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Due to growing environmental challenges, the demand for effective management through pro-environmental policy measures is increasing. The effectiveness is, however, largely determined by the degree to which the policy measures are supported by the actors affected by them. A consistent finding in the literature is that ideology (or subjective positioning on the left–right dimension) affects environmental policy support, with left-leaning individuals being more pro-environmental. A major caveat with previous research is that it seldom makes a distinction between different kinds of policies. Therefore, we are concerned with investigating how different ideological positions affect attitudes towards different forms of environmental protection. Using unique survey data, we show that ideology is related to conceptions about the fairness and effectiveness of different policy tools, which in turn steer preferences. In that sense, this paper makes the discussion on the effects of ideological position on pro-environmental policy support more nuanced. 相似文献
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Moreno Di Marco Thomas Brooks Annabelle Cuttelod Lincoln D.C. Fishpool Carlo Rondinini Robert J. Smith Leon Bennun Stuart H.M. Butchart Simon Ferrier Ruud P.B. Foppen Lucas Joppa Diego Juffe‐Bignoli Andrew T. Knight John F. Lamoreux Penny F. Langhammer Ian May Hugh P. Possingham Piero Visconti James E.M. Watson Stephen Woodley 《Conservation biology》2016,30(2):392-402
World governments have committed to increase the global protected areas coverage by 2020, but the effectiveness of this commitment for protecting biodiversity depends on where new protected areas are located. Threshold‐ and complementarity‐based approaches have been independently used to identify important sites for biodiversity. We brought together these approaches by performing a complementarity‐based analysis of irreplaceability in important bird and biodiversity areas (IBAs), which are sites identified using a threshold‐based approach. We determined whether irreplaceability values are higher inside than outside IBAs and whether any observed difference depends on known characteristics of the IBAs. We focused on 3 regions with comprehensive IBA inventories and bird distribution atlases: Australia, southern Africa, and Europe. Irreplaceability values were significantly higher inside than outside IBAs, although differences were much smaller in Europe than elsewhere. Higher irreplaceability values in IBAs were associated with the presence and number of restricted‐range species; number of criteria under which the site was identified; and mean geographic range size of the species for which the site was identified (trigger species). In addition, IBAs were characterized by higher irreplaceability values when using proportional species representation targets, rather than fixed targets. There were broadly comparable results when measuring irreplaceability for trigger species and when considering all bird species, which indicates a good surrogacy effect of the former. Recently, the International Union for Conservation of Nature has convened a consultation to consolidate global standards for the identification of key biodiversity areas (KBAs), building from existing approaches such as IBAs. Our results informed this consultation, and in particular a proposed irreplaceability criterion that will allow the new KBA standard to draw on the strengths of both threshold‐ and complementarity‐based approaches. 相似文献
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The role of time and species identities in spatial patterns of species richness and conservation 下载免费PDF全文
Many conservation actions are justified on the basis of managing biodiversity. Biodiversity, in terms of species richness, is largely the product of rare species. This is problematic because the intensity of sampling needed to characterize communities and patterns of rarity or to justify the use of surrogates has biased sampling in favor of space over time. However, environmental fluctuations interacting with community dynamics lead to temporal variations in where and when species occur, potentially affecting conservation planning by generating uncertainty about results of species distribution modeling (including range determinations), selection of surrogates for biodiversity, and the proportion of biodiversity composed of rare species. To have confidence in the evidence base for conservation actions, one must consider whether temporal replication is necessary to produce broad inferences. Using approximately 20 years of macrofaunal data from tidal flats in 2 harbors, we explored variation in the identity of rare, common, restricted range, and widespread species over time and space. Over time, rare taxa were more likely to increase in abundance or occurrence than to remain rare or disappear and to exhibit temporal patterns in their occurrence. Space–time congruency in ranges (i.e., spatially widespread taxa were also temporally widespread) was observed only where samples were collected across an environmental gradient. Fifteen percent of the taxa in both harbors changed over time from having spatially restricted ranges to having widespread ranges. Our findings suggest that rare species can provide stability against environmental change, because the majority of species were not random transients, but that selection of biodiversity surrogates requires temporal validation. Rarity needs to be considered both spatially and temporally, as species that occur randomly over time are likely to play a different role in ecosystem functioning than those exhibiting temporal structure (e.g., seasonality). Moreover, temporal structure offers the opportunity to place management and conservation activities within windows of maximum opportunity. 相似文献
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Gebrehaweria Gebregziabher Lisa-Maria Rebelo Simon Langan 《Environment, Development and Sustainability》2016,18(2):449-466
In the Blue Nile Basin of Ethiopian highlands, rainfall distribution is extremely uneven both spatially and temporally. Drought frequently results in crop failure, while high rainfall intensities result in low infiltration and high runoff causing soil erosion and land degradation. These combined factors contribute to low agricultural productivity and high levels of food insecurity. Poor land management practices coupled with lack of effective rainwater management strategies aggravate the situation. Over the past two decades, however, the Government of Ethiopia has attempted to address many of these issues through a large-scale implementation of a number of soil and water conservation measures. Despite the success of interventions, uptake and adoption remains low. The conceptual framework of this study is based on the premise that farmers are more likely to adopt a combination of rainwater management technologies as adaptation mechanism against climate variability and agricultural production constraints. This contrasts the previous work that typically examined a single technology without considering the interdependence between technologies. Data used in this study come from household survey in seven watersheds in the Ethiopian Blue Nile Basin. A multivariate probit model was used to account for the potential correlation and interdependence of various components of rainwater management technologies. Our results suggest that rainwater management technologies are related with each other; hence, any effort to promote the adoption of rainwater management technologies has to consider such interdependence of technologies, or failure to do so may mask the reality that farmers face a set of choices in their adoption decisions. 相似文献
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Transgenerational isotope labelling (TRAIL) using enriched stable isotopes provides a novel means of mass-marking marine fish
larvae and estimating larval dispersal. The technique, therefore, provides a new way of addressing questions about demographic
population connectivity and larval export from no-take marine protected areas. However, successful field applications must
be preceded by larval rearing studies that validate the geochemical marking technique, determine appropriate concentrations
and demonstrate that larvae are not adversely affected. Here, we test whether injection of enriched stable barium isotopes
(135Ba and 137Ba) at two dose rates produces unequivocal marks on the otoliths of the coral reef grouper Epinephelus fuscoguttatus. We also assess potential negative effects on reproductive performance, egg size, condition and larval growth due to injection
of adult female fish. The injection of barium isotopes at both 0.5 and 2.0 mg Ba/kg body weight into the body cavities of
gravid female fish was 100% successful in the geochemical tagging of the otoliths of larvae from the first spawning after
injection. The low-dose rate produced no negative effects on eggs or larvae. However, the higher dose rate of 2 mg Ba/kg produced
small reductions in yolk sac area, oil globule area, standard length and head depth of pre-feeding larvae. Given the success
of the 0.5 mg Ba/kg dose rate, it is clearly possible to produce a reliable mark and keep the concentration below any level
that could affect larval growth or survival. Hence, enriched Ba isotope injections will provide an effective means of mass-marking
grouper larvae. 相似文献
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