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Protected area delineation and conservation action are urgently needed on marine islands, but the potential biodiversity benefits of these activities can be difficult to assess due to lack of species diversity information for lesser known taxa. We used linear mixed effects modeling and simple spatial analyses to investigate whether conservation activities based on the diversity of well‐known insular taxa (birds and mammals) are likely to also capture the diversity of lesser known taxa (reptiles, amphibians, vascular land plants, ants, land snails, butterflies, and tenebrionid beetles). We assembled total, threatened, and endemic diversity data for both well‐known and lesser known taxa and combined these with physical island biogeography characteristics for 1190 islands from 109 archipelagos. Among physical island biogeography factors, island area was the best indicator of diversity of both well‐known and little‐known taxa. Among taxonomic factors, total mammal species richness was the best indicator of total diversity of lesser known taxa, and the combination of threatened mammal and threatened bird diversity was the best indicator of lesser known endemic richness. The results of other intertaxon diversity comparisons were highly variable, however. Based on our results, we suggest that protecting islands above a certain minimum threshold area may be the most efficient use of conservation resources. For example, using our island database, if the threshold were set at 10 km2 and the smallest 10% of islands greater than this threshold were protected, 119 islands would be protected. The islands would range in size from 10 to 29 km2 and would include 268 lesser known species endemic to a single island, along with 11 bird and mammal species endemic to a single island. Our results suggest that for islands of equivalent size, prioritization based on total or threatened bird and mammal diversity may also capture opportunities to protect lesser known species endemic to islands. Beneficios de los Taxa Poco Estudiados para la Conservación de la Diversidad de Aves y Mamíferos en Islas  相似文献   
53.
Ex situ conservation strategies for threatened species often require long‐term commitment and financial investment to achieve management objectives. We present a framework that considers the decision to adopt ex situ management for a target species as the end point of several linked decisions. We used a decision tree to intuitively represent the logical sequence of decision making. The first decision is to identify the specific management actions most likely to achieve the fundamental objectives of the recovery plan, with or without the use of ex‐situ populations. Once this decision has been made, one decides whether to establish an ex situ population, accounting for the probability of success in the initial phase of the recovery plan, for example, the probability of successful breeding in captivity. Approaching these decisions in the reverse order (attempting to establish an ex situ population before its purpose is clearly defined) can lead to a poor allocation of resources, because it may restrict the range of available decisions in the second stage. We applied our decision framework to the recovery program for the threatened spotted tree frog (Litoria spenceri) of southeastern Australia. Across a range of possible management actions, only those including ex situ management were expected to provide >50% probability of the species’ persistence, but these actions cost more than use of in situ alternatives only. The expected benefits of ex situ actions were predicted to be offset by additional uncertainty and stochasticity associated with establishing and maintaining ex situ populations. Naïvely implementing ex situ conservation strategies can lead to inefficient management. Our framework may help managers explicitly evaluate objectives, management options, and the probability of success prior to establishing a captive colony of any given species.  相似文献   
54.
We compared the results from fixed acoustic transmitters and transmitters implanted in lingcod Ophiodon elongatus provided by two fine-scale passive acoustic monitoring systems: the older Vemco? Radio Acoustic Positioning (VRAP) system and the newer VR2W Positioning System (VPS) with either three or four receivers. The four-receiver VPS method calculated five times more positions of lingcod than VRAP and more than twice as many as the three-receiver VPS. Calculated positions of fixed transmitters were less precise with VRAP than either VPS approach. Measurements of home range for lingcod were similar between the four-receiver VPS and VRAP, which were both greater than the three-receiver VPS. Comparisons varied when lingcod were in/near complex habitats. As new technology develops, it is important to understand how new methods compare to previous methods. This may be important when describing patterns of movement or habitat use in the context of changes in habitat or management efforts.  相似文献   
55.
This paper presents a case-study of valuation of public access to a woodland site owned by The Crown Estate in Windsor Forest. It supports the view that contingent valuation is an appropriate technique to use for assessing recreational benefits in the countryside and that consistent and useful results can be obtained. The study found that the recreational benefits far outweighed the costs of access provision, thus giving reassurance to the providers that their efforts are worthwhile.  相似文献   
56.
The movement of copper, chromium and arsenic originating from samples of the wood preservative Tanalith® through mildly acidic, sandy loam soil was investigated. Small, undisturbed soil cores (of dimensions 15 × 15 × 15 cm) were removed from the topsoil of a paddock adjacent to the Glenelg River in the Western District of Victoria, Australia. The paddock soils were thin (<30cm) greyish brown, mildly acidic, sandy loams with a moderate organic carbon content (2–5%) overlying a limestone cap. Tanalith® was applied to the surface of the cores which were then irrigated with deionised water at approximately 30 mm day‐1. Copper concentrations in all leachate remained at background levels throughout the experiment, and this element was found to be immobilised in the top 4 cm of the soil. Up to 29% of the applied dose of chromium was detected in the leachate, with breakthrough occurring within 20 days of Tanalith® application. Up to 13% ofthe applied dose ofarsenic was detected in the leachate, although in this case breakthrough was not observed until 25 days after Tanalith® application and leachate concentrations were still rising when the experiment came to a close. Significant concentrations of arsenic and chromium were found in the top 6 cm of the soil profile.  相似文献   
57.
Environmentally sustainable development is one of the key challenges faced by societies today. Yet it is not a new challenge; throughout history, societies have faced the need to live within environmental constraints. Some have done so well, and some poorly. One society which did well for tens of thousands of years is that of Aboriginal Australia. This paper explores some lessons from Aboriginal Australia which have resonance in the modern world and shows that countries which have learned those lessons are in fact more sustainable than those which have not. It thus suggests that there is much that the pantheon of human experience can teach the modern world as it endeavours to create a sustainable future.  相似文献   
58.
Mercury has various uses in nuclear fuel reprocessing and other nuclear processes, and so it is often present in radioactive and mixed (radioactive and hazardous) wastes. Compliance with air emission regulations such as the Hazardous Waste Combustor (HWC) Maximum Achievable Control Technology (MACT) standards can require off-gas mercury removal efficiencies up to 99.999% for thermally treating some mixed waste streams. Test programs have demonstrated this level of off-gas mercury control using fixed beds of granular sulfur-impregnated activated carbon. Other results of these tests include (1) the depth of the mercury control mass transfer zone was less than 15-30 cm for the operating conditions of these tests; (2) MERSORB carbon can sorb mercury up to 19 wt % of the carbon mass; and (3) the spent carbon retained almost all (98.3-99.99%) of the mercury during Toxicity Characteristic Leachability Procedure (TCLP) tests, but when even a small fraction of the total mercury dissolves, the spent carbon can fail the TCLP test when the spent carbon contains high mercury concentrations.  相似文献   
59.
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‘Environmental cognitive stress’ a hybrid model combining environmental stress and cognitive determinants of pro-environmental behavior is explored among Australians living in contrasting ‘micro’ climates in the same river catchment system. Peoples’ climate risk perceptions are mediated by their connections to local environment, observations of environmental change and personal weather experiences. A longitudinal study randomly sampled 1,162 Hunter Valley coastal and rural residents in New South Wales. Telephone interviewers (2008) recruited lakeside homeowners ‘at risk’ of sea level rise, nearby ‘control’ residents and a comparable farming area group. Follow-up interviews (2011) located 81.5 % of the original sample. Fifty-six items based on the model asked about climate change observations, concerns, impacts and actions. Statistically significant rural–suburban and time differences were found. The rural sample was attuned to conditions affecting agricultural productivity: They worried about drought and heat, saw trees dying and changes to seasons and natural rhythms. They anticipate the impact of water scarcity, conserve water and value protecting plants and animals. Compared to higher elevation residents, lake dwellers observed marine life loss, worry about sea level rise and predict the decline of property values. Across time, all groups’ perceptions of warming indicators declined. Concerns and impacts were high and generally stayed high, as did actions related to energy use. No differences emerged in beliefs about climate warming. Climate change observations, along with concerns and actions, have important implications for the environmental cognitive stress model. Overall, dynamic changes in residents’ understandings are related to a changing policy environment, the vicissitudes of climate debates and weather experiences, including extreme swings from inundation to drought.  相似文献   
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