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41.
In this paper we explore the challenges involved in engaging the full range of stakeholders needed for effective marine resource management in the transboundary Grenadine Islands shared by the small island developing States (SIDS) of Saint Vincent and the Grenadines and Grenada. The study describes the ways stakeholders were engaged in the development of participatory geographic information systems (PGIS), both in terms of the research approach (process) and the final geodatabase (product); it illustrates how the approach provides a practical means to strengthen aspects of marine governance, particularly in a SIDS context. We found that PGIS can provide a foundation for ecosystem‐based transboundary marine governance. The advantages of this approach are two‐fold: it provides the fullest possible range of information as input for the management of marine resources and it engages the stakeholders. This engagement takes several forms: capacity to participate in research; ownership of information produced; increased stakeholder understanding; empowerment through access to information; capacity to interact with other stakeholders for information and problem‐solving; and competence to participate in actual governance processes. Lastly, we discuss considerations for other practitioners contemplating using PGIS, particularly those working in similar resource‐limited SIDS environments.  相似文献   
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Academics and policy-makers claim that community-based organisations may be able to encourage individuals to adopt pro-environmental behavioural changes; however, at present, there is limited research-based evidence to support this assertion. This paper sets out to provide a contribution to the evidence base by examining the role that community can play in tackling climate change. It does this through a case study analysis of a community-based pro-environmental behavioural-change campaign – Ipswich Town Football Club's “Save Your Energy for the Blues” campaign. The paper examines existing theories on encouraging behavioural change based on a range of cognitive and contextual constraints. Based on the findings of this research, the paper goes on to suggest that by focusing on the individual as the appropriate unit of change, much current policy fails to incorporate the contextual constraints that may limit an individual's ability to adopt behavioural change regardless of their willingness to do so. The case study analysis indicates how framing of appropriate responses to climate change in a largely positive light, with a range of individual, collective and environmental benefits, is shown to have resonated strongly with many participants in the campaign, including a significant number whose participation was not based on pro-environmental values.  相似文献   
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Population viability analysis programs are being used increasingly in research and management applications, but there has not been a systematic study of the congruence of different program predictions based on a single data set. We performed such an analysis using four population viability analysis computer programs: GAPPS, INMAT, RAMAS/AGE, and VORTEX. The standardized demographic rates used in all programs were generalized from hypothetical increasing and decreasing grizzly bear ( Ursus arctos horribilis ) populations. Idiosyncracies of input format for each program led to minor differences in intrinsic growth rates that translated into striking differences in estimates of extinction rates and expected population size. In contrast, the addition of demographic stochasticity, environmental stochasticity, and inbreeding costs caused only a small divergence in viability predictions. But, the addition of density dependence caused large deviations between the programs despite our best attempts to use the same density-dependent functions. Population viability programs differ in how density dependence is incorporated, and the necessary functions are difficult to parameterize accurately. Thus, we recommend that unless data clearly suggest a particular density-dependent model, predictions based on population viability analysis should include at least one scenario without density dependence. Further, we describe output metrics that may differ between programs; development of future software could benefit from standardized input and output formats across different programs.  相似文献   
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The potential effects of sucralose on the Arctic copepods Calanus finmarchicus and Calanus glacialis were studied in Disko Bay, Greenland. Sucralose is a non-calorie sweetener and chlorine derivate of sucrose containing three chlorine atoms. Scandinavian screening studies of sucralose in 2007, revealed sucralose in all effluent samples. To investigate whether sucralose is harmful to the Arctic aquatic ecosystems, possible short-term effects were investigated on egg production, hatching rate, food intake and mortality of two species of Arctic copepods. The copepods were exposed to six different concentrations (0–50,000 ng · L?1) of sucralose, which spans the range of concentrations found in the screening studies. Exposure led to no mortality among the copepods. Food intake by C. glacialis increased with increasing concentrations of sucralose. In C. finmarchicus, food intake did not differ with increasing concentrations. No effect of sucralose was observed on egg production of C. finmarchicus. Despite increased food intake with increasing concentrations of sucralose, C. glacialis did not increase its egg production. The results show that both species responded weakly to sucralose, but with C. glacialis being possibly slightly more sensitive to sucralose than C. finmarchicus.  相似文献   
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Conservation planners are faced with numerous choices regarding ‘what to connect’ when modeling landscape networks on an ecoregion scale. A simplifying assumption is often that coarse-scale corridors may provide overlapping or ‘umbrella’ effects for multiple conservation scenarios. To examine this, we assessed differences in connectivity models arising from four different conservation scenarios for the transboundary Northern Appalachian/Acadian Ecoregion (330,000 km2). Models resulted in networks comprised of varying levels of connectedness, suggesting the presence of local connectivity at several sub-ecoregion scales, but diminished ecoregion-scale connectivity. Our results also indicate that selecting ‘what to connect’ at the ecoregion scale strongly influences the location and extent of modeled corridors. Further, our evidence suggests that landscape networks derived for one scenario are not likely to produce far-reaching corridor umbrellas or highly coincident landscape networks for alternative conservation scenarios with varying goals. As a result, alternative landscape networks should not be considered functionally equivalent.  相似文献   
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ABSTRACT: A regression analysis using a generalized least squares approach on flow data from the driftless area of Wisconsin indicates that the ratio of drainage area to time-to-peak is a good predictor of flood quantiles. The estimation of time-to-peak (or some other measure of basin response time) requires direct measurement of river stage and possibly rainfall at the site of which the quantiles are to be estimated. The cost-effectiveness of such an approach must yet be determined.  相似文献   
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Gallic acid, tannic acid mixture and a purified fraction of tannic acid were evaluated for possible mutagenic activity in three strains of Salmonella typhimurium, TA98, TA100, and TA1535. These chemicals were not mutagenic either before or after activation with rat and woodchuck microsomal and cytosolic enzymes. However, tannic acid mixture and tannic acid fraction both gave a significantly (p = 0.05) dose-related reduction in the number of the revertant colonies, compared to the normal spontaneous revertants with no apparent toxic effects in the background lawn. With an agar diffusion assay, the chemicals exhibited toxic effects at 5000 micrograms/disc.  相似文献   
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