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361.
Biodiversity and human well-being strategies are only as good as the set of ideas people think about. We evaluated value-focused thinking (VFT), a framework that emphasizes creating objectives and strategies that are responsive to the objectives. We performed a proof-of-concept study of VFT with 6 conservation planning teams at a global conservation organization. We developed a package of materials related to VFT, including meeting–session agendas, a virtual facilitation template, facilitator's guide, and evaluation questionnaires. We used these materials to test whether VFT applied in a group setting resulted in high-quality conservation strategies and participant satisfaction and whether our materials were scalable, meaning that someone newly trained in VFT could facilitate planning meetings that resulted in high-quality strategies and participant satisfaction, as compared with an experienced VFT facilitator. Net response indicated positive compelling, feasible, creative, and representative ratings for the conservation strategies per team. Participants indicated satisfaction overall, although satisfaction was greater for objectives than for strategies. Among the participants with previous conservation planning experience, all were at least as satisfied with their VFT strategies compared with previously developed strategies, and none were less satisfied (p = 0.001). Changes in participant satisfaction were not related to facilitator type (experienced or inexperienced with VFT) (p > 0.10). Some participants had a preconceived sense of shared understanding of important values and interests before participating in the study, which VFT strengthened. Our results highlight the advantages of structuring the development and evaluation of conservation planning frameworks around VFT.  相似文献   
362.
From an environmental perspective, the media have raised the level of environmental awareness and, rightly or wrongly, focused the attention of citizens on specific environmental issues. Public reaction to environmental news can filter back into the media and highlight specific policy issues. The importance of the media in this respect has gained strength, particularly in developing countries, where environmental problems have become legitimate concerns, and where access to 'official' information has been historically difficult. In general, newspapers have been found to be one of the most predominant sources of environmental information available to the public, particularly in developing countries. In this paper, we summarise, briefly analyse and compare the newspaper coverage of environmental issues in Argentina, Chile, Mexico and the Philippines. Among numerous other results, it appears that the coverage of environmental issues fell considerably over the period 1990-94 despite an increase in world-wide environmental awareness. Most news reports actions by the environmental agencies (warnings and rewards, etc.). In the Philippines, however, most environmental news reports investments in pollution abatement activities by the private sector. While citizens' complaints represent a small percentage of the coverage of environmental issues, closer examination reveals that such complaints, in the vast majority of cases, trigger governmental actions (warnings) and ultimately an improvement of firms' environmental performance (investment).  相似文献   
363.
Benthic marine primary producers affect the chemistry of their surrounding environment through metabolic processes. Photosynthesis and respiration will elevate or depress the concentration of oxygen in the diffusive boundary layer. Likewise, acid–base regulation and biomineralization/dissolution for calcifying species can alter the relative concentration of inorganic carbon species and thus pH. Here, we measured the relative ability of several common benthic primary producers from coral reef systems of the central Pacific and the Caribbean to simultaneously affect seawater oxygen concentration and pH values. Repeated measurements over a diel cycle confirmed that several primary producers substantially alter surrounding seawater chemistry over time. The majority of fleshy algae exhibited a stoichiometric ratio of oxygen to hydrogen ions not significantly different from one during daylight hours. In contrast, calcifiers exhibited significantly lower oxygen to hydrogen ion ratios that were unique for each species and were inversely correlated with known rates of calcification. These data provide the first quantitative estimates of the simultaneous influence of several species of benthic primary producers on water column oxygen concentrations and pH across different tropical reef systems. Finally, because more productive fleshy taxa have the potential to raise both oxygen and pH during the day to a greater extent than calcified species, our results suggest that some fleshy taxa may provide a buffering capacity to future ocean acidification scenarios.  相似文献   
364.
The siting of hazardous waste facilities is complex, controversial, time-consuming, expensive, and sometimes impossible. Pressures for and against these facilities are immense. California is developing the “Tanner process,” a one-stop concept in which a single agency serves as the focal point (lead agency) for all the state institutions involved. In this paper I review the experience gained to date with the proposal for the largest liquid toxic waste incinerator proposed for California. I present positive and negative aspects of the process, and draw some policy conclusions. I explore a key policy goal: the search for win/win solutions such that both the community and industry come out ahead environmentally and economically. The experience, especially the approach to negotiation/discussion, is a model for possible use elsewhere in California and the nation.  相似文献   
365.
Ecosystem change often affects the structure of aquatic communities thereby regulating how much and by what pathways energy and critical nutrients flow through food webs. The availability of energy and essential nutrients to top predators such as seabirds that rely on resources near the water's surface will be affected by changes in pelagic prey abundance. Here, we present results from analysis of a 25-year data set documenting dietary change in a predatory seabird from the Laurentian Great Lakes. We reveal significant declines in trophic position and alterations in energy and nutrient flow over time. Temporal changes in seabird diet tracked decreases in pelagic prey fish abundance. As pelagic prey abundance declined, birds consumed less aquatic prey and more terrestrial food. This pattern was consistent across all five large lake ecosystems. Declines in prey fish abundance may have primarily been the result of predation by stocked piscivorous fishes, but other lake-specific factors were likely also important. Natural resource management activities can have unintended consequences for nontarget ecosystem components. Reductions in pelagic prey abundance have reduced the capacity of the Great Lakes to support the energetic requirements of surface-feeding seabirds. In an environment characterized by increasingly limited pelagic fish resources, they are being offered a Hobsonian choice: switch to less nutritious terrestrial prey or go hungry.  相似文献   
366.
Understanding how vulnerable forest ecosystems are to climate change is a key requirement if sustainable forest management is to be achieved. Modelling the response of species in their regeneration niche to phenological and biophysical processes that are directly influenced by climate is one method for achieving this understanding. A model was developed to investigate species resilience and vulnerability to climate change within its fundamental-regeneration niche. The utility of the developed model, tree and climate assessment (TACA), was tested within the interior Douglas-fir ecosystem in south-central British Columbia. TACA modelled the current potential tree species composition of the ecosystem with high accuracy and modelled significant responses amongst tree species to climate change. The response of individual species suggests that the studied ecosystem could transition to a new ecosystem over the next 100 years. TACA showed that it can be an effective tool for identifying species resilience and vulnerability to changes in climate within the most sensitive stage of development, the regeneration phase. The TACA model was able to identify the degree of change in phenological and biophysical variables that control tree establishment, growth and persistence. The response to changes in one or more of these variables resulted in changes in the climatic suitability of the ecosystem for species and enabled a measure of vulnerability to be quantified. TACA could be useful to forest managers as a decision support tool for adaptation actions and by researchers interested in modelling stand dynamics under climate change.  相似文献   
367.
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, a species extinction risk assessment tool, has been guiding conservation efforts for over 5 decades. It is widely assumed to have been instrumental in preventing species from moving closer to extinction and driving recoveries. However, the impact of the IUCN Red List in guiding conservation has not been evaluated. We conducted, transcribed, and coded interviews with experts who use the IUCN Red List across a range of sectors to understand how the list is used in conservation. We developed a theory of change to illustrate how and why change is expected to occur along causal pathways contributing to the long-term goal of the IUCN Red List and an evaluation framework with indicators for measuring the impact of the IUCN Red List in generating scientific knowledge, raising awareness among stakeholders, designating priority conservation sites, allocating funding and resources, influencing development of legislation and policy, and guiding targeted conservation action (key themes). Red-list assessments were the primary input leading to outputs (scientific knowledge, raised awareness), outcomes (better informed priority setting, access to funding and resource availability, improved legislation and policy), and impact (implemented conservation action leading to positive change) that have resulted in achievement of IUCN Red List goals. To explore feasibility of attributing the difference made by the IUCN Red List across themes, we studied increased scientific knowledge, raised awareness, access to funding and resource allocation, and increased conservation activity. The feasibility exploration showed increased scientific knowledge over time identified through positive trends in publications referring to the IUCN Red List in the literature; raised awareness of the list following high IUCN activity identified by peaks in online search activity; an increased proportion of conservation funding bodies requesting IUCN Red List status in the application process; and, based on interviews with Amphibian Specialist Group members, red-list assessments were essential in connecting relevant stakeholders and ensuring conservation action. Although we identified the IUCN Red List as a vital tool in global conservation efforts, it was challenging to measure specific impacts because of its ubiquitous nature. We are the first to identify the influence of the IUCN Red List on conservation.  相似文献   
368.
369.
A new in situ remediation concept termed a Horizontal Reactive Media Treatment Well (HRX Well®) is presented that utilizes a horizontal well filled with reactive media to passively treat contaminated groundwater in situ. The approach involves the use of a large‐diameter directionally drilled horizontal well filled with solid reactive media installed parallel to the direction of groundwater flow. The engineered contrast in hydraulic conductivity between the high in‐well reactive media and the ambient aquifer hydraulic conductivity results in the passive capture, treatment, and discharge back to the aquifer of proportionally large volumes of groundwater. Capture and treatment widths of up to tens of feet can be achieved for many aquifer settings, and reductions in downgradient concentrations and contaminant mass flux are nearly immediate. Many different types of solid‐phase reactive treatment media are already available (zero valent iron, granular activated carbon, biodegradable particulate organic matter, slow‐release oxidants, ion exchange resins, zeolite, apatite, etc.). Therefore, this concept could be used to address a wide range of contaminants. Laboratory and pilot‐scale test results and numerical flow and transport model simulations are presented that validate the concept. The HRX Well can access contaminants not accessible by conventional vertical drilling and requires no aboveground treatment or footprint and requires limited ongoing maintenance. A focused feasibility evaluation and alternatives analysis highlights the potential cost and sustainability advantages of the HRX Well compared to groundwater extraction and treatment systems or funnel and gate permeable reactive barrier technologies for long‐term plume treatment. This paper also presents considerations for design and implementation for a planned upcoming field installation.  相似文献   
370.
There has been an increase in scholarly attention to adolescents’ environmental attitudes; however, only a small number of empirical studies address the Adolescent Environmentalist’s (AE) personal and collective identity, media usage, and communication orientation. In this study, we investigate differences in young people (aged 12–17) who identify themselves as environmentalists, or the AEs, and those who do not drawing from a national sample of 1096 youth. Results show AEs significantly differ from their peers. The AEs have a different environmental value set, report greater self-confidence and influence among peers, support the stronger display of citizenship behaviors, follow certain news topics more, use and discuss the news more with a variety of others, and report engaging in more dialogue and persuasion.  相似文献   
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