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631.
The potential impacts of climate change are varied and highly uncertain, and pose a significant challenge to agencies charged with managing environmental risks. This paper presents a comprehensive and structured Mental Modeling approach to elicit, organize and present relevant information from experts and stakeholders about the factors influencing environmental risk management in the face of climate change. We present and review an initiative undertaken by the United States Army Corps of Engineers (USACE) to characterize climate change challenges to USACE environmental risk management activities, and to identify gaps with respect to science, engineering, and organizational processes for addressing these challenges. By employing Mental Modeling, the research has characterized the influences of climate change on USACE environmental risk management, and aggregating recommendations from 28 experts. In addition, the study identifies the most important opportunities to improve organizational response to climate change, ranging from focused research and development of technical capabilities to broad paradigm shifts and systemic organizational improvements within the USACE environmental risk management programs. This study demonstrates that Mental Modeling is a useful tool for understanding complex problems, identifying gaps, and formulating strategies, and can be used by a multitude of organizations and agencies.  相似文献   
632.
The announcement of plans for exploratory oil drilling at a number of offshore sites in Belize raised concerns about the risks associated with drilling, particularly given the socio‐economic importance of the marine ecosystem. The current economic value of fisheries and marine ecotourism is estimated, along with the potential revenue from offshore oil and potential economic losses stemming from oil pollution, under various assumptions on risk and uncertainty. Marine fisheries and ecotourism are estimated to generate around US$ 183 million per year. Single‐year estimated maximum revenue is higher for oil extraction initially but quickly declines; during a 50 year (two generation) period, total discounted benefits from marine fisheries and ecotourism are estimated at US$ 5.1 billion, compared to US$ 3.2 billion from offshore oil revenue. Following a hypothetical oil spill, discounted losses in marine fisheries and ecotourism due to perception and ecological impacts are estimated at US$ 912 million, with clean‐up costs and capital losses of US$ 6.1‐10.4 billion. Considering the short extraction life of oil resources compared to fisheries and ecotourism, the difference in benefits increases substantially in favour of the latter with a longer time horizon. A recent public referendum resulted in a 98% vote against oil exploration and a subsequent annulment of oil concessions pending environmental impact assessments.  相似文献   
633.
The impact of the extreme heat wave that affected Melbourne, Australia, in two distinct phases in January and February 2009 was severe, with 374 (heat) and 173 (bushfire) excess deaths. Whilst the human health issues have been covered in detail in policy and academic arenas, much less attention has been paid to the adverse impacts on urban infrastructure. Analysis of this event, underpinned by participatory actor-based research, has shown that the impacts were experienced disproportionately across different infrastructure types. For water, telecommunications and airports, the impacts were relatively minor and the impact on rail transport and roads (and to a lesser extent, seaports) was of moderate significance, whereas research findings indicate that the electricity sector was found to be the most vulnerable. This paper focuses on the sectors that were worst impacted: electricity, rail and road transport. Commentary identifies the direct and indirect impacts of the heat event, including associated cascading effects, as well as considering actual and potential adaptation responses both before and after the event. Concluding, the authors reflect on the implications of the heat wave for urban resilience, emphasising the crucial importance of understanding the urban environment as a complex and interconnected system.  相似文献   
634.
Climate change will impact on ecological, social, and economic elements of fisheries; however, the three are seldom considered in an integrated fashion. We develop a fishery-level assessment of economic resilience to climate change for the Tasmanian rock lobster fishery, a linked social–ecological system. We outline the main climate change forcing influences that link climate change to the fishery via changes in lobster abundance, distribution, and phenology. Using a bottom-up approach, we identify twelve economic attributes strongly related to the fisheries’ economic resilience to climate change. Resilience attributes are grouped according to the level of the economic domain (business, sectoral, and governance). Attributes are then evaluated to determine the overall economic resilience of the rock lobster fishery in the context of the specific nature of predicted climate change effects. We identify areas of low resilience in the economic sub-system for this fishery. Evaluating the economic resilience of regional fisheries using this integrated, interdisciplinary framework provides a practical, parsimonious, and conceptually sound basis for undertaking comprehensive and contextually tailored assessments of climate change impacts and economic vulnerability. The framework can be extended to include a broader range of climate change impacts and the social domain of the human sub-system.  相似文献   
635.
Survey results of citizen science water data collection volunteers are presented, indicating personal benefits (e.g., being in nature, helping local water quality), and suggesting potential long-term benefits of improved watershed health (e.g., behavior change). These results can inform citizen science program development and contribute to watershed planners’ understanding of the broad benefits of such programs. We suggest that respondents’ positive feelings toward the watershed's major river and desire to learn about science and nature are place-specific elements that watershed and citizen science program managers could utilize in program development. Moreover, we explore the potential of social diffusion and behavior change and suggest the need for further research in these areas. We conclude that citizen science has potential not just as a means to collect large amounts of data (cheaply), but as a means to engage citizens to make environmentally friendly decisions.  相似文献   
636.
Goals play important roles in people's lives because they focus attention, mobilize effort, and sustain motivation. Understanding conservationists’ satisfaction with goal progress may provide insights into real-world environmental trends and flag risks to their well-being and motivation. We asked 2694 conservationists working globally how satisfied they were with progress toward goals important to them. We then explored how this satisfaction varied among groups, including demographic and occupational. Finally, we looked at respondents' experiences associated with goal-progress satisfaction. Many (94.0%) indicated that making a meaningful contribution to conservation was an important goal for them, and over half were satisfied or very satisfied in this area (52.5%). However, respondents were generally dissatisfied with progress on collective conservation goals (e.g., stopping species loss). Some groups were more likely to report dissatisfaction than others. For instance, those in conservation for longer tended to be less satisfied with collective goal progress (log odds –0.21, 95% credibility interval [CI] –0.32 to –0.10), but practitioners reported greater satisfaction (log odds 0.38, 95% CI 0.15–0.60). Likewise, those who were more optimistic in life (log odds 0.24, 95% CI 0.17–0.32), male (log odds 0.25, 95% CI 0.10–0.41), and working in conservation practice (log odds 0.25, 95% CI 0.08–0.43) reported greater satisfaction with individual goal progress. Free-text responses suggested widespread dissatisfaction with livelihood goals, particularly related to job security and adequate compensation. Although contributing to conservation appeared to be a source of satisfaction, slow goal progress in other areas––particularly around making a living––looked to be a source of distress and demotivation. Employers, funders, professional societies, and others should consider ways to help those in the sector make a difference while making a satisfactory living by, for example, prioritizing conservationists′ well-being when allocating funding. This support could include avoiding exploitative practices, fostering supportive work environments, and celebrating positive outcomes.  相似文献   
637.
We employed qualitative methods to explore how conflict over water collection and use impacts women, and the role that women play in water management and conflict resolution in Marsabit, Kenya. Conflicts between domestic and livestock water led to insufficient water for domestic use and intra-household conflict. Women’s contributions to water management were valued, especially through informal initiatives, though involvement in statutory water management committees was not culturally appropriate. Promoting culturally appropriate ways to involve women in water management, rather than merely increasing the percentage of women on water committee, may reduce conflicts and increase women’s access to domestic water supplies.  相似文献   
638.
Student scientists have analyzed groundwater used for drinking water in rural areas to understand groundwater quality. This was part of a greater effort to understand risks to drinking water. The data produced by middle level and high school students have not been accepted by experts because of concerns about method and student accuracy. We assessed the inherent errors associated with method accuracy, student precision, and sample variability to establish bounds for attainable trueness in water analyses. Analytical test kits and probes were evaluated for the determination of pH, conductivity, chloride, hardness, iron, total soluble metals, and nitrate. In terms of precision, all methods met or exceeded design specifications. Method trueness was variable and in general ranged from good to poor depending on method. A gage reproducibility and repeatability analysis of instrumental methods (pH and conductivity) partitioned the variances into student error (12‐46%), instrumental error (8‐21%), and random error (45‐68%). Overall, student‐generated data met some of the quality objectives consistent with the method limitations. Some methods exhibited a systematic bias and data adjustment may be necessary. Given good management of the student analyst process, it is possible to make precise and accurate measurements consistent with the methods specifications.  相似文献   
639.
We studied the effects of tree species on leaf litter decomposition and forest floor dynamics in a common garden experiment of 14 tree species (Abies alba, Acer platanoides, Acer pseudoplatanus, Betula pendula, Carpinus betulus, Fagus sylvatica, Larix decidua, Picea abies, Pinus nigra, Pinus sylvestris, Pseudotsuga menziesii, Quercus robur, Quercus rubra, and Tilia cordata) in southwestern Poland. We used three simultaneous litter bag experiments to tease apart species effects on decomposition via leaf litter chemistry vs. effects on the decomposition environment. Decomposition rates of litter in its plot of origin were negatively correlated with litter lignin and positively correlated with mean annual soil temperature (MAT(soil)) across species. Likewise, decomposition of a common litter type across all plots was positively associated with MAT(soil), and decomposition of litter from all plots in a common plot was negatively related to litter lignin but positively related to litter Ca. Taken together, these results indicate that tree species influenced microbial decomposition primarily via differences in litter lignin (and secondarily, via differences in litter Ca), with high-lignin (and low-Ca) species decomposing most slowly, and by affecting MAT(soil), with warmer plots exhibiting more rapid decomposition. In addition to litter bag experiments, we examined forest floor dynamics in each plot by mass balance, since earthworms were a known component of these forest stands and their access to litter in litter bags was limited. Forest floor removal rates estimated from mass balance were positively related to leaf litter Ca (and unrelated to decay rates obtained using litter bags). Litter Ca, in turn, was positively related to the abundance of earthworms, particularly Lumbricus terrestris. Thus, while species influence microbially mediated decomposition primarily through differences in litter lignin, differences among species in litter Ca are most important in determining species effects on forest floor leaf litter dynamics among these 14 tree species, apparently because of the influence of litter Ca on earthworm activity. The overall influence of these tree species on leaf litter decomposition via effects on both microbial and faunal processing will only become clear when we can quantify the decay dynamics of litter that is translocated belowground by earthworms.  相似文献   
640.
A major goal of our selenium (Se) phytoremediation research is to use genetic engineering to develop fast-growing plants with an increased ability to tolerate, accumulate, and volatilize Se. To this end we incorporated a gene (encoding selenocysteine methyltransferase, SMT) from the Se hyperaccumulator, Astragalus bisulcatus, into Indian mustard (LeDuc, D.L., Tarun, A.S., Montes-Bayón, M., Meija, J., Malit, M.F., Wu, C.P., AbdelSamie, M., Chiang, C.-Y., Tagmount, A., deSouza, M., Neuhierl, B., B?ck, A., Caruso, J., Terry, N., 2004. Overexpression of selenocysteine methyltransferase in Arabidopsis and Indian mustard increases selenium tolerance and accumulation Plant Physiol. 135, 377-383.). The resulting transgenic plants successfully enhanced Se phytoremediation in that the plants tolerated and accumulated Se from selenite significantly better than wild type. However, the advantage conferred by the SMT enzyme was much less when Se was supplied as selenate. In order to enhance the phytoremediation of selenate, we developed double transgenic plants that overexpressed the gene encoding ATP sulfurylase (APS) in addition to SMT, i.e., APSxSMT. The results showed that there was a substantial improvement in Se accumulation from selenate (4 to 9 times increase) in transgenic plants overexpressing both APS and SMT.  相似文献   
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