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11.
Large‐scale change in human values and associated behavior change is believed by some to be the ultimate solution to achieve global biodiversity conservation. Yet little is known about the dynamics of values. We contribute to this area of inquiry by examining the trajectory of values affecting views of wildlife in North America. Using data from a 19‐state study in the United States and global data from the Schwartz Value Survey, we explored questions of value persistence and change and the nature of attitudinal responses regarding wildlife conservation issues. We found support, based on subjects’ ancestry, for the supposition that domination is a prevalent American value orientation toward wildlife that has origins in European Judeo‐Christian traditions. Independent of that effect, we also found indications of change. Modernization is contributing to a shift from domination to mutualism value orientations, which is fostering attitudes less centered on human interests and seemingly more consistent with a biocentric philosophy. Our findings suggest that if value shift could be achieved in a purposeful way, then significant and widespread behavior change believed necessary for long‐term conservation success may indeed be possible. In particular, greater emphasis on mutualism values may help provide the context for more collaborative approaches to support future conservation efforts. However, given the societal forces at play, it is not at all clear that human‐engineered value shift is tenable. Instead of developing strategies aimed at altering values, it may be more productive to create strategies that recognize and work within the boundaries of existing values. Whereas values appear to be in a period of flux, it will be difficult to predict future trends without a better understanding of value formation and shift, particularly under conditions of rapid social‐ecological change.  相似文献   
12.
Abstract: The links between species–environment relations and species’ responses to protection are unclear, but the objectives of marine protected areas (MPAs) are most likely to be achieved when those relations are known and inform MPA design. The components of a species’ habitat vary with the spatial resolution of the area considered. We characterized areas at two resolutions: 250 m2 (transect) and approximately 30,000 m2 (seascape). We considered three categories of environmental variables: substrate type, bottom complexity, and depth. We sought to determine at which resolution habitat characteristics were a better predictor of abundance and species composition of fishes and whether the relations with environmental variables at either resolution affected species’ responses to protection. Habitat features accounted for a larger proportion of spatial variation in species composition and abundances than differences in protection status. This spatial variation was explained best by habitat characteristics at the seascape level than at the transect level. Species’ responses to protected areas were specific to particular seascape characteristics, primarily depth, and bottom complexity. Our method may be useful for prioritizing marine areas for protection, designing MPAs, and monitoring their effectiveness. It identified areas that provided natural shelter, areas acting as buffer zones, and areas where fish species were most responsive to protection. The identification of such areas is necessary for cost‐effective establishment and monitoring of MPAs.  相似文献   
13.
14.
Coral reef fisheries support the livelihoods of millions of people but have been severely and negatively affected by anthropogenic activities. We conducted a systematic review of published data on the biomass of coral reef fishes to explore how the condition of reef fisheries is related to the density of local human populations, proximity of the reef to markets, and key environmental variables (including broad geomorphologic reef type, reef area, and net productivity). When only population density and environmental covariates were considered, high variability in fisheries conditions at low human population densities resulted in relatively weak explanatory models. The presence or absence of human settlements, habitat type, and distance to fish markets provided a much stronger explanatory model for the condition of reef fisheries. Fish biomass remained relatively low within 14 km of markets, then biomass increased exponentially as distance from reefs to markets increased. Our results suggest the need for an increased science and policy focus on markets as both a key driver of the condition of reef fisheries and a potential source of solutions. Efectos Globales de la Densidad de Población Humana Local y la Distancia a los Mercados sobre la Condición de Pesquerías en Arrecifes de Coral  相似文献   
15.
The level of water was manipulated in a freshwater wetland, with the aim of enhancing abundances of benthic animals and, ultimately, improving habitat for feeding birds (Japanese Snipe, Gallinago hardwickii). We tested whether these actions had the predicted and desired effects on benthic animals, by contrasting changes in two managed locations to one control location which was left unmanipulated. The number of taxa and abundances of chironomids decreased strongly and significantly in the manipulated locations, while the abundance of oligochaetes appeared to vary in a seasonal manner. Temporal variability of the structure and composition of assemblages was also increased in manipulated locations. Such effects have previously been suggested to indicate stress in benthic assemblages. Therefore, in contrast to what was predicted, managerial actions made benthic fauna less abundant and thus, less suitable as habitat for feeding birds. Several general lessons can be learned from these results. (1) Effects of managerial actions like these are difficult to predict a priori and can only be reliably evaluated with an experimental framework. (2) Because abundances of animals vary naturally, evaluations of managerial actions must include appropriate spatial replication. (3) Sampling at hierarchical temporal scales is important, because abundances of animals may vary in an unpredictable manner at short temporal scales and because changes in temporal variability may be a symptom of stress. (4) Combined use of uni- and multivariate techniques provides a comprehensive set of tools to assess the effects of restoration and creation of new habitats. Finally, these results emphasise the need for clear predictions about desired outcomes and specific experimental plans about how to test whether the desired results were achieved, before managerial actions are taken. Although this is often very difficult to achieve in real situations, it is necessary for practices of management to evolve on the basis of sound empirical experience.  相似文献   
16.
Within the rotational scheme developed by the Programme to fight the resistance of Simulium damnosum to chemical larvicides, there was an operational gap at discharges between 5 and 70 m3 s−1 for the treatment of rivers where resistance to organophosphates was present. The use of permethrin and carbosulfan was precluded because of risk of environmental impact and, Bacillus thuringiensis ser. H-14 treatments were not envisageable due to cost and logistics constraints. Among the possible complementary groups of larvicides tested, the pseudo-pyrethroids, held promise, because of a mode of action similar to that of pyrethroids, but along with a usually lower toxicity for fish. Etofenprox, one of the pseudo-pyrethroids tested, shows a global detachment of non-target insects in 24 h close to that of pyraclofos, an organo-phosphorus compound (27 against 23%). In laboratory conditions, six times the operational dose which is 0.03 mg l−1 10 min, is needed to cause 50% mortality of Caridina sp. (a small shrimps species) and 30 times this same dose for 95% mortality. For fish species, a safety margin of 400–800 times the operational dose is observed for Oreochromis niloticus and 200–400 times for Tilapia zillii.  相似文献   
17.
Abstract:  The World Conservation Union (IUCN) Red List Index (RLI) is used to measure global trends in the status of biodiversity. We examined how the index might be used to measure the trend in the status of indigenous breeding birds in British Columbia between 1992 and 2006. We followed the RLI method described by Butchart et al. (2004, 2007) as closely as possible . Because IUCN Red List assessments at the regional level are not available in British Columbia, we used NatureServe S (subnational) ranking data. We calculated three index trend lines. The first two of these allowed us to compare an index based on our original data to one based on data that had been retrospectively corrected; the latter produced a smooth, flat line. A third trend line, based on the corrected data but excluding species new to province since 1947, produced a gently sloping downward trend. Ongoing immigration of bird species in and out of British Columbia added to the complexity of interpreting our regional RLI-type index, especially because our S-rank data did not incorporate transboundary "rescue" effects. Because the RLI is scaled so that the maximum value is based on a state in which all species are simultaneously ranked as least concern, it may exaggerate the highest potential status of intrinsically vulnerable species. A simpler, more intuitive graphic allows reporting that is less dependent on context. We believe the RLI approach holds useful innovation for an indicator of change in biodiversity within jurisdictional boundaries.  相似文献   
18.
The population density and relative abundance of some bird species reach the highest values in the communities of habitats with a high degree of anthropogenic transformation. The species diversity of birds shows an inverse correlation with the index of anthropogenic impact (in grades) calculated with regard to a number of parameters. Relevant correlations change periodically, with the correlation coefficient reaching the highest values in the nesting period and decreasing to a minimum during the flight period.  相似文献   
19.
To reveal the effect of forest fires on the avifauna of the Northern Amur Region, bird assemblages of primary dark conifer-deciduous forests, wild rosemary larch forests, and secondary larch-birch forests have been studied in the Komsomol’skii and Norskii nature reserves. It has been shown that the replacement of primary dark conifer-deciduous forests by secondary forests is accompanied by a significant decrease in bird population density, with some species being lost and the composition of the dominant species group being changed. On the other hand, fires lead to increasing patchiness of the environment, which can sometimes provide for an increase in biological diversity.  相似文献   
20.
Species richness, taxonomic diversity, and qualitative composition of the butterfly fauna (Lepidoptera, Diurna) are discussed in the light of data on the altitudinal zonality of local faunas in the southern Far East and Transbaikalia. It is shown that qualitative elevation-dependent changes in the fauna occur only in the western and northern parts of the region.  相似文献   
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