation, where the overall goal was to develop methods for mapping and monitoring vegetation by use of CIR aerial photographs, assess the accuracy compared to field-based mapping and to implement them as a tool in nature conservation and environmental planning. The methods include development of a classification system, identification and analysis of indicators, development of interpretation techniques, and evaluation compared to the data collected in the field. The CIR observable criteria are colour, texture, pattern, size, form, and density, based on spectral reflectance, physiognomy, life forms, ecological conditions, moisture and nutrition, vegetation period and phenology, topography, site conditions, and management methods. The methods have been used to produce vegetation maps of mountains, boreal forests, and mires in northern and central Sweden, in national inventories of wetlands, ancient meadows and pastures, key biotopes in forests and for monitoring agricultural landscapes.  相似文献   
49.
当代生物多样性剧减与古-中生代之交生物绝灭的对比   总被引:1,自引:0,他引:1  
何卫红  殷鸿福  盛桂莲  周修高 《地球科学》2004,29(3):263-268,316
18世纪以来人类活动对环境造成了强烈破坏,给生物多样性带来了巨大损失.为了了解生物多样性的变化趋势,利用"绝灭物种统计法"、"种-区曲线法"和化石记录对400年以来的生物多样性和古-中生代之交的生物绝灭进行了分析.当代生物多样性剧减表现为物种的快速绝灭(从8×104种/Ma增大到1.2×106种/Ma),而属的绝灭几乎为0;古-中生代之交生物绝灭的初始阶段也表现为物种的快速绝灭(从40种/Ma增大到150种/Ma),并且这个阶段的属的绝灭速率远低于绝灭高峰阶段的相应值(即66属/Ma远小于465属/Ma),可见当代生物多样性剧减相当于二叠-三叠系之交生物绝灭的初始阶段.  相似文献   
50.
ABSTRACT

The Australian government’s proposal to expand the Snowy Hydro Scheme to include a second pumped hydro energy storage (PHES) system, and support for feasibility studies for PHES in Tasmania, offer an opportunity to incorporate more intermittent renewable energy generation into the National Energy Market. However, the infrastructure construction required for PHES expansion may have negative effects for biodiversity in subalpine and alpine areas. To identify the potential effects of PHES on biodiversity in Kosciuszko National Park (KNP), this systematic literature review assesses: (i) the key environmental disturbances likely to arise from PHES construction; and (ii) the specific impacts of these construction processes on biodiversity in subalpine and alpine environments. We find that the effects of PHES construction-related disturbances are likely to be negative for subalpine and alpine biodiversity, with impacts including the proliferation of exotic flora, habitat loss resulting from vegetation clearing, altered landscape hydrology and reduced water quality. Management recommendations to limit these impacts are provided and further research is recommended to assess: (i) the effects of PHES on fish populations in alpine reservoirs; (ii) the utility of spoil as artificial habitat for endemic fauna; and (iii) the chemical and physical impacts of spoil dumping in alpine reservoirs.  相似文献   
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