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381.
Understanding why people make the decisions they do remains a fundamental challenge facing conservation science. Ecosystem service (ES) (a benefit people derive from an ecosystem) approaches to conservation reflect efforts to anticipate people's preferences and influence their environmental behavior. Yet, the design of ES approaches seldom includes psychological theories of human behavior. We sought to alleviate this omission by applying a psychological theory of human values to a cross‐cultural ES assessment. We used interviews and focus groups with fish workers from 28 coral reef fishing communities in 4 countries to qualitatively identify the motivations (i.e., human values) underlying preferences for ES; quantitatively evaluate resource user ES priorities; and identify common patterns among ES motivations and ES priorities (i.e., trade‐offs and synergies). Three key findings are evident that align with human values theory. First, motivations underlying preferences for individual ESs reflected multiple human values within the same value domain (e.g., self‐enhancement). Second, when averaged at community or country scales, the order of ES priorities was consistent. However, the order belied significant variation that existed among individuals. Third, in line with human values theory, ESs related to one another in a consistent pattern; certain service pairs reflected trade‐off relationships (e.g., supporting and provisioning), whereas other service pairs reflected synergistic relationships (e.g., supporting and regulating). Together, these findings help improve understanding of when and why convergence and trade‐offs in people's preferences for ESs occur, and this knowledge can inform the development of suitable conservation actions.  相似文献   
382.
We studied the effects of ecological variables on the birth sex ratio of Soay sheep (Ovis aries) lambs on the island of Hirta, in the St Kilda archipelago, Scotland. Both individual- and population-level models were constructed. In the individual-based model, only population size was significantly associated with the sex of a lamb, with the probability of giving birth to a male lamb being positively associated with population size. However, this model explained a very small proportion of the variance in birth sex ratio. A multiple regression analysis of the annual population birth sex ratio also showed a slight increase in the proportion of males born in years following high autumn population density, but this result was not statistically significant. Population growth rate, Julian birthday, litter size, mother's age and weight, and the weather conditions during the gestation and neonatal period did not explain significant variation in the birth sex ratio.  相似文献   
383.
Crafting Effective Solutions to the Large Carnivore Conservation Problem   总被引:3,自引:0,他引:3  
How problems are defined and redefined largely dictates how they will (or if they can) be solved, especially complex problems such as the challenge of conserving large carnivores in North America. We describe a practical and comprehensive method for analyzing problems within specific human and ecological contexts and for inventing, evaluating, and selecting solutions. We conducted a problem definition exercise for the large carnivore conservation problem and arrived at five key variables that must be addressed in order to protect these threatened species: cultural history, valuation, ecology, management systems, and the policy process. Our analysis maps the broad dimensions of the problem and identifies areas to be targeted by any successful solution strategy. The method we present and our proposed initial definition of the carnivore conservation problem can serve as a springboard for further analysis and policy making at specific sites and at appropriate scales for on-the-ground solutions to this and other natural resource problems.  相似文献   
384.
Large-scale exploitation of fossil fuels and nuclear power can have an adverse effect on the human and natural environment. That need not be the case, if the effect on the environment is carefully assessed to ensure the development of a sustainable approach. This paper examines the process of environmental impact assessment (EIA) for coal from an international perspective. The concept of EIA is not new. A formalized process of EIA was introduced in the USA in 1970, and more recently similar legislation has been implemented in other countries. The member states of the European Community are required to adopt EIA regulations, as set out in Directive 85/337/EEC. Elsewhere, in Japan and Australia, there are requirements for EIA and a growing need for the process can be seen in developing countries. A comparison is made of the EIA process for coal in the international arena, and exemplary procedures are highlighted. Potential problems such as delays, modifications and additional costs are analysed, and the benefits of EIA, both to industry and environment, are discussed. A database of coal-related EIA would facilitate an exchange of information on the subject.  相似文献   
385.
This article summarizes a research project that investigated the use, performance, cost, and evaluation of nonstructural measures to improve urban stormwater quality. A survey of urban stormwater managers from Australia, New Zealand, and the United States revealed a widespread trend of increasing use of nonstructural measures among leading stormwater management agencies, with at least 76% of 41 types of nonstructural measures being found to be increasing in use. Data gathered from the survey, an international literature review, and a multicriteria analysis highlighted four nonstructural measures of greatest potential value: mandatory town planning controls that promote the adoption of low-impact development principles and techniques; development of strategic urban stormwater management plans for a city, shire, or catchment; stormwater management measures and programs for construction/building sites; and stormwater management activities related to municipal maintenance operations such as maintenance of the stormwater drainage network and manual litter collections. Knowledge gained on the use and performance of nonstructural measures from the survey, literature review, and three trial evaluation projects was used to develop tailored monitoring and evaluation guidelines for these types of measure. These guidelines incorporate a new evaluation framework based on seven alternative styles of evaluation that range from simply monitoring whether a nonstructural measure has been fully implemented to monitoring its impact on waterway health. This research helps to build the stormwater management industry’s knowledge base concerning nonstructural measures and provides a practical tool to address common impediments associated with monitoring and evaluating the performance and cost of these measures.  相似文献   
386.
In recent years, the debate on corporate responsibility has shifted from a focus on environmental management towards a broader concept of corporate social responsibility (CSR). This article examines the chemical industry's approach to CSR from the perspective of two emerging economies: Mexico and South Africa. The global chemical industry was one of the first to respond to public concerns about environmental pollution, toxic waste and human health by adopting an industry‐wide code of practice, known as Responsible Care. This article examines the extent to which the chemical industry has responded to the broader debate on CSR. On the basis of a comparative case study, this article argues that the response to social issues by Mexican and South African chemical companies has tended to be limited to the ‘community awareness and emergency response’ (CAER) or community dialogue component of the international voluntary management framework, Responsible Care. Similarities and differences in regulatory and institutional conditions, as well as different levels of civil society engagement, reveal additional limitations for CSR, beyond that of the Responsible Care framework. This article argues that the socio‐political context influences the extent to which companies embrace CSR, especially in emerging economies, and highlights several challenges for the chemical industry in moving forward on CSR: credibility, stakeholder engagement, value‐chain accountability, disclosure and transparency. Reflecting on these challenges, the authors conclude by recommending a renewed focus on: (1) developing a broader set of CSR management practices beyond Responsible Care; (2) institutionalizing stronger accountability measures, such as reporting and verification; and (3) developing multi‐stakeholder partnerships that complement regulation and build public sector regulatory and guidance capacity.  相似文献   
387.
The terrestrial chapter of the Circumpolar Biodiversity Monitoring Programme (CBMP) has the potential to bring international multi-taxon, long-term monitoring together, but detailed fundamental species information for Arctic arthropods lags far behind that for vertebrates and plants. In this paper, we demonstrate this major challenge to the CBMP by focussing on spiders (Order: Araneae) as an example group. We collate available circumpolar data on the distribution of spiders and highlight the current monitoring opportunities and identify the key knowledge gaps to address before monitoring can become efficient. We found spider data to be more complete than data for other taxa, but still variable in quality and availability between Arctic regions, highlighting the need for greater international co-operation for baseline studies and data sharing. There is also a dearth of long-term datasets for spiders and other arthropod groups from which to assess status and trends of biodiversity. Therefore, baseline studies should be conducted at all monitoring stations and we make recommendations for the development of the CBMP in relation to terrestrial arthropods more generally.  相似文献   
388.
Juhasz AL  Smith E  Weber J  Rees M  Rofe A  Kuchel T  Sansom L  Naidu R 《Chemosphere》2008,71(10):1963-1969
Considerable information is available in the literature regarding the uptake of arsenic (As) from contaminated soil and irrigation water by vegetables. However, few studies have investigated As speciation in these crops while a dearth of information is available on As bioavailability following their consumption. In this study, the concentration and speciation of As in chard, radish, lettuce and mung beans was determined following hydroponic growth of the vegetables using As-contaminated water. In addition, As bioavailability was assessed using an in vivo swine feeding assay. While As concentrations ranged from 3.0 to 84.2mg As kg(-1) (dry weight), only inorganic As (arsenite and arsenate) was detected in the edible portions of the vegetables. When As bioavailability was assessed through monitoring blood plasma As concentrations following swine consumption of As-contaminated vegetables, between 50% and 100% of the administered As dose was absorbed and entered systemic circulation. Arsenic bioavailability decreased in the order mung beans>radish>lettuce=chard.  相似文献   
389.
390.
In several primates, the presence of mothers affects the growth, survival and reproduction of their offspring, but similar effects have not yet been demonstrated in ungulates. Here, we investigate the effects of the mother’s presence in a population of red deer (Cervus elaphus) on the Isle of Rum, Scotland, which is the subject of a long-term, individual-based study. We compared measures of performance including antler growth in young males and age at first reproduction in females and survival of deer with mothers still alive against those that have lost their mothers (orphans). We show that orphaning both before and after weaning increases the risk of a natural death for both sexes. For males, no maternal benefit was detectable past 24 months of age while, for females, post-weaning benefits continued throughout life. Orphaning resulted in compromised male physical condition as measured by a reduced probability of growing antlers by 16 months of age while no evidence for compromised reproduction was found in females. These results support assertions that post-weaning maternal associations affect the development and survival of offspring.  相似文献   
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