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Synopsis The biological diversity and productivity of Philippine coral reefs are threatened by siltation, destructive fishing methods, coral and shell collecting and overfishing. Destructive fishing includes: the widespread, illegal use of explosives; poisons such as sodium cyanide; muro-ami and kayakas fishing; and trawling. The recent decline in catch rates threatens the livelihood of 700 000 near-shore subsistence fishermen who catch 55% of the total landings. The new government under Corazon Aquino wishes to protect the marine environment through the creation of a viable marine conservation management plan, enforcement of existing laws and through cooperation between government, non-government and international agencies to provide education and research. The Department of Agriculture, which has the authority for fisheries, has designated the International Marinelife Alliance as the lead non-government agency involved with fund raising, net-training and finding alternatives to destructive fishing methods.This essay addresses the societal relationships of village fishery to government, aid organizations, and science. Vadim Vladykov always maintained close relationship with fishermen and devoted over a year of his life to helping develop fisheries in Iran.  相似文献   

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Effective conservation management is dependent on accessing and integrating different forms of evidence regarding the potential impacts of management interventions. Here, we explore the application of Bayesian Belief Networks (BBN), which are graphical models that incorporate probabilistic relationships among variables of interest, to evidence-based conservation management. We consider four case studies, namely: (i) impacts of deer grazing on saltmarsh vegetation; (ii) impacts of burning on upland bog vegetation; (iii) control of the invasive exotic plant Rhododendron ponticum; and (iv) management of lowland heathland by burning. Each of these themes is currently a significant conservation issue in the UK, and yet the potential outcomes of management interventions are poorly understood. Through these examples, we demonstrate that BBNs can be used to integrate and explore evidence from a variety of sources, including expert opinion and quantitative results from research investigations. Incorporation of such information in BBNs enables different sources of evidence to be compared, the potential impacts of management interventions to be explored and management trade-offs to be identified. BBNs also offer a highly visual tool for communicating the uncertainty associated with potential management outcomes to conservation practitioners, and they can also be readily updated as new evidence becomes available. Based on these features, we suggest that BBNs have outstanding potential for supporting evidence-based approaches to conservation management.  相似文献   

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Land acquisition is a common approach to biodiversity conservation but is typically subject to property availability on the public market. Consequently, conservation plans are often unable to be implemented as intended. When properties come on the market, conservation agencies must make a choice: purchase immediately, often without a detailed knowledge of its biodiversity value; survey the parcel and accept the risk that it may be removed from the market during this process; or not purchase and hope a better parcel comes on the market at a later date. We describe both an optimal method, using stochastic dynamic programming, and a simple rule of thumb for making such decisions. The solutions to this problem illustrate how optimal conservation is necessarily dynamic and requires explicit consideration of both the time period allowed for implementation and the availability of properties.  相似文献   

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Hyper-herbivory following predator removal is a global issue. Across North America and Europe, increasing deer numbers are affecting biodiversity and human epidemiology, but effectiveness of deer management in heterogeneous landscapes remains poorly understood. In forest habitats in Europe, deer numbers are rarely assessed and management is mainly based on impacts. Even where managed areas achieve stable or improving impact levels, the extent to which they act as sinks or persist as sources exporting deer to the wider landscape remains unknown. We present a framework to quantify effectiveness of deer management at the landscape scale. Applied across 234 km2 of Eastern England, we assessed management of invasive Reeve's muntjac (Muntiacus reevesi) and native roe (Capreolus capreolus), measuring deer density (using thermal imaging distance transects 780 km/year), fertility, neonatal survival, and culling to quantify source-sink dynamics over 2008–2010. Despite management that removed 23–40% of the annual population, 1,287 (95% CI: 289–2,680) muntjac and 585 (454–1,533) roe deer dispersed annually into the wider landscape, consistent with their ongoing range expansion. For roe deer, culled individuals comprised fewer young deer than predicted by a Leslie matrix model assuming a closed population, consistent with age-dependent emigration. In this landscape, for roe and muntjac, an annual cull of at least 60% and 53%, respectively, is required to offset annual production. Failure to quantify deer numbers and productivity has allowed high density populations to persist as regional sources contributing to range expansion, despite deliberative management programs, and without recognition by managers who considered numbers and impacts to be stable. Reversing an unfavorable condition of woodland biodiversity requires appropriate culls across large contiguous areas, supported by knowledge of deer numbers and fertility. © 2013 The Wildlife Society.  相似文献   

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In Lake Svartavasstjønn on the Hardangervidda plateau, a fine-spotted variant of brown trout has been found. The spotted variability shows a classical Mendelian mode of inheritance. In this population genetic variability was found in LDH-5 *, MDH-3 * and MDH-3 *. The fast allele at LDH-5 * had a frequency of 0,913. This is remarkable, as this allele has been found in frequencies above 0.4 in only five out of 50 investigated populations in Norway. The genetic characteristics of brown trout from Lake Svartavasstjønn were compared with 11 other populations sampled from a broad geographical area of Norway. Among these was Lake Setningen, where fine-spotted individuals occur at low frequency. Using a cluster analysis based on eight loci found to be polymorphic in brown trout, we found no indication of a close relationship between the fine-spotted brown trout from Lake Svartavasstjønn and the population in Lake Setningen. During a field survey in 1990 we found that the reproduction of fine-spotted trout in Lake Svartavasstjønn had terminated. The fine-spotted trout represents a valuable but threatened genetic resource, and attempts are carried out to conserve it.  相似文献   

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Aim (1) To determine the relative need for conservation assessments of vascular plant species among the world’s ecoregions given under‐assessed species distributions; (2) to evaluate the challenge posed by the lack of financial resources on species assessment efforts; and (3) to demonstrate the utility of nonlinear mixed‐effects models with both homoscedastic and heteroscedastic error structures in the identification of species‐rich ecoregions. Location Global. Methods We identified the world’s ecoregions that contain the highest vascular plant species richness after controlling for area using species–area relationship (SAR) models built within a mixed‐effects multi‐model framework. Using quantitative thresholds, ecoregions with the highest plant species richness, historical habitat loss and projected increase in human population density were deemed to be most in need of conservation assessments of plant species. We used generalized linear models to test if countries that overlap with highly important ecoregions are poorer compared with others. Results We classed ecoregions into nine categories based on the relative need for conservation assessments of vascular plant species. Ecoregions of highest relative need are found mostly in the tropics, particularly Southeast Asia, Central America, Tropical Andes and the Cerrado of South America, and the East African montane region and its surrounding areas. Countries overlapping with ecoregions deemed important for conservation assessments are poorer as measured by their capita gross national income than the other countries. The nonlinear mixed modelling framework was effective in reducing residual spatial autocorrelation compared with nonlinear models comprised of only fixed effects. In contrasting multiple SAR models to identify species‐rich ecoregions, there was not one SAR model that fitted best across all biomes. Not all SAR models displayed homoscedastic errors; therefore it is important to consider models with both homoscedastic and heteroscedastic error structures. Main conclusions We propose that conservation assessments should be conducted first in ecoregions with the greatest predicted species richness, historical habitat loss and future human population increase. As ecoregions deemed to be important for conservation assessments are located in the poorest countries, we urge international aid agencies and botanic gardens to cooperate with both local and international scientists to fund and implement conservation assessment programmes there.  相似文献   

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Environmental enrichment for laboratory animals has come to be viewed as a potential method for improving animal well-being in addition to its original sense as a paradigm for learning how experience molds the brain. It is suggested that the term housing supplementation better describes the wide range of alterations to laboratory animal housing that has been proposed or investigated. Changes in the environments of animals have important effects on brain structure, physiology, and behavior--including recovery from illness and injury--and on which genes are expressed in various organs. Studies are reviewed that show how the brain and other organs respond to environmental change. These data warrant caution that minor cage supplementation intended for improvement of animal well-being may alter important aspects of an animal's physiology and development in a manner not easily predicted from available research. Thus, various forms of housing supplementation, although utilized or even preferred by the animals, may not enhance laboratory animal well-being and may be detrimental to the research for which the laboratory animals are used.  相似文献   

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Global assessment of conservation threats to several taxonomic groups are urgently needed for species living in regions of the world where field research is curtailed by logistic or economic constraints. For instance, it is now widely recognized that freshwater turtles represent one of the most endangered groups of vertebrates in the world. This situation has been particularly evident with Asian species. Although in Sub-Saharan Africa species are exposed to very similar threats (e.g., intense hunting for food and traditional medicine, habitat loss, collection for the pet trade, etc.), there is no comparable concern in the international conservation community simply because the African species are still too poorly known. Here, I propose a model for analyzing the threat levels to freshwater turtles of Sub-Saharan Africa and I test this model by taking into consideration a series of six risk variables of distribution and ecology. Each variable was categorized into five ranks (0–4) of increasing survival risk. The results, although preliminary, show a great sensitivity of most species. This strongly contrasts with the fact that apart from Malagasy endemics very few species are currently considered as threatened according to IUCN lists. There were clear differences among-families in the major threats. Softshell turtles are especially threatened because their large body size makes them a very good food source for native populations. The single podocnemidid species is also vulnerable, and is particularly sensitive to human hunting for domestic consumption. Concerning the Pelomedusidae, there are several species that are considered by the model as sensitive or highly sensitive to rarity. They are affected by a combination of threats (Extent of distribution in Sub-Saharan Africa, Habitat breadth, Habits, Likeliness of human direct/indirect persecution, and Habitat vulnerability). The conservation implications of these results are discussed.  相似文献   

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DNA sequence data are being produced at an ever-increasing rate. The Bowtie sequence-alignment algorithm uses advanced data structures to help data analysis keep pace with data generation.  相似文献   

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T. L. Fisher 《CMAJ》1968,99(4):180-181
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Academia should be willing to shoulder some of the responsibility for the current dearth of new therapeutic drugs. Our research funding is predicated on the assumption that it will bring value to society, but our emphasis on scientific specialization hinders our ability to add value when a broader vision is required. A solution is the creation of an academy of science generalists motivated to bring together clinical and basic scientists, academia and the private sector, government legislators and industry. A small investment in academic generalists could yield benefits far beyond its modest cost.  相似文献   

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The limits of quantitative manual electromyography (EMG) are discussed. The role of computers in EMG laboratories is at present to imitate or replace the physician performing the test, extending his memory, to gather valuable information which cannot be obtained in a conventional way or, on the contrary, to delete the redundant information. The difficulties in standardizing the parameters of a single motor unit action potential (MUAP) are mainly related to the complexity of the EMG signal and its variability, particularly in pathological states. A computer-aided quantification of interference pattern is presented. The novel methods of examination applied in computerized EMG laboratories are discussed. The scope and limits of computer-aided EMG should be taken into action potential (MUAP) are mainly related to the complexicity of the EMG be accepted are listed.  相似文献   

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