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191.
Assessing the Effectiveness of Reserve Acquisition Programs in Protecting Rare and Threatened Species 总被引:1,自引:0,他引:1
Abstract: Measuring the effectiveness of reserve networks is essential to ensure that conservation objectives such as species persistence are being met. We devised a new approach for measuring the effectiveness of land conservation in protecting rare and threatened species and applied it to an ecosystem of global significance. We compiled detailed global distributional data for 36 rare and threatened plants and animals found in the Lake Wales Ridge ecosystem in central Florida (U.S.A.). For each species, we developed a set of protection indices based in part on criteria used to categorize species for the World Conservation Union's Red List. We calculated protection indexes under three different conservation scenarios: a past scenario, which assumed recent, major land-acquisition efforts never occurred; a current scenario, which assumed no additional areas are saved beyond what is currently protected; and a targeted scenario, which assumed all of the remaining areas targeted for protection are eventually acquired. This approach enabled us to quantify the progress, in terms of reduced risk of extinction, that conservationists have made in protecting target species. It also revealed the limited success these land-acquisition efforts have had in reducing those extinction risks associated with loss of habitat or small geographic ranges. Many species of the Lake Wales Ridge will remain at high risk of extinction even if planned land-acquisition efforts are completely successful. By calculating protection indexes with and without each site for all imperiled species, we also quantified the contribution of each protected area to the conservation of each species, enabling local conservation decisions to be made in the context of a larger (global) perspective. The protection index approach can be adapted readily to other ecosystems with multiple rare and threatened species. 相似文献
192.
Stanger G 《Environmental geochemistry and health》2005,27(4):359-368
An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common
origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further
concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain.
Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and
Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily
redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and
authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above
palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern
Asia. 相似文献
193.
Bauxite residue (red mud) is a hazardous waste generated from alumina refining industries. Unless managed properly, red mud poses significant risks to the local environment due to its extreme alkalinity and its potential impacts on surface and ground water quality. The ever-increasing generation of red mud poses significant challenges to the aluminium industries from management perspectives given the low proportion that are currently being utilized beneficially. Red mud, in most cases, contains elevated concentrations of iron in addition to aluminium, titanium, sodium and valuable rare earth elements. Given the scarcity of iron supply globally, the iron content of red mud has attracted increasing research interest. This paper presents a critical overview of the current techniques employed for iron recovery from red mud. Information on the recovery of other valuable metals is also reviewed to provide an insight into the full potential usage of red mud as an economic resource rather than a waste. Traditional hydrometallurgy and pyrometallurgy are being investigated continuously. However, in this review several new techniques are introduced that consider the process of iron recovery from red mud. An integrated process which can achieve multiple additional values from red mud is much preferred over the single process methods. The information provided here should help to improve the future management and utilization of red mud. 相似文献
194.
Assessing the global zoo response to the amphibian crisis through 20‐year trends in captive collections 下载免费PDF全文
Global amphibian declines are one of the biggest challenges currently facing the conservation community, and captive breeding is one way to address this crisis. Using information from the International Species Information System zoo network, we examined trends in global zoo amphibian holdings across species, zoo region, and species geographical region of origin from 1994 to 2014. These trends were compared before and after the 2004 Global Amphibian Assessment to assess whether any changes occurred and whether zoo amphibian conservation effort had increased. The numbers of globally threatened species (GTS) and their proportional representation in global zoo holdings increased and this rate of increase was significantly greater after 2004. North American, European, and Oceanian GTS were best represented in zoos globally, and proportions of Oceanian GTS held increased the most since 2004. South American and Asian GTS had the lowest proportional representation in zoos. At a regional zoo level, European zoos held the lowest proportions of GTS, and this proportion did not increase after 2004. Since 1994, the number of species held in viable populations has increased, and these species are distributed among more institutions. However, as of 2014, zoos held 6.2% of globally threatened amphibians, a much smaller figure than for other vertebrate groups and one that falls considerably short of the number of species for which ex situ management may be desirable. Although the increased effort zoos have put into amphibian conservation over the past 20 years is encouraging, more focus is needed on ex situ conservation priority species. This includes building expertise and capacity in countries that hold them and tracking existing conservation efforts if the evidence‐based approach to amphibian conservation planning at a global level is to be further developed. 相似文献
195.
A Standard Lexicon for Biodiversity Conservation: Unified Classifications of Threats and Actions 总被引:3,自引:0,他引:3
NICK SALAFSKY††† DANIEL SALZER† ALISON J. STATTERSFIELD‡ CRAIG HILTON-TAYLOR§ RACHEL NEUGARTEN† STUART H. M. BUTCHART‡ BEN COLLEN NEIL COX†† LAWRENCE L. MASTER‡‡ SHEILA O'CONNOR§§ DAVID WILKIE 《Conservation biology》2008,22(4):897-911
Abstract: An essential foundation of any science is a standard lexicon. Any given conservation project can be described in terms of the biodiversity targets, direct threats, contributing factors at the project site, and the conservation actions that the project team is employing to change the situation. These common elements can be linked in a causal chain, which represents a theory of change about how the conservation actions are intended to bring about desired project outcomes. If project teams want to describe and share their work and learn from one another, they need a standard and precise lexicon to specifically describe each node along this chain. To date, there have been several independent efforts to develop standard classifications for the direct threats that affect biodiversity and the conservation actions required to counteract these threats. Recognizing that it is far more effective to have only one accepted global scheme, we merged these separate efforts into unified classifications of threats and actions, which we present here. Each classification is a hierarchical listing of terms and associated definitions. The classifications are comprehensive and exclusive at the upper levels of the hierarchy, expandable at the lower levels, and simple, consistent, and scalable at all levels. We tested these classifications by applying them post hoc to 1191 threatened bird species and 737 conservation projects. Almost all threats and actions could be assigned to the new classification systems, save for some cases lacking detailed information. Furthermore, the new classification systems provided an improved way of analyzing and comparing information across projects when compared with earlier systems. We believe that widespread adoption of these classifications will help practitioners more systematically identify threats and appropriate actions, managers to more efficiently set priorities and allocate resources, and most important, facilitate cross‐project learning and the development of a systematic science of conservation. 相似文献
196.
Li Jinchang 《中国人口.资源与环境(英文版)》2013,11(1):15-20
Abstract This paper analyses the historical reasons that have resulted in the assumption that natural resources have no valuve. As opposed to this assumption, a conception of resource industry is proposed. The paper expounds the basis of the value of resources and explains the significance of the research of resource value theory. It also attempts to determine the relevant factors, methods and formal expressions of pricing resources. 相似文献
197.
198.
ALISON G. BOYER 《Conservation biology》2010,24(2):511-519
Abstract: Understanding the ecological mechanisms that lead to extinction is a central goal of conservation. Can understanding ancient avian extinctions help to predict extinction risk in modern birds? I used classification trees trained on both paleoecological and historical data from islands across the Pacific to determine the ecological traits associated with extinction risk. Intrinsic traits, including endemism, large body size, and certain feeding guilds, were tightly linked with avian extinction over the past 3500 years. Species ecology and phylogeny were better predictors of extinction risk through time than extrinsic or abiotic factors. Although human impacts on birds and their habitats have changed over time, modern endangered birds share many of the same ecological characteristics as victims of previous extinction waves. My use of detailed predictions of extinction risk to identify species potentially in need of conservation attention demonstrates the utility of paleoecological knowledge for modern conservation biology. 相似文献
199.
Abstract: The most comprehensive data on many species come from scientific collections. Thus, we developed a method of population viability analysis (PVA) in which this type of occurrence data can be used. In contrast to classical PVA, our approach accounts for the inherent observation error in occurrence data and allows the estimation of the population parameters needed for viability analysis. We tested the sensitivity of the approach to spatial resolution of the data, length of the time series, sampling effort, and detection probability with simulated data and conducted PVAs for common, rare, and threatened species. We compared the results of these PVAs with results of standard method PVAs in which observation error is ignored. Our method provided realistic estimates of population growth terms and quasi‐extinction risk in cases in which the standard method without observation error could not. For low values of any of the sampling variables we tested, precision decreased, and in some cases biased estimates resulted. The results of our PVAs with the example species were consistent with information in the literature on these species. Our approach may facilitate PVA for a wide range of species of conservation concern for which demographic data are lacking but occurrence data are readily available. 相似文献
200.
桑植红色旅游资源与民族文化整合研究 总被引:2,自引:0,他引:2
谭业 《湖南环境生物职业技术学院学报》2009,15(3):35-38
桑植县是一个民族文化旅游资源独特、红色旅游资源突出和自然景观优美的县域.通过分析桑植县的旅游资源现状,从而构建了桑植县红色旅游资源与民族文化整合的模式,并提出了相应的市场整合策略.参7. 相似文献