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351.
Designatable Units for Status Assessment of Endangered Species 总被引:8,自引:1,他引:8
DAVID M. GREEN 《Conservation biology》2005,19(6):1813-1820
Abstract: Species status assessment and the conservation of biological diversity may require defining units below the species level to portray probabilities of extinction accurately and to help set priorities for conservation efforts. What those units should be has been debated in the scientific literature largely in terms of evolutionarily significant units (ESUs), but this discourse has had little impact on government policy with regard to status assessment. As with species concepts, the variously proposed ESU concepts have not been resolvable into a single approach. The need for a practicable procedure to identify infraspecific entities for status assignment is the motivation behind employing designatable units (DUs). In aid of a policy to prevent elements of biodiversity from becoming extinct or extirpated, DUs are determined during the process of resolving a species' conservation status according to broadly applicable guidelines. The procedure asks whether putative DUs are distinguishable based on a reliably established taxonomy or a well-corroborated phylogeny, compelling evidence of genetic distinction, range disjunction, and/or biogeographic distinction as long as extinction probabilities also differ. The language of the DU approach avoids wording that implies value judgments concerning evolutionary importance or significance. Because species conservation status assessment is not science but, rather, the use of science to further policy, DUs contribute to a precautionary approach to listing whereby status may be assessed even though knowledge of systematic relationships below the species level may be lacking or unresolved. The pragmatic approach of using DUs has been adopted by the Committee on the Status of Endangered Wildlife in Canada for status assessment of species under the Canadian Species at Risk Act. 相似文献
352.
We studied sampling behaviour and mate choice in the fiddler crab Uca mjoebergi. Once a female selects a mate, she copulates in his burrow and remains there until releasing her aquatic larvae. U. mjoebergi occurs in habitats that are inundated only by the highest amplitude spring tides. Females can only release their larvae during
these tides, and release before or after will result in complete failure of reproductive effort. Matings occur over a 5-day
period near the end of neap tides. Our results suggest that within the mating period, females adjust their larval developmental
rates by selecting specific burrows in which to incubate their clutches. We found that at the start of the mating period,
females chose larger males as mates. Since male size was positively correlated to burrow width, females were selecting wide
burrows and effectively incubating at lower temperatures. This would slow down the developmental rates of larvae. In contrast,
females that mated late in the mating period selectively chose small males. By incubating in narrower, warmer burrows, these
females may increase the developmental rates of larvae. We propose that females are selecting burrows to influence incubation
rate and ensure timely release of their larvae. Female U. mjoebergi appear to adjust their preference for the direct benefits of mate choice to increase their reproductive success. 相似文献
353.
袁助人 《城市环境与城市生态》1996,9(3):42-47
辽宁中部城市群是由以沈阳为中心,包括沈阳,鞍山、抚顺、本溪、辽阳、铁岭六个市。本文分三部分,辽宁中部城市不境质量现状基本概况,辽宁中部城市九环境保护治理,辽宁中部城市群环境保护政策措施。 相似文献
354.
355.
356.
DANIEL C. NEPSTAD†‡ CLAUDIA M. STICKLER†§ ORIANA T. ALMEIDA† 《Conservation biology》2006,20(6):1595-1603
Abstract: Amazon beef and soybean industries, the primary drivers of Amazon deforestation, are increasingly responsive to economic signals emanating from around the world, such as those associated with bovine spongiform encephalopathy (BSE, "mad cow disease") outbreaks and China's economic growth. The expanding role of these economic "teleconnections" (coupled phenomena that take place in distant places on the planet) led to a 3-year period (2002–2004) of historically high deforestation rates. But it also increases the potential for large-scale conservation in the region as markets and finance institutions demand better environmental and social performance of beef and soy producers. Cattle ranchers and soy farmers who have generally opposed ambitious government regulations that require forest reserves on private property are realizing that good land stewardship—including compliance with legislation—may increase their access to expanding domestic and international markets and to credit and lower the risk of "losing" their land to agrarian reform. The realization of this potential depends on the successful negotiation of social and environmental performance criteria and an associated system of certification that are acceptable to both the industries and civil society. The foot-and-mouth eradication system, in which geographic zones win permission to export beef, may provide an important model for the design of a low-cost, peer-enforced, socioenvironmental certification system that becomes the mechanism by which beef and soy industries gain access to markets outside the Amazon. 相似文献
357.
Adaptation Options Strategies for Hazards and Vulnerability Mitigation: An International Perspective
C.?Emdad?HaqueEmail author Ian?Burton 《Mitigation and Adaptation Strategies for Global Change》2005,10(3):335-353
The broad objective of this special issue of Mitigation and Adaptation Strategies for Global Change is to address some of the gaps in our knowledge and understanding of the policies, programs, and measures that might be applied
to natural hazards and their impacts in an era of climate change. Given the global impacts of climate change and world-wide
pattern of increasing losses from natural hazards we necessarily adopt an international perspective. The specific goals of
the special issue are to: (a) encompass experiential aspects, emphasizing current practice of mitigation and its associated
measures, and their results; and (b) explore primary or root causes of alarming shifts in human and economic costs of environmental
extremes. Special emphasis is placed on how human activities are playing a key role in enhancing vulnerability to NTEE (nature-triggered
environmental extremes), quite independently from the anthropogenic causes of climate change. The goals are also (c) to examine
costs, risks, and benefits (of all kinds including social, political, ecological) of mitigation, and adjustment and adaptation
measures; and (d) analyze policy implications of alternative measures. These components are expected to make significant contributions
to policy considerations – formulation, implementation and evaluation. There is much uncertainty about the rate of climate
change; however, the fact of increase of the atmospheric temperature in the last century is no longer a subject of scientific
or policy debate. Due to such changes in the geophysical parameters, certain types of nature-triggered environmental extreme
events are likely to continue to increase. How global warming will affect regional climates and pertinent variables is not
well known, limiting our ability to predict consequential effects. This factor poses serious constraints against any straightforward
policy decisions. Research findings of the work of this volume reaffirm that human dimensions, specifically our awareness
and decision-making behavior, are powerful explanatory factors of increasing disaster losses. Disaster mitigation through
addressing human, social, and physical vulnerability is one of the best means for contributing to ‘climate change adaptation
plans’, and sustainable development goals. Recent lessons from various countries have depicted that the formulation of mitigation
strategies cannot be exclusively top-down as it requires social, political, and cultural acceptance and sense of ownership.
An interactive, participatory process, involving local communities, produces best expected outcomes concerning mitigation,
preparedness, and recovery. An emerging consensus is that there is a need to move towards the ‘mission’ of the International
Strategy for Disaster Reduction which aims at building disaster resilient communities by promoting increased awareness of
the importance of disaster reduction as an integral component of sustainable development, with the goal of reducing human,
social, economic and environmental losses due to natural hazards and related technological and environmental disasters. Sharing
of best practices and lessons globally is certain to produce more efficiency and understanding in policy and decision making. 相似文献
358.
Amanda Machin 《环境政策》2019,28(2):208-227
ABSTRACTOver the last three decades, ecological modernisation (EM) has emerged as a powerful political discourse, in which economic growth, environmental protection and energy security are mutually reinforcing. Here, the trajectory of EM in the European Union is traced, using a discourse analysis of the seven Environmental Action Programmes. The discourse articulated in these documents points towards an encroaching ‘double depoliticisation’. First, political decisions are discursively constructed as a matter of market rationality rather than a democratic process that engages with different political positions. Second, EM is reified as the only feasible solution, and alternative and contesting discourses are marginalised. Thus not only are political differences erased from the discourse, but the discourse is itself removed from political debate. 相似文献
359.
Steinhäuser KG Richter S Greiner P Penning J Angrick M 《Environmental science and pollution research international》2004,11(5):284-290
BACKGROUND, AIM AND SCOPE: With respect to the enormous increase of chemical production in the last decades and the tens of thousands of individual chemicals on the market, the permanent improvement of chemical management is a permanent target to achieve the goals of sustainable consumption and production set by the WSSD in Johannesburg 2002. MAIN FEATURES: Several approaches exist to describe sustainability of chemistry. However, commonly agreed criteria are still missing. There is no doubt that products of modern chemistry help to achieve important goals of sustainability and that significant improvements have occurred regarding direct releases from production sites, but several facts demonstrate that chemistry is far from being sustainable. Still too many chemicals exhibit hazardous characteristics and pose a risk to health and environment. Too many resources are needed to produce chemicals and finished products. RESULTS AND CONCLUSION: Therefore, a strategy for sustainability of chemistry should be developed which comprises the following main elements: 1. Sustainable chemicals: sustainable chemical management includes a regulatory framework which makes no difference between new and existing chemicals, contains efficient information flow through the supply chain which allows users to handle chemicals safely and offers an authorisation procedure and/or an efficient restriction procedure for substances of high concern. This regulatory scheme should promote the development of inherently safe chemicals. 2. Sustainable chemical production: Sustainable chemical production needs the development and implementation of emerging alternative techniques like selective catalysis, biotechnology in order to release less CO2 and less toxic by-products, to save energy and to achieve higher yields. Information exchange on best available techniques (BAT) and best environmental practices (BEP) may help to promote changes towards more sustainability. 3. Sustainable products: An integrated product policy which provides a framework for sustainable products promotes the development of products with a long-term use phase, low resource demand in production and use, low emission of hazardous substances and properties suitable for reuse and recycling. This may be promoted by eco-labelling, chemical leasing concepts and extended information measures to enhance the demand of consumers and various actors in the supply chain for sustainable products. RECOMMENDATION AND PERSPECTIVE: Important tools for the promotion of sustainable chemistry are the abolition of barriers for innovation in legislation and within the chemical industry, more transparency for all users of chemical products, a new focus on sustainability in education and research, and a new way of thinking in terms of sustainability. 相似文献
360.
清洁发展机制项目运作关键问题分析与管理对策研究 总被引:1,自引:0,他引:1
清洁发展机制(CDM)项目要想能够顺利通过一系列审查并最终获得减排量,需要特别重视项目运作流程中的关键环节。针对中国CDM项目审批数量少,通过率低,耗费时间长等问题,本文在分析CDM内涵及项目运作流程的基础上,指出了中国CDM项目运作中面临的主要问题,提出了相应的管理对策与建议,期望能够为中国推进CDM项目实施提供帮助。 相似文献