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81.
This paper describes efforts to bridge the gap between the existing research and proposed recreation access management for public lands in southwestern Alberta, Canada. Recreation access management has been identified as a complex problem and public consultation is one element in addressing the complexity. An Internet-based survey (n = 945) examined the acceptability and desirability of public consultation processes to assist with access management planning. Non-parametric tests indicate significant differences in desirability of public consultation types existed for all variables except gender. Respondents expressed the desire for a diversity of public consultation approaches with a strong preference for face-to-face field visits. Mechanisms for engagement in access management planning should be based on public consultation preferences to ensure broad, on going engagement and subsequent user acceptance and compliance.  相似文献   
82.
ABSTRACT: A one-dimensional hydraulic transient model has been designed for water resource studies of Lake Ontario and the Upper St. Lawrence River. The model simulates water surface profiles and flows in the St. Lawrence River between Lake Ontario and the Moses-Saunders Power Dam under both open water and ice-covered conditions. Errors in water surface elevations were found to be less than 0.2 feet during quasi-steady conditions on the river. Comparable errors occurred during the ice-covered conditions. A sensitivity analysis found the model to be most sensitive to the roughness coefficients and the flow through the power dam.  相似文献   
83.
Consistent individual differences in behavior, commonly termed animal personality, are a widespread phenomenon across taxa that have important consequences for fitness, natural selection, and trophic interactions. Animal personality research may prove useful in several conservation contexts, but which contexts remains to be determined. We conducted a structured literature review of 654 studies identified by combining search terms for animal personality and various conservation subfields. We scored the relevance of personality and conservation issues for each study to identify which studies meaningfully integrated the 2 fields as opposed to surface-level connections or vague allusions. We found a taxonomic bias toward mammals (29% of all studies). Very few amphibian or reptile studies applied personality research to conservation issues (6% each). Climate change (21%), invasive species (15%), and captive breeding and reintroduction (13%) were the most abundant conservation subfields that occurred in our search, though a substantial proportion of these papers weakly integrated conservation and animal personality (climate change 54%, invasive species 51%, captive breeding and reintroduction 40%). Based on our results, we recommend that researchers strive for consistent and broadly applicable terminology when describing consistent behavioral differences to minimize confusion and improve the searchability of research. We identify several gaps in the literature that appear to be promising and fruitful avenues for future research, such as disease transmission as a function of sociability or exploration as a driver of space use in protected areas. Practitioners can begin informing future conservation efforts with knowledge gained from animal personality research.  相似文献   
84.
All other things being equal, the lifetime reproductive success (LRS) of iteroparous and semelparous individuals should scale with the number of breeding seasons. Deviations from this relationship may occur for many reasons, including age- or size-related fecundity or life history trade-offs, which may differ between sexes. We used 19 brood years of DNA parentage analysis in a small (N = 4–143 year−1) wild, unexploited population of steelhead trout (Oncorhynchus mykiss) to compare the LRS of individuals that spawned only once [“one time spawners” (OTS), N = 355 male, 371 female] to those spawning twice [“repeat spawners” (RPS), N = 13 male, 49 female]. Female RPS had nearly twice the LRS of female OTS (1.17 offspring per female vs 0.91 offspring per female), whereas male RPS had nearly three times the LRS of male OTS (1.54 offspring per male vs 0.57 offspring per male). Female RPS produced slightly more adult offspring during their second breeding season than their first (0.78 vs 0.82 offspring per female); however, male RPS produced all of their adult offspring in their second breeding season (0 vs 1.54 offspring per male). The additional growth in body size of males between breeding seasons may give them an advantage in their second breeding season, but the lack of offspring produced in their first season suggests a trade-off between survival and future reproduction that was not expressed in females.  相似文献   
85.
Adaptive sampling and analysis programs (ASAPs) provide a cost-effective alternative to traditional sampling program designs. ASAPs are based on field analytical methods for rapid sample turnaround and field-based decision support for guiding the progress of the sampling program. One common objective of ASAPs is to delineate contamination present in soils, either to support feasibility studies or remedial action designs. An ASAP based on portable gas chromatograph/ mass spectrograph (GC/MS) technologies developed at Tufts University combined with decision support tools created at Argonne National Laboratory was used to delineate explosives contamination in soils at Joliet Army Ammunition Plant, Joliet, Illinois. Tufts' GC/MS technologies provided contaminant-specific identification and quantification with rapid sample turnaround and high sample throughput. Argonne's decision support tools estimated contamination extent, determined the uncertainty associated with those estimates, and indicated where sampling should continue to minimize uncertainty. In the case of Joliet, per sample analytical costs were reduced by 75 percent as compared to the cost of off-site laboratory analyses for explosives. The use of an ASAP resulted in a much more accurate identification and delineation of contaminated areas than a traditional sampling program would have with the same number of samples collected on a regular grid. While targeting explosives contamination in soils at Joliet, the ASAP technologies used in this demonstration have much broader application.  相似文献   
86.
This paper examines the relationships between community development, sustainable development and economics. In particular the convergence of thought in the realms of strong sustainability and ecological economics are shown to be consistent with the goals of sustainable community development (SCD). It is argued that in order to truly and effectively practice SCD, an economics of sustainability, best represented by ecological economics, should be incorporated into all facets of SCD work. It is suggested that the application of neoclassical or environmental economics is likely to limit the effectiveness of SCD work. Five practical implications of the necessary relationship between SCD and ecological economics are presented, suggesting that SCD practitioners must: (1) seek interdisciplinarity, (2) understand and endorse limits to growth, (3) adopt and endorse alternative measures of success, (4) seek the economic valuation of natural and social capital and (5) ensure the inclusion of equity in discussions of sustainability. Finally, a practical example of those implications is offered by way of a community economic workbook application.  相似文献   
87.
Some birds exploit the aggressiveness of others that are more capable of defending their nests against predators. Usually this behaviour is selected for through improved breeding success for the timid (associate) species. The risk of predation from the more aggressive (host) species is generally rare but may select against the behaviour. The breeding success of red-breasted geese (Branta ruficollis) nesting in association with peregrine falcons (Falco peregrinus) in arctic Siberia was investigated from 1995 to 1999. Nest-predation risk for geese within colonies was positively correlated with distance from the falcons' eyries and negatively correlated with colony size. Though predation risk from the hosts was low, the risk of being attacked by the falcons was high, which we suggest explains why the likelihood of geese deserting their nests was negatively correlated with distance from the eyries. The optimal distance geese nested from eyries was 46 m, though only 37% of pairs managed to nest within 20 m of this. In years with low predation pressure, some geese within colonies nested farther from the falcons. This may be the first evidence to suggest a trade-off between costs and benefits in a nesting association, both of which are directly mediated by the host's nest defence behaviour.  相似文献   
88.
Practical problems facing adaptive cluster sampling with order statistics (acsord) are explored using Monte Carlo simulation for three simulated fish populations and two known waterfowl populations. First, properties of an unbiased Hansen-Hurwitz (HH) estimator and a biased alternative Horvitz-Thompson (HT) estimator are evaluated. An increase in the level of population aggregation or the initial sample size increases the efficiencies of the two acsord estimators. For less aggregated fish populations, the efficiencies decrease as the order statistic parameter r (the number of units about which adaptive sampling is carried out) increases; for the highly aggregated fish and waterfowl populations, they increase with r. Acsord is almost always more efficient than simple random sampling for the highly aggregated populations. Positive bias is observed for the HT estimator, with the maximum bias usually occurring at small values of r. Secondly, a stopping rule at the Sth iteration of adaptive sampling beyond the initial sampling unit was applied to the acsord design to limit the otherwise open-ended sampling effort. The stopping rule induces relatively high positive bias to the HH estimator if the level of the population aggregation is high, the stopping level S is small, and r is large. The bias of HT is not very sensitive to the stopping rule and its bias is often reduced by the stopping rule at smaller values of r. For more aggregated populations, the stopping rule often reduces the efficiencies of the estimators compared to the non-stopping-rule scheme, but acsord still remains more efficient than simple random sampling. Despite its bias and lack of theoretical grounding, the HT estimator is usually more efficient than the HH estimator. In the stopping rule case, the HT estimator is preferable, because its bias is less sensitive to the stopping level.  相似文献   
89.
We tested whether the population structures of intertidal molluscs varied with the activity of human collectors in northern Port Phillip Bay, Victora, Australia. We examined eight sites, two of which had been protected for around 70 years by the area being used as a rifle range with the other six being visited frequently by human. The shores were examined in two different years, and in 1991 we counted humans and recorded their activities. At heavily visited shores, almost half of the people seen were simply walking, while 25% were actively collecting, despite regulations prohibiting the collection of intertidal gastritis. The remaining people were fishing or skydiving. At the protected shores, we observed only one collector and a handful of walkers over more than 20 observation periods, including weekdays, normal weekends, and holiday weekends. In 1989 and 1991, we compared size distributions of seven intertidal species between sites in the two categories. Four mollify species are taken for food and bait; the remaining three served as “controls”. The size distributions and abundance of noncarbonated species (alicized napalm, Leaderless viola, and emization ebonies) did not differ between visited and protected sites in either year, although most species did vary between individual sites. In contrast, three of the four collected species, alicize trampoliners, Austrocochlea constricta, and Nerita atramentosa, were significantly larger at the protected sites, and N. atramentosa was markedly less abundant at heavily visited sites. The fourth collected species, Turbo undulatus, has a distribution extending into the subtidal zone, and it is possible that intertidal populations ate replenished from deeper water. The changes in mean size of molluscs are well within the range reported from South America and South Africa under subsistence fishing, and they demonstrate that at least close to major urban centers, human recreational activities can have substantial effects in developed countries.  相似文献   
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