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1.
余超波 《植物学报》2001,18(4):500-504
本文报道了高贵山珍稀濒危重点保护木本植物21种(亚种),其中国务院新近公布的I级重点保护植物1种,Ⅱ级重点保护植物6种,省级重点保护植物8种,其他珍稀植物6种,分析了高贵山珍稀濒危重点保护木本植物的区系特点,指出了高贵山珍稀濒危树木在湖北珍稀濒危植物保护中的重要地位,提出了保护高贵山珍稀濒危木本植物的建议和措施。  相似文献   

2.
河南大别山珍稀濒危植物与保护   总被引:16,自引:1,他引:15  
研究了河南大别山珍稀濒危植物的种类组成,区系成分,生态地理分布。结果表明本区有珍稀濒危植物18科,22属,24种,其中国家二级保护植物9种,三级保护植物15种,属华南热带植物区系成分的有3种,华东亚热带植物区系成分的有8种,华中亚热带植物区系成分的有10种,全国广布种3种,根据大别山植物的现状提出了本区珍稀濒危保护植物的保护措施,系统清查本区的珍稀濒危植物,建立技术档案,就地建立珍稀濒危植物保育基地;建立以珍稀濒危植物为主体的生态园林示范工程。  相似文献   

3.
深圳的珍稀濒危植物   总被引:9,自引:1,他引:8  
深圳自然分布有国家珍稀濒危植物20种,其中广东省重点保护植物1种;在调查其分布现状、濒危原因的基因上,提出了一批应加以保护的植物种类和建议。  相似文献   

4.
江西稀有濒危植物资源及其保护   总被引:9,自引:0,他引:9  
据调查统计,江西自然分布有国家稀有濒危植物74种,比《中国珍稀濒危植物》记载本省的种类(48种)增加了26种,是华东濒危植物资源丰富的省份之一。本文论述了江西稀有濒危植物的地理分布、区系特征及保护现状,它们具有组成丰富、区系复杂、起源古老、成分多特有、分布局限和生态脆弱等特点。在分析稀有植物濒危原因和本省保护区建设情况的基础上,提出了保护稀有濒危植物资源的建议。  相似文献   

5.
色季拉山珍稀濒危植物优先保护研究   总被引:1,自引:0,他引:1  
以西藏色季拉山16科、49属、87种珍稀濒危植物为研究对象,通过对其评价指标的定量化和权重分配处理,求得物种的“濒危系数”和“优先保护值”,确定了物种濒危等级和优先保护等级.结果表明:(1)西藏色季拉山的87种植物中有1种处于极危状态,13种处于濒危状态,55种处于易危状态,18种处于近危状态.(2)西藏色季拉山有一级保护植物23种,二级保护植物53种,三级保护植物11种.(3)该研究结果与各种保护植物名录的濒危等级和优先保护级别存在较大差异,大部分植物在本区受威胁程度加强,应引起足够重视.  相似文献   

6.
鄂北高贵山珍稀濒危木本植物调查研究   总被引:5,自引:0,他引:5  
余超波 《植物学通报》2001,18(4):500-504
本文报道了高贵山珍稀濒危重点保护木本植物21种(亚种),其中国务院新近公布的I级重点保护植物1种,II级重点保护植物6种,省级重点保护植物8种,其他珍稀植物6种,分析了高贵山珍稀濒危重点保护木本植物的区系特点,指出了高贵山珍稀濒危树木在湖北珍稀淑危植物保护民中的重要地位,指出了保护高贵山珍烯濒危木本植物的建议和措施。  相似文献   

7.
中国稀有濒危植物分级问题的微机定量研究   总被引:4,自引:0,他引:4  
风险程度(濒然度)分级问题是稀有濒危植物优先保护评价中一个亟待解决的重要难题。应用改进了的二级模糊综合评判为基础的系统模式识别,定量研究了中国稀有濒危植物濒危等级;用动态的系统分级阈值,裁定100个待评种等级之归属。  相似文献   

8.
江西省珍稀濒危植物调查研究   总被引:3,自引:1,他引:2  
综合《中国珍稀濒危保护植物名录》(第1册)和《国家重点保护野生植物名录》(第1批),江西省有珍稀濒危植物95种。它们具有种类多、起源古老、分布范围广、区系地理成分复杂等特点,并且绝大多数具有重要的经济价值和科研价值。在探讨江西省珍稀濒危植物致危机制的基础上,提出了保护建议。  相似文献   

9.
为制定江西庐山国家级自然保护区珍稀濒危植物的保护策略,采用濒危系数、遗传系数及物种价值系数等评价指标对58种珍稀植物的濒危程度和优先保护顺序进行评估。结果表明,自然保护区珍稀植物的综合评价值(VS)为0.153~0.742,濒危等级为安全的11种,占该区珍稀保护植物总数的19%;稀有的28种(48%);渐危的18种(31%);濒危的1种(2%)。优先保护顺序为Ⅰ级的8种,占该区珍稀保护植物总数的14%,急需保护;Ⅱ级的22种(38%),需要保护;Ⅲ级的23种(40%),可以一般保护;IV级的5种(8%),较为安全。生境破坏和人为干扰是该区珍稀植物保护面临的主要威胁。  相似文献   

10.
三峡库区珍稀濒危植物资源保护对策   总被引:7,自引:0,他引:7  
分析了三峡库区珍稀濒危植物资源现状。针对三峡库区珍稀濒危植物资源所面临的各种生态和社会问题,提出了相应的保护对策。这些对策包括对部分珍稀濒危植物实行迁地保护,加强种质资源保护,建立珍稀特有植物的专项或综合保护区,建立珍稀特有植物资源的环境监测体系。加强科研和宣教工作,保护珍稀濒危植物的现有生境和恢复植被等。  相似文献   

11.
Prioritizing geographic areas for conservation attention is important – time and money are in short supply but endangered species are not – and difficult. One popular perspective highlights areas with many species found nowhere else ( Myers et al. 2000 ). Another identifies areas that contain species with fewer close relatives elsewhere ( Faith 1992 ). One might characterize the first as focusing on geographic, and the second on phylogenetic, rarity. To the extent that geographically rare species are at greater risk of extinction ( Gaston & Fuller 2009 ), and that phylogenetically rare species contribute disproportionally to overall biodiversity ( Crozier 1997 ), it would seem reasonable to formally integrate the two approaches. In this issue, Rosauer et al. (2009) do just that; their elegant combined metric pinpoints areas missed out when the two types of rarity are looked at in isolation.  相似文献   

12.
On sampling and the estimation of rare errors   总被引:1,自引:0,他引:1  
COX  D. R.; SNELL  E. J. 《Biometrika》1979,66(1):125-132
  相似文献   

13.
The results of a large screening for the transferrin polymorphism in five different areas of Italy (3099 cases) are given. Frequencies of common types were similar to those of already known Caucasian populations. Among rare types TfB were more frequently observed than TfD. Evidence is given for the existence of the TfC6 allele in Caucasians. A family group analysis of some rare types was done.  相似文献   

14.
Two striking fungi, isolated from soils from the island of Hachijo-jima in Japan, are described and illustrated. One of these represents a new species ofTalaromyces (Ascomycetes), for which the nameTalaromyces hachijoensis is proposed. The new species is distinctive among all other recognized species in its restricted growth on common media, yellow ascomata characterized by asci developing in chains, striate ascospores, and the absence of an anamorph. The other isHeterocephalum taiense, a rare hyphomycete which has only previously been recorded from lvory Coast soil and probably from Panama soil.  相似文献   

15.
Two stichaeid fishes were collected off the Okhotsk coast of Hokkaido in Japan. One represents a new species,Stichaeus fuscus, which differs from all other species of this genus in meristics, color pattern, shape of the pelvic fin, and body proportions. The other species is identified asSoldatovia polyactocephala (Pallas) and is redescribed.  相似文献   

16.
17.
珍稀濒危植物夏蜡梅的减数分裂观察   总被引:5,自引:2,他引:3  
首次研究了夏蜡梅小孢子母细胞的减数分裂过程,并观察了花粉粒育性. 后期Ⅰ,末期Ⅰ和后期Ⅱ均观察到少量染色体异常行为的发生,但整个过程基本正常.花粉粒活性也大都正常.人为的因素可能是夏蜡梅濒危狭域的原因.  相似文献   

18.
Microbial communities have a key role in the physiology of the sponge host, and it is therefore essential to understand the stability and specificity of sponge–symbiont associations. Host-specific bacterial associations spanning large geographic distance are widely acknowledged in sponges. However, the full spectrum of specificity remains unclear. In particular, it is not known whether closely related sponges host similar or very different microbiota over wide bathymetric and geographic gradients, and whether specific associations extend to the rare members of the sponge microbiome. Using the ultra-deep Illumina sequencing technology, we conducted a comparison of sponge bacterial communities in seven closely related Hexadella species with a well-resolved host phylogeny, as well as of a distantly related sponge Mycale. These samples spanned unprecedentedly large bathymetric (15–960 m) gradients and varying European locations. In addition, this study included a bacterial community analysis of the local background seawater for both Mycale and the widespread deep-sea taxa Hexadella cf. dedritifera. We observed a striking diversity of microbes associated with the sponges, spanning 47 bacterial phyla. The data did not reveal any Hexadella microbiota co-speciation pattern, but confirmed sponge-specific and species-specific host–bacteria associations, even within extremely low abundant taxa. Oligotyping analysis also revealed differential enrichment preferences of closely related Nitrospira members in closely related sponges species. Overall, these results demonstrate highly diverse, remarkably specific and stable sponge–bacteria associations that extend to members of the rare biosphere at a very fine phylogenetic scale, over significant geographic and bathymetric gradients.  相似文献   

19.
20.
《Trends in genetics : TIG》2023,39(5):415-429
Herein we focus on connections between genetics and some central disorders of hypersomnolence – narcolepsy types 1 and 2 (NT1, NT2), idiopathic hypersomnia (IH), and Kleine–Levin syndrome (KLS) – for a better understanding of their etiopathogenetic mechanisms and a better diagnostic and therapeutic definition. Gene pleiotropism influences neurological and sleep disorders such as hypersomnia; therefore, genetics allows us to uncover common pathways to different pathologies, with potential new therapeutic perspectives. An important body of evidence has accumulated on NT1 and IH, allowing a better understanding of etiopathogenesis, disease biomarkers, and possible new therapeutic approaches. Further studies are needed in the field of epigenetics, which has a potential role in the modulation of biological specific hypersomnia pathways.  相似文献   

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