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1.
根据CITES公约附录保护与管制木材种类名录,对云南处于濒危管制的木材树种资源现状进行研究。结果表明,全省被列入CITES公约的木材共有8种(类),其中附录Ⅱ有5种(类),附录Ⅲ有3种(类)。  相似文献   
2.
Methods of assessing extinction risk in marine fishes   总被引:1,自引:0,他引:1  
The decline and disappearance of species from large parts of their former geographical range has become an important issue in fisheries ecology. There is a need to identify which species are at risk of extinction. The available approaches have been subject to considerable debate – particularly when applied to commercially exploited species. Here we have compiled methods that have been used or may be used for assessing threat status of marine organisms. We organize the methods according to the availability of data on the natural history, ecology and population biology of species. There are three general approaches to inferring or assessing extinction risk: (i) correlative approaches based on knowledge of life histories and ecology; (ii) time‐series approaches that examine changes in abundance; and (iii) demographic approaches based on age‐ or stage‐based schedules of vital rates and fisheries reference points. Many methods are well suited to species that are highly catchable and/or have relatively low productivity, but theory is less well developed for assessing extinction risk in species exhibiting narrow geographical distributions or ecological specialization. There is considerable variation in both definitions of extinction risk and the precision and defensibility of the available risk assessment methods, so we suggest a two‐tiered approach for defining and assessing extinction risk. First, simple methods requiring a few easily estimated parameters are used to triage or rapidly assess large numbers of populations and species to identify potentially vulnerable populations or species. Second, the populations and species identified as vulnerable by this process can then be subject to more detailed and rigorous population analysis explicitly considering sources of error and uncertainty.  相似文献   
3.
The extraction of coral reef organisms for the aquarium and curio trade is reported to be contributing to coral reef degradation. The total international trade and associated impacts are unknown, because data are collected only for organisms listed on Appendix II of CITES, which include stony corals, antipatharians and giant clams. CITES data indicate that trade in live stony coral and reef substrate (live rock) increased by 15–30% each year during the 1990s, with most exports since 1992 from Indonesia and Fiji. Overall, 19% of all stony coral traded (by item) from 1985 to 1997 was live; 71kern-1pt% of this was traded between 1993 and 1997 (52% of total trade). Although tracking trade using information from the CITES Trade Database provides limited information (e.g., coral is reported to genus, and volume is reported by item or weight), the CITES mechanism promotes the development of strategies to protect resources. In response to CITES requirements, Indonesia developed a management plan for sustainable harvest of corals, but not for non-CITES listed species such as soft corals and fishes. Trade in hard and soft coral provides revenue for developing countries; however, in order to be of lasting value the industry must be developed with a conservation ethic. This requires support for international programs such as CITES, management plans for sustainable harvest, and improved enforcement.  相似文献   
4.
  • 1. The implications of shrinkage associated with desiccation and ethanol preservation for seahorses (genus Hippocampus) were investigated using Hippocampus guttulatus (European long‐snouted seahorse) as a model. Specifically, this research addressed the implications of preservation for taxonomy and life history studies and the application of minimum size limits (MSL) for managing seahorse trade.
  • 2. In 2004, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) listed all seahorse species on its Appendix II, and recommended a 10 cm MSL as an interim means of ensuring sustainable international trade. Inconsistencies in seahorse measurement methods and repeatability posed challenges for applying the MSL. Moreover, the shrinking effect of desiccation on body length observed in other fish was assumed to be negligible for seahorses because of their high degree of ossification.
  • 3. Changes in seahorse sizes were measured following immersion in ethanol and desiccation. H. guttulatus shrank on average by 0.1–2.3% when preserved in ethanol and 3.0–6.4% when dried, depending on the trait measured. Similar trends were observed in a sample of H. kuda (yellow seahorse). Specimen posture during drying, and measurement methods also influenced estimates of size.
  • 4. Based on the shrinkage observed, 14–44% of captured seahorses that are dried could shrink to below the recommended MSL, even if all seahorses were longer than the MSL at capture. This demonstrates that small changes in body lengths can have significant implications for trade of species managed with size limits.
  • 5. Recommendations are to (1) standardize seahorse measurement methods, (2) consider the effects of preservation and measurement technique on body lengths, and apply appropriate corrections in comparative studies and when developing fisheries management strategies, and (3) adjust size limits at the point of capture to ensure retained seahorses comply with the CITES recommended MSL.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
5.
使用2009—2015年《濒危野生动植物种国际贸易公约》(CITES)管制树种贸易数据分析我国进口CITES管制树种的种类、来源国、贸易目的和树种来源。研究结果显示,中国进口CITES管制树种呈现出进口种类集中、进口树种数量和来源国不断增加的趋势,且进口CITES管制树种基本来源于野外并用于商业性用途。针对贸易现状,文中从保护野生树种资源的角度对进一步规范CITES贸易活动提出了针对性建议。  相似文献   
6.
CITES附录中哺乳动物注释的使用分析   总被引:1,自引:0,他引:1  
《濒危野生动植物种国际贸易公约》经过45年的发展和演进,在正文与附录的基础上,形成了决议、决定、注释等相互交织的复杂规则。作为对附录执行的解释和细化,附录注释的功能和作用越来越凸显出来。对附录注释的研究和重视程度不够、理解片面甚至忽略,是大多数缔约方在过往履约工作实践中确实存在的现象。本文系统介绍了公约附录注释体系,初次尝试从6个角度对哺乳动物注释的作用进行了分析,在充分理解的基础上提出履约应重视对CITES附录注释的解读和使用,从而实现适应性管理。  相似文献   
7.
The application of genetics for the management of natural resources is expanding, and within this field, DNA registers will play an increasing role. The Norwegian minke whale DNA register, established in 1996, was designed primarily as a control system to detect any attempts at illegal trade of products derived from other stocks of minke whale, or other whale species, under cover of the legal Norwegian harvest originating from the Northeast Atlantic. The register contains genetic data for 7644 of 7751 whales landed in the period 1997–2010. Profiles are established from sequencing part of the mtDNA control region, analysis of 10 STRs and a sex‐determining marker. Probabilities of genotypes matching between two randomly selected whales are 6.0?04 and 3.0?08 for five and eight of the STR loci, respectively. This permits verification of traded whale products via match to the register. The register has also been used in a number of ad hoc scientific studies resulting through the accumulation of genetic, demographic and biological data. Here, we review the register’s logistics, specifications and evaluate the potential to apply similar registers to control the exploitation of other marine species.  相似文献   
8.
Myanmar is home to Asiatic black bears and sun bears. We gained insight into illegal hunting and trade of these species in and out of Myanmar through conversations with 40 self-declared bear poachers. All respondents were males who typically killed or caught one to three bears a year, mostly by setting snares. There was a preference for Asiatic black bear. Perceptions were that bears were less abundant now than 5 years ago, but it was not more arduous to obtain one. Most poachers (75%) consumed less valuable parts and sold the remainder, whereas others trapped only to sell. Preferred tradable parts were gall bladder, meat, and paws. Chinese nationals or Burmese of Chinese descent were mentioned as playing key roles (ordering, buying, selling) in trade. Instead of focusing on poachers, we recommend that authorities focus on disrupting trade networks and markets. Cooperation with neighboring countries, especially China, is needed to stem the flow of bear parts.  相似文献   
9.
澜沧江自然保护区珍稀濒危保护植物研究   总被引:1,自引:0,他引:1  
谢凤瑞  杜凡  王娟  和菊  丁涛 《安徽农业科学》2010,38(26):14562-14565,14570
澜沧江自然保护区为国际著名河流澜沧江的直接汇水区。采用样地调查、线路调查并结合询问的方法,对保护区的珍稀濒危保护植物进行种类、分布特点、生境、所在群落特征、种群数量、更新及人为利用状况和受威胁程度等方面的调查。发现国家级保护植物6种、我国珍稀濒危植物6种、云南省级保护植物11种,以及CITES公约附录Ⅱ的保护植物(均为兰科植物)33种。保护区海拔为1500~3426m,上述植物的物种丰富度随海拔梯度变化的规律表现出典型的单峰曲线特征;在海拔2200~2500(2600)m达到峰值,占55种植物的73%。针对该保护区内珍稀濒危物种的威胁现状,认为:中低海拔段(1500~2200m)人为影响显著,适生生境减少和退化,要重点进行植被的恢复和加强保护管理;中海拔段2200~2500(2600)m,人为影响较少,主要是加强宣传和巡护管理;海拔2500(2600)m以上的较高海拔段,管理上注意控制放牧,并杜绝火灾的发生。云南红豆杉、石斛、水青树和合果木等5种种群数量最少且受人为干扰最严重,要优先开展种群调查和监测,采集不同的种源进行人工扩繁,保持和扩大它们的野生居群数量,维持和丰富其遗传多样性。  相似文献   
10.
Prized for their dense, rot-resistant wood, Tabebuia impetiginosa and T. serratifolia (vernacular name = ipê) are among the most valuable Amazonian timbers. We analyzed the geographical extent, spread and trajectory of ipê logging in Brazilian Amazonia, and evaluated harvest pressure on this forest resource. We also examine Tabebuia population response to reduced-impact logging, a more ecologically benign alternative to destructive conventional harvest practices in Amazonia. Based on eight years of population monitoring at multiple sites in the eastern Brazilian Amazon, we project second harvest ipê yields in forests logged using RIL under legally allowable (90% of commercial stems) and reduced (70%) harvest intensities.In recent years ipê harvests have declined or ceased in the majority of old logging frontiers in eastern Amazonia while spreading to new logging frontiers in central and southwestern Amazonia. With current timber market prices, transportation infrastructure and harvesting costs, logging of ipê would be profitable in an estimated 63% of the Brazilian Amazon; in the more remote logging frontiers only logging of ipê and a few other high-value timbers is currently profitable. All populations of T. impetiginosa and T. serratifolia in northeastern forests showed drastic population declines over multiple RIL harvests in simulations, with no indication of population recovery over the long term. We conclude from study of Tabebuia populations in eastern Amazonia and modeling of response to logging that these two species are endangered by logging activity and merit additional protection under forest legislation.  相似文献   
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