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1.
A spotlight on snow leopard conservation in China   总被引:1,自引:0,他引:1       下载免费PDF全文
China holds the greatest proportion of the snow leopard's (Panthera uncia) global range and is central to their conservation. The country is also undergoing unprecedented economic growth, which increases both the threats to the snow leopard and the opportunities for its conservation. In this paper we aim to review published literature (from 1950 to 2014) in English and Mandarin on snow leopard ecology and conservation in China in order to identify thematic and geographic research gaps and propose research priorities. We first retrieved all published items that considered snow leopards in China (n = 106). We extracted from these papers 274 reports of snow leopard presence in China. We then reviewed a subset of papers (n = 33) of this literature, which specifically focused on snow leopard ecology and conservation within China. We introduced a thematic framework that allows a structured and comprehensive assessment of findings. This framework recognizes 4 critical and interrelated topics underpinning snow leopard ecology and conservation: habitat (distribution and protected area coverage); prey (distribution and abundance, predator–prey relationships); human interactions (hunting and trade, livestock interactions and conflicts); and the underlying policy context. Significant gains in knowledge as well as research gaps and priorities are discussed with reference to our framework. The modest quantity and limited scope of published research on the snow leopard in China calls for a continued and intensified effort to inform and support national conservation policies.  相似文献   
2.
试验采用二次回归饱和设计方法,研究了氮、钾、锰、硼肥和芸薹素内酯、乙烯利对甜菜根产量和含糖率的影响,建立了以根产量和含糖率为目标的回归方程。研究结果表明:氮、钾、锰、硼肥和芸薹素内酯、乙烯利的合理配合施用能使甜菜产量明显提高,品质得到显著改善。通过模拟寻优,决选出了根产量67704.46kg/hm2,含糖率22.3%以上的调控措施为:在施用P2O5150kg/hm2基础上,施纯N 119.85kg/hm2,K2O 144.79 kg/hm2,纯Mn 5.26 kg/hm2,纯B 1.16 kg/hm2;叶面喷施BR和ETH,浓度分别为10.42mg/L和225.58mg/L。  相似文献   
3.
试验采用二次回归饱和设计方法,研究了氮、钾、锰、硼肥和芸薹素内酯、乙烯利对甜菜根产量和含糖率的影响,建立了以根产量和合糖率为目标的回归方程。研究结果表明:氮、钾、锰、硼肥和芸薹素内酯、乙烯利的合理配合施用能使甜菜产量明显提高,品质得到显著改善。通过模拟寻优,决选出了根产量67704.46kg/hm2,含糖率22.3%以上的调控措施为:在施用P205150kg/hm2基础上,施纯N119.85kg/hm2,K20144.79kg/hm2,纯Mn5.26kg/hm2,纯B1.16kg/hm2;叶面喷施BIK和ETH,浓度分别为10.42mg/L和225.58mg/L。  相似文献   
4.
Taxa of conservation interest are frequently identified using morphological or ecological characters. These characters are assumed to represent evolutionary importance, population structure and/or phylogenetic relationships in such organisms. We tested this assumption using two species complexes of the moth genus Hemileuca (Saturniidae). Both have populations threatened by habitat loss and need conservation protection. Legislation protects one taxon with apparent ecological differences. We sequenced 624 base pairs of mtDNA from the COI gene for geographically distant populations of the Hemileuca maia species complex and the H. electra species complex. Resultant phylogenies contradict prior assumptions about relationships in both species complexes. The legislatively protected Bog Buckmoth is paraphyletic with widespread H. maia, and its use of a novel hostplant seems to be a local adaptation. Divergent morphology and hostplant use among H. electra subspecies are associated with modest genetic divergence (0.48%). However, a group of unrecognized populations that are morphologically similar and geographically close to H. electra electra have mtDNA that is divergent by an average of 4.1%. There is disagreement regarding prioritization of ecological divergence over neutral genetic distance in conservation. We place ecological variation in a phylogenetic context and recommend that exploration of genetic relationships be undertaken when populations are threatened. Adaptive ecological variation should be evaluated in a phylogenetic context to understand its conservation importance. This study illustrates the importance both of phylogenetic context and the use of independent characters in assessing biodiversity for conservation prioritization.  相似文献   
5.
The need to prioritize species based on their perceived endangerment has led to the development of systems for categorizing and assessing their degree of vulnerability. Systems with divergent biological and geographical scopes can result in conflicting lists of high-priority species, potentially confusing conservationists and hampering the efficient allocation of resources. To assess conservation priorities for North American birds, we compare three priority-setting systems; those of the International Union for the Conservation of Nature (IUCN), NatureServe, and Partners in Flight (PIF). We found highest correspondence among the three systems in the highest and lowest categories of the respective systems with lower levels of correspondence in intermediate categories. We suggest that this is because the systems, while using different formulations of criteria, are based on the major factors known to be correlated with extinction risk. The few examples of species listed as a high conservation priority by one group but not one or both of the others appear to be the result of differences in availability or interpretation of data. Better communication and collaboration among those responsible for compiling the priority lists for each system is needed.A primary difference among the systems was the total number of species identified as conservation priorities. IUCN identified the fewest species (47) and PIF the most (157). This difference is the result of differences in geographic and taxonomic scope of each system. However, when considered as the percent of the total number of taxa evaluated by each system, all systems identified approximately 20% of species as of conservation concern. To reconcile disparate lists, we urge that conservationists use a hierarchical approach that first considers species that meet thresholds for endangerment under global systems, followed by species considered most vulnerable relative to all continental biota.  相似文献   
6.
  1. The freshwater mussel (Unionida) fauna of the Yangtze River is among the most diverse on Earth. In recent decades, human activities have caused habitat degradation in the river, and previous studies estimated that up to 80% of the mussel species in the Yangtze River are Threatened or Near Threatened with extinction. However, a comprehensive and systematic evaluation of the conservation status of this fauna has yet to be completed.
  2. This study evaluated the conservation status of the 69 recognized freshwater mussel species in the middle and lower reaches of the Yangtze River, using the criteria published by the International Union for Conservation of Nature (IUCN). A new method for prioritizing species for conservation was then developed and applied termed Quantitative Assessment of Species for Conservation Prioritization (QASCP), which prioritizes species according to quantifiable data on their distribution and population status, life history, and recovery importance and potential.
  3. IUCN assessments showed that 35 (51%) species in the study region are Threatened or Near Threatened (11 Endangered, 20 Vulnerable, 4 Near Threatened). In addition, 16 species (23%) could not be assessed owing to data deficiency. Key threats to the freshwater mussel biodiversity of the Yangtze River include pollution, habitat loss and fragmentation, loss of access to host fish, and overharvesting of mussels and their host fish. The genera Aculamprotula, Gibbosula, Lamprotula, Pseudodon, Ptychorhynchus, and Solenaia were identified as particularly threatened.
  4. Data availability allowed QASCP assessment of 44 species. Only Solenaia carinata, regionally Endangered under IUCN criteria, achieved the highest QASCP rank, i.e. First Priority. The five species assessed as Second Priority were considered either regionally Endangered (one), Vulnerable (three), or Data Deficient (one) under IUCN criteria. The 23 Third Priority species were assessed as regionally Endangered (two), Vulnerable (15), Near Threatened (two), or Least Concern (four).
  相似文献   
7.
Knowledge gap analyses can be useful to highlight imbalances in research and to improve the distribution of conservation research efforts. We used ISI’s Web of Knowledge (WoK) and BirdLife International’s library catalogue (BLI) to examine the allocation of research effort amongst the extinction-prone island restricted-range birds (RRSs, n = 1321) and the island endemic bird areas and secondary areas (EBAs, n = 108; SAs, n = 58) previously identified by BirdLife International. We found that the distribution of research effort was very uneven across both species and areas. Half of the number of outputs obtained from WoK referred to 3.1% of the island restricted-range bird species and to 4.8% of the endemic bird areas and secondary areas, whereas 52.2% of the species and 34.3% of the areas had no output. The global distribution of research had a strong spatial component, with a limited number of places receiving most of the research efforts (Hawaii, New Zealand, Central America), while many species rich areas were very poorly studied (South East Asia, South Pacific, most Atlantic islands). Research amongst the most threatened RRSs tended to be less biased, with these species having a higher probability of having at least one output from WoK than less threatened species. Given that threats to the conservation of biodiversity are often highly context-dependent, we advocate prioriting the study of poorly known species and regions. Finally, we integrate the knowledge gaps we identify with previously established conservation priorities, in order to prioritize for future conservation research on RRS, EBAs and SAs.  相似文献   
8.
Spatial prioritization techniques are increasingly applied in the design of protected area networks, which are regarded as the cornerstone of nature conservation efforts. These techniques are becoming ever more sophisticated, but are still founded primarily upon biological data. A common assumption made in most spatial prioritizations is that land throughout a planning region is available for acquisition. We interviewed land managers in the Eastern Cape province, South Africa, and mapped their willingness-to-sell their land using a psychometric analytical technique. We examined the, (i) degree to which vegetation type targets are achieved across a planning region, (ii) areal and cost efficiency, and (iii) spatial configuration, of candidate protected areas identified as important for achieving conservation targets. We found that only 10 out of 48 land managers were willing-to-sell their land. Only seven, five and one of the 19 vegetation types, respectively, could achieve their conservation targets of 10%, 30% and 50% when unwilling land managers were removed from the analysis. Assuming unwilling land managers could be convinced to sell if offered a premium price, the cost of acquiring all lands was between 6.20% and 30.67% more expensive than 2006 land prices. Accounting for implementation opportunities and constraints, such as land manager willingness-to-sell, not simply identifying biological priorities, is of fundamental importance for ensuring spatial prioritizations deliver maps with the potential to usefully guide expansion of protected area networks which can be feasibly implemented.  相似文献   
9.
Zoonoses pose a significant burden of illness in North America. Zoonoses represent an additional threat to public health because the natural reservoirs are often animals, particularly wildlife, thus eluding control efforts such as quarantine, vaccination and social distancing. As there are limited resources available, it is necessary to prioritize diseases in order to allocate resources to those posing the greatest public health threat. Many studies have attempted to prioritize zoonoses, but challenges exist. This study uses a quantitative approach, conjoint analysis (CA), to overcome some limitations of traditional disease prioritization exercises. We used CA to conduct a zoonoses prioritization study involving a range of human and animal health professionals across North America; these included epidemiologists, public health practitioners, research scientists, physicians, veterinarians, laboratory technicians and nurses. A total of 699 human health professionals (HHP) and 585 animal health professionals (AHP) participated in this study. We used CA to prioritize 62 zoonotic diseases using 21 criteria. Our findings suggest CA can be used to produce reasonable criteria scores for disease prioritization. The fitted models were satisfactory for both groups with a slightly better fit for AHP compared to HHP (84.4% certainty fit versus 83.6%). Human‐related criteria were more influential for HHP in their decision to prioritize zoonoses, while animal‐related criteria were more influential for AHP resulting in different disease priority lists. While the differences were not statistically significant, a difference of one or two ranks could be considered important for some individuals. A potential solution to address the varying opinions is discussed. The scientific framework for disease prioritization presented can be revised on a regular basis by updating disease criteria to reflect diseases as they evolve over time; such a framework is of value allowing diseases of highest impact to be identified routinely for resource allocation.  相似文献   
10.
基于DSR模型的煤矿废弃工业广场再开发时序评价体系   总被引:1,自引:1,他引:0  
为提高煤矿废弃工业广场再开发效率,从"城市双修"视角出发,基于驱动力-状态-响应(driving force-state-response,DSR)模型框架,建立由3个一级指标、7个二级指标、16个三级指标组成的煤矿废弃工业广场再开发时序评价体系。以北京京西煤矿为例,采用赋值法进行指标量化分级,利用四象限法对驱动力D、状态S和响应R结果进行耦合处理。结果表明:长沟峪(D=3.818,S=3.848)、大台(D=3.732,S=4.603)和木城涧(D=2.646,S=4.522)划属近期开发;王平(D=4.240,S=3.187)、千军台(D=2.248,S=3.887)和大安山(D=1.792,S=4.39)划属中期开发;安家滩(D=2.118,S=1.464)和花坡根(D=2.798,S=1.907)划属远期开发。该时序评价体系将煤矿废弃工业广场再开发与城市发展紧密结合,以更全面的视角进行时序评价,准确性更高、适宜性更强,为同类型废弃工业广场再开发时序评价提供借鉴参考。  相似文献   
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