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21.
The IUCN Red List is the most useful list of species that are at risk for extinction worldwide, as it relies on a number of objective criteria. Nevertheless, there is a taxonomic bias that excludes species with small body sizes, narrow distribution ranges and low dispersal abilities, which constitute the vast majority of the planet’s biota, particularly local endemics.By evaluating each IUCN criterion separately, we (i) identify the shortcomings for invertebrate applications, (ii) explain how risk categories may be wrongly applied due to inapplicable and/or misleading thresholds, (iii) suggest alternative ways of applying the existing criteria in a more realistic way and (iv) suggest possible new criteria that were not considered in the current evaluation framework but that could allow a more comprehensive and effective assessment of invertebrates.By adapting the criteria to rely more explicitly on the Area of Occupancy and the Extent of Occurrence, their respective trends and by using ecological modelling methods, the criteria’s applicability would be increased. The change in some thresholds or, eventually, the creation of sub-categories would further increase their adequacy. Additionally, co-extinction could be introduced as an explicit part of the classification process.As a case study, we evaluated 48 species of Azorean arthropods and Iberian spiders according to the current criteria. More than one-quarter (27%) of all evaluated species were classified as Critically Endangered, 19% as Endangered, 6% as Vulnerable and 8% as Least Concern. The remaining 40% did not have enough data to reach a classification.  相似文献   
22.
利用中国引文数据库的引文检索功能,统计了《兰台世界》(2000年-2009年)10年发文被51情况.分别从论文被引年代分布、频次分布、被引期刊分布、高频被引论文分布和基金论文被引分布5个方面进行了分析,揭示了《兰台世界》研究的现状。  相似文献   
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  • 1. Maintaining ecological processes that underpin the functioning of marine ecosystems requires planning and management of marine resources at an appropriate spatial scale.
  • 2. The Great Barrier Reef World Heritage Area (GBR) is the world's largest World Heritage Area (approximately 348 000 km2) and second largest marine protected area. It is difficult to inform the planning and management of marine ecosystems at that scale because of the high cost associated with collecting data. To address this and to inform the management of coastal (approximately 15 m below mean sea level) habitats at the scale of the GBR, this study determined the presence and distribution of seagrass by generating a Geographic Information System (GIS)‐based habitat suitability model.
  • 3. A Bayesian belief network was used to quantify the relationship (dependencies) between seagrass and eight environmental drivers: relative wave exposure, bathymetry, spatial extent of flood plumes, season, substrate, region, tidal range and sea surface temperature. The analysis showed at the scale of the entire coastal GBR that the main drivers of seagrass presence were tidal range and relative wave exposure. Outputs of the model include probabilistic GIS‐surfaces of seagrass habitat suitability in two seasons and at a planning unit of cell size 2 km×2 km.
  • 4. The habitat suitability maps developed in this study extend along the entire GBR coast, and can inform the management of coastal seagrasses at an ecosystem scale. The predictive modelling approach addresses the problems associated with delineating habitats at the scale appropriate for the management of ecosystems and the cost of collecting field data. Copyright © 2010 John Wiley & Sons, Ltd.
  相似文献   
25.
通过参加国际林联第24届世界林业大会, 结合会议论文和现场报告等资料可以看出, 森林和水不仅可以提供生态产品和服务, 而且还存在相互作用。研究森林和水的相互作用对于理解陆地生态系统功能、保护环境和应对气候变化具有重要意义。文中在了解全球森林和水相互作用研究现状的基础上, 总结森林与水研究的趋势和热点问题, 重点阐述在生态水文认知、干旱适应综合研究、土地利用变化与生态水文过程、森林和水管理及其生态系统服务等方面的研究进展, 以期借鉴国际森林和水生态系统保护、研究和管理理念, 拓宽我国生态水文及相关领域的研究思路。  相似文献   
26.
重点分析了麦积山石窟的文化遗产资源特征,并对照《世界遗产公约操作指南》的标准,论证了麦积山石窟符合《世界自然与文化遗产保护公约》标准的要求,完全具备申报世界遗产的条件。  相似文献   
27.
李俊  刘琨 《安徽农业科学》2011,39(25):15467-15470
以邛崃城北区打造世界现代田园城市为例,分析了田园城市的概念、邛崃市的区位概况以及发展现状,在分析了邛崃市旅游区位优势的前提下强调了对城市风貌进行综合部署的重要意义,进而从风貌塑造策略、生态景观策略、绿地系统结构方面阐述了邛崃市城北新区概念规划的策略方针,强调整体风貌应该以"城在田中,园在城中"为指导,注重生态组园与聚合组团并存,突出生态景观富集区的资源优势。在风貌塑造方面强调统一性、生态性、地方性、特色性,并在特色营造方面,在田园城市示范线、居住风貌、滨水岸线打造3个方面展开了细致探讨,强调在建设世界现代田园城市的过程中,应该理清城市形象主线,遵从文化,处理好城市与乡村、人与环境、功能与形象之间的关系,打造宜居的生态城市场所,保护环境、挖掘城市特色、塑造城市形象。  相似文献   
28.
Cottonseed protein has the potential to increase the world's food supply while decreasing the incidence of malnutrition among the world's hungry. Nutritionally, cottonseed flour compares favorably to other animal and vegetable protein sources, as it is low in fat and contains a substantial amount of high biological value protein. Animal studies, as well as human research, using gossypol-free glandless cottonseed flour have shown that cottonseed protein promotes growth, increased weight gain, and a positive nitrogen balance. Cottonseed protein food products have been shown to be a healthy addition to the diets of children, college-age women, and the elderly. With its light color and bland flavor, cottonseed has many uses in the food processing arena. Baked goods, snack foods and candy, as well as pet and livestock feed are just a few successful products developed utilizing cottonseed protein.  相似文献   
29.
通过对利川市世界银行贷款第2期、第3期的项目造林,被划入"天保工程"区后的现状进行调查,找出问题,提出解决方案,仅供参考。  相似文献   
30.
国内外农药加工现状   总被引:4,自引:1,他引:3  
综述了国内外农药加工的新动向以及农药制剂研究的发展现状,探讨了今后农药制剂的开发课题和农药加工业的发展前景。  相似文献   
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