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41.
Protecting Tourists from Death and Injury in Coastal Storms 总被引:3,自引:0,他引:3
Hurricanes, typhoons, tsunamis and other storms force thousands to flee coastal regions every year. In many cases, resort areas have been severely damaged and tourists placed in jeopardy. This article examines ways tourist businesses can and already have protected holiday-makers from coastal storm hazards through emergency evacuation and other measures. Using data from a sample of large and small hotels in New Orleans, Louisiana, we find considerable variation in protective behaviour. To explain this variation, we look at how perceptions and preparedness differ by both managerial and organisational characteristics. We then suggest a variety of measures that can be taken by hotels in coastal resort areas to reduce risk. 相似文献
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THOMAS DIRNBÖCK§ JOSEF GREIMLER† PATRICIO LOPEZ S.‡ TOD F. STUESSY† 《Conservation biology》2003,17(6):1650-1659
Abstract: The Juan Fernandez Archipelago, a Chilean national park and biosphere reserve, is 700 km west of continental Chile. Invasive plant species pose major threats to the native, highly endemic vegetation, especially on Robinson Crusoe Island (Mas a Tierra), where there is a permanent settlement. We used historical and recent vegetation map data as well as recent vegetational point data to reconstruct vegetational changes on the island since the early twentieth century. In addition, we used logistic regression models with environmental variables or their surrogates (elevation, solar radiation, topographic similarity index, slope position) to estimate the potential distributions of the worst invaders. Native vegetation has been affected most severely by Acaena argentea , Aristotelia chilensis , Rubus ulmifolius , and Ugni molinae , leading to a significant decrease of endemic plants in the montane forests and native shrublands. The native forest has decreased by approximately one-third. The area affected by Aristotelia chilensis increased from 6.5% to 14% of the total island area. Ugni molinae , once rare, is now abundant (4.6%), as is Acaena (11.9%). Rubus ulmifolius , not present 80 years ago, now covers about 7% of the island's surface. The distributions of all studied species except Rubus ulmifolius are significantly ( p < 0.05) controlled by the environmental factors we examined. Inferring from potential distributions of Aristotelia chilensis and Ugni molinae , 50% of the native montane forest could be invaded or replaced (with a probability of >60%) by these plants. Based on the invasion speed of the past 80 years, this would take another 80 years if conservation measures do not succeed. 相似文献
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Species, Data, and Conservation Planning 总被引:7,自引:0,他引:7
THOMAS BROOKS GUSTAVO A. B. da FONSECA †‡ ANA S. L. RODRIGUES 《Conservation biology》2004,18(6):1682-1688
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The Northwest Forest Plan: Origins, Components, Implementation Experience, and Suggestions for Change 总被引:5,自引:0,他引:5
JACK WARD THOMAS JERRY F. FRANKLIN† JOHN GORDON‡ K. NORMAN JOHNSON§ 《Conservation biology》2006,20(2):277-287
Abstract: In the 1990s the federal forests in the Pacific Northwest underwent the largest shift in management focus since their creation, from providing a sustained yield of timber to conserving biodiversity, with an emphasis on endangered species. Triggered by a legal challenge to the federal protection strategy for the Northern Spotted Owl ( Strix occidentalis caurina ), this shift was facilitated by a sequence of science assessments that culminated in the development of the Northwest Forest Plan. The plan, adopted in 1994, called for an extensive system of late-successional and riparian reserves along with some timber harvest on the intervening lands under a set of controls and safeguards. It has proven more successful in stopping actions harmful to conservation of old-growth forests and aquatic systems than in achieving restoration goals and economic and social goals. We make three suggestions that will allow the plan to achieve its goals: (1) recognize that the Northwest Forest Plan has evolved into an integrative conservation strategy, (2) conserve old-growth trees and forests wherever they occur, and (3) manage federal forests as dynamic ecosystems. 相似文献
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Mortality Gradients within and among Dominant Plant Populations as Barometers of Ecosystem Change During Extreme Drought 总被引:7,自引:0,他引:7
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Nonrandom, Size- and Timing-Biased Breeding in a Hatchery Population of Steelhead Trout 总被引:4,自引:0,他引:4
Abstract: Hatcheries have been built and operated to buffer salmon and trout populations from overfishing and to compensate for habitat lost or degraded by human activities. These facilities are now so prevalent that in some cases hatchery-produced salmon outnumber salmon produced in the wild. By default, this makes them an important component in the current ecology and evolution of salmonids. Hatcheries differ from natural environments in many ways, and among the most fundamental is the necessity that humans select fish for breeding instead of allowing natural processes of mate choice and competition. We examined the mating system for steelhead trout ( Oncorhynchus mykiss ) at Forks Creek Hatchery in southwest Washington and investigated factors affecting selection of individual steelhead for spawning by the hatchery staff. Despite efforts by the staff to not spawn selectively, data on steelhead spawned over 7 years revealed selection for large adult body size and early reproductive timing and a tendency for size-assortative mating (i.e., large with large). Selection on size was related to selection on reproductive timing because early returning fish tended to be larger than those returning later. To improve the fitness of both hatchery fish destined to spawn in the wild and hatchery fish designated to be spawned in the hatchery, a better understanding of factors associated with the range of reproductive success and mate-choice mechanisms in the wild is vital. This knowledge may then be applied to artificial propagation programs designed for conservation or enhancement. 相似文献
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RUDOLF S. DE GROOT JAMES BLIGNAUT SANDER VAN DER PLOEG JAMES ARONSON THOMAS ELMQVIST JOSHUA FARLEY 《Conservation biology》2013,27(6):1286-1293
Measures aimed at conservation or restoration of ecosystems are often seen as net‐cost projects by governments and businesses because they are based on incomplete and often faulty cost‐benefit analyses. After screening over 200 studies, we examined the costs (94 studies) and benefits (225 studies) of ecosystem restoration projects that had sufficient reliable data in 9 different biomes ranging from coral reefs to tropical forests. Costs included capital investment and maintenance of the restoration project, and benefits were based on the monetary value of the total bundle of ecosystem services provided by the restored ecosystem. Assuming restoration is always imperfect and benefits attain only 75% of the maximum value of the reference systems over 20 years, we calculated the net present value at the social discount rates of 2% and 8%. We also conducted 2 threshold cum sensitivity analyses. Benefit‐cost ratios ranged from about 0.05:1 (coral reefs and coastal systems, worst‐case scenario) to as much as 35:1 (grasslands, best‐case scenario). Our results provide only partial estimates of benefits at one point in time and reflect the lower limit of the welfare benefits of ecosystem restoration because both scarcity of and demand for ecosystem services is increasing and new benefits of natural ecosystems and biological diversity are being discovered. Nonetheless, when accounting for even the incomplete range of known benefits through the use of static estimates that fail to capture rising values, the majority of the restoration projects we analyzed provided net benefits and should be considered not only as profitable but also as high‐yielding investments. Beneficios de Invertir en la Restauración de Ecosistemas 相似文献