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1.
井冈山地区珍稀濒危植物及其生存状况   总被引:1,自引:0,他引:1  
开展国家珍稀濒危保护植物的考察、研究,对探讨区域生物多样性的性质、评价生态环境的状况和质量,提出适当的自然保护、管理对策等,均具有重要的指导意义.本文调查研究了井冈山地区珍稀濒危植物的种类、数量、分布、生长状况以及重要木本植物的群落特征,探讨了珍稀濒危植物的系统学与生物地理学特征.结果表明,井冈山地区有濒危苔藓植物2种,各类珍稀濒危野生维管植物199种.其中被《世界自然保护联盟濒危物种红色名录》收录50种,被《中国物种红色名录》收录160种,被《国家重点保护野生植物名录(第一批)》收录49种,被《濒危野生动植物种国际贸易公约附录》收录90种.本区珍稀濒危植物的种类和数量大体上与峨眉山相当,而远高于武夷山和太白山,在系统学与生物地理学上有重要意义,具有极高的保护价值.本区保存有较大面积的以珍稀濒危植物为优势种的群落,如资源冷杉(Abies beshanzuensis vat.ziyuanensis)、华榛(Corylus chinensis)、白豆杉(Pseudotaxus chienii)、南方红豆杉(Taxus wallichiana var.mairei)、福建柏(Fokienia hodginsii)、穗花杉(Amentotaxus argotaenia)、闽楠(Phoebe bournei)、马醉木Pieris japonica)、井冈山杜鹃(Rhododendron jinggangshanicum)等群落.  相似文献   

2.
甘什岭保护区是海南岛南端的热带森林保护区,植物区系特殊,特有植物无翼坡垒(Hopea exalata)在这里成片分布。2010年保护区范围得到调整,为全面了解保护区内珍稀濒危植物的分布状况,作者于2010–2012年对植物物种多样性进行了系统的野外调查,并对其保护等级进行评估,以期为我国热带珍稀濒危植物的保护提供依据。结果表明:保护区内共分布有野生珍稀濒危植物106种。其中,《国家重点保护野生植物名录》第一批和第二批(讨论稿)收录43种,《中国植物红皮书》收录19种,《IUCN濒危物种红色名录》收录29种,《中国物种红色名录》收录61种,《濒危野生动植物种国际贸易公约》附录收录34种,《海南省省级重点保护野生植物名录》收录76种。保护区内珍稀濒危植物种类占植物种类总数的比例较附近的五指山、鹦哥岭、尖峰岭三大国家级雨林保护区略低。根据这些种类的分布状况,分为罕见种(3种)、稀有种(15种)、偶见种(63种)和常见种(25种)。特有性分析发现,海南特有种有22种(包括2种甘什岭特有种),中国特有种有13种。根据我们的评估结果,建议将46种植物的保护等级提升或增补于保护范围。  相似文献   

3.
以《中国珍稀濒危保护植物名录》、《中国植物红皮书》、《国家重点保护野生植物名录(第一批)》、《中国物种红色名录》、《中国生物多样性红色名录(高等植物卷)》、《内蒙古珍稀濒危保护植物名录》和《内蒙古珍稀濒危植物图谱》中127种内蒙古珍稀濒危植物为研究对象,通过资料收集及专家咨询,构建了内蒙古珍稀濒危植物受威胁等级、优先保护评估体系.建立了濒危系数、遗传价值系数、利用价值系数、生境系数、繁殖系数5项准则,准则下共设17个指标;运用层次分析法确定指标体系权重,计算出珍稀濒危植物濒危等级及优先保护级别.结果表明: 极危种2种、濒危种13种、易危种37种、近危种44种、无危种31种,分别占总数的1.6%、10.2%、29.1%、34.7%、24.4%.其中,受威胁种(极危、濒危和易危种)共52种,占总种数的40.9%.一级保护植物35种、二级保护植物72种、三级保护植物20种,分别占总数的27.6%、56.7%、15.8%.本评估结果与《中国生物多样性红色名录(高等植物卷)》、《内蒙古珍稀濒危保护植物名录》相比,有75种植物的濒危等级和62种植物的保护级别发生了变化.其中新增了9种植物的濒危等级评估和32种植物的保护级别.  相似文献   

4.
为了探究鄂西北地区珍稀濒危植物及其多样性空间分布与该区域地理环境的关系,于2007-2017年先后对鄂西北8个自然保护区的植物资源进行了调查,对其种类组成、地理成分、生活型及物种多样性的空间分布特征进行研究。结果显示:(1)鄂西北珍稀濒危植物共有262种,隶属于62科149属;(2)该区域珍稀濒危植物地理成分与生活型谱具有地域过渡性和多样性;(3)鄂西北地区珍稀濒危植物的物种丰富度峰值出现在海拔900~1700 m区段,物种丰富度与海拔区段间具有显著的二次方程关系:y=-0.5107x~2-12.43x+7.3111(R~2=0.7867,P=0.04);(4)不同空间尺度下,物种Shannon-Wiener多样性指数(H_D)、均匀度指数(ED)、Margalef多样性指数(K_D)随空间尺度的变化均呈幂函数关系,其相关系数分别为R~2=0.7303 (H_D)、R~2=0.8858(E_D)、R2=0.9805(KD)。研究表明H_D、E_D、K_D值的变化幅度可能与该区域地理环境的变化有关。目前砍伐毁林和过度采挖是该地区珍稀濒危植物最大的威胁因素,建议从珍稀濒危植物物种多样性分布与地理环境特性相结合的角度加强管理,为区域珍稀濒危植物的科学恢复提供支撑。  相似文献   

5.
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   

6.
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   

7.
海南鹦哥岭自然保护区的珍稀濒危植物与保育   总被引:1,自引:0,他引:1  
对鹦哥岭的珍稀濒危植物进行野外调查表明,本区共有野生分布的珍稀濒危植物79种,隶属于47科71属。其中属于1999年国家重点一级保护4种,如海南苏铁(Cycas hainansis)、坡垒(Hopea hainansis)、台湾苏铁(Cy-cas taiwaniana)和伯乐树(Bretschneidera sinensis),国家二级保护14种。建议将18种列入国家保护名录中,20种列入省级保护名录,其中有30种为海南特有种。鹦哥岭珍稀濒危植物面临的威胁主要有原始森林面积的减少、人为毁林开荒和分布区限制。针对珍稀濒危植物的现状和受到的威胁,提出了应重点加强保护的6个地点及相应的保护对策和建议。  相似文献   

8.
河南大别山区野生珍稀濒危植物资源初步研究   总被引:2,自引:1,他引:1  
论述了河南大别山区野生珍稀濒危植物资源现状、地理分布和生境特点,分析了珍稀濒危植物产生的原因,提出了保护和开发利用珍稀濒危植物资源相应对策.  相似文献   

9.
对南京市珍稀濒危植物的种类、分布、生境及濒危原因进行了调查和分析,并对主要种类进行了就地保存、迁地保存或就地-迁地保存实验。调查发现,南京市共有珍稀濒危植物17种1变种,隶属9科17属,主要分布在丘陵山地;人为因素是其濒危的主要原因。对明党参(Changium smyrnioides H.Wolff.)、短穗竹〔Brachystachyumdensiflorum(Rendle)Keng〕及秤锤树(Sinojackia xylocarpa Hu)等种类的保护研究结果表明,采取一定的人为干预措施,可使南京市珍稀濒危植物的种群数量得到有效的保存和恢复。  相似文献   

10.
为加强对罗霄山脉地区珍稀濒危植物的保护和管理, 作者在对该区域的植被和植物区系全面调查的基础上, 针对珍稀濒危植物的组成、种群数量、生存状态等进行了深入调查和评估。结果表明: (1)整体上, 罗霄山脉各类珍稀濒危植物共59科142属279种, 其中: 被IUCN红色名录收录17种, 包括极危种(CR) 2种, 濒危种(EN) 3种, 易危种(VU) 12种; 被《中国生物多样性红色名录: 高等植物卷》收录的共105种, 包括极危种9种, 濒危种33种, 易危种63种; 被《国家重点保护野生植物名录》收录的共257种, 包括Ⅰ级8种, 即银杏(Ginkgo biloba)、资源冷杉(Abies beshanensis var. ziyuanensis)、南方红豆杉(Taxus wallichiana var. mairei)、莼菜(Brasenia schreberi)伯乐树(Bretschneidera sinensis)、细叶石斛(Dendrobium hancockii)铁皮石斛(D. officinale)细茎石斛(D. moniliforme)等, II级249种; 被CITES收录的有71种。(2)在局部区域, 罗霄山脉自北至南由5条中型山脉组成, 其珍稀濒危植物的数量分布由北向南呈现梯级变化, 显示出与该地区植被和植物区系的丰富度和保存状况密切相关, 其中幕阜山脉147种、九岭山脉138种、武功山脉133种、万洋山脉207种、诸广山脉192种。(3)从珍稀濒危植物属种组成看, 保存有大量古老、孑遗和特有的类群, 并且受到气候和地理环境的影响, 其中有单型属19属, 中国特有种129种。本文针对各珍稀濒危植物的生存现状, 提出了按分布区域和濒危性质进行群落监测或适度进行人工干预等保护措施。  相似文献   

11.
大兴安岭林区针叶林的生长方程及火灾林木死亡率   总被引:3,自引:3,他引:0  
本文用随机模拟的方法建立了北方针叶林的生长方程及其受到火灾侵害后的林木死亡率,定量地研究了火灾对这种林分变动的影响.  相似文献   

12.
It is the opinion of the authors of the Comment on Do et al. (2006), that those authors incorrectly interpreted their test results, which are more likely the result of mislabeling of samples or within-laboratory contamination, and that the TSV isolates found in Penaeus vannamei in Korea in 2004 and 2005 did not originate from Hawaii as claimed by the authors, but from a country (or countries) in southeast Asia. Finally, we believe that the authors did not follow proper international guidelines, extend a professional courtesy to the supplier of the disputed shrimp sample, nor take a critical approach in interpreting their own data. It is unfortunate that the authors did not follow through with additional testing, or seek a second opinion from an independent laboratory, before implicating shrimp imported from Hawaii as the source of TSV in Korea.  相似文献   

13.

Background

Many journals now require authors share their data with other investigators, either by depositing the data in a public repository or making it freely available upon request. These policies are explicit, but remain largely untested. We sought to determine how well authors comply with such policies by requesting data from authors who had published in one of two journals with clear data sharing policies.

Methods and Findings

We requested data from ten investigators who had published in either PLoS Medicine or PLoS Clinical Trials. All responses were carefully documented. In the event that we were refused data, we reminded authors of the journal''s data sharing guidelines. If we did not receive a response to our initial request, a second request was made. Following the ten requests for raw data, three investigators did not respond, four authors responded and refused to share their data, two email addresses were no longer valid, and one author requested further details. A reminder of PLoS''s explicit requirement that authors share data did not change the reply from the four authors who initially refused. Only one author sent an original data set.

Conclusions

We received only one of ten raw data sets requested. This suggests that journal policies requiring data sharing do not lead to authors making their data sets available to independent investigators.  相似文献   

14.
本文讨论了一类主要由昆虫自食引起的非线性种群动态模型的稳定性.首先给出确定性模型,并着重讨论其一个特殊情形.通过在参数空间中辨识稳定域的边界,可以相对直观地分析种群动态.对于随机模型,是利用在确定性模型中加入对数尺度下的正态随机项形成的,该模型具有较好的统计性质,便于将现实的非线性时间序列数据引进系统中来.  相似文献   

15.
本文在实际测量数据的基础上,提出一种运用主成分分析的方法对数据进行筛选和匹配,进而对人体和猕猴作典型相关分析,从而得出这种替代是有意义的.  相似文献   

16.
In June of 2000, the U.K. Medical Device Agency recommended the removal of Trilucent implants as a precautionary maneuver in response to reports of local inflammatory reactions. This decision allowed the authors to operate on 115 consecutive patients between June of 2000 and January of 2001. On the preoperative examination, the authors found a very high incidence of rippling (66 percent), whereas capsular contracture was seen in only three patients (2.6 percent). Rippling was significantly more common in patients with subglandular implants. Five implants were found ruptured during the operation. This figure, together with the relative ease of implant breakage at removal, shows a premature deterioration of the implant shell. The authors also comment on implant bleeding, which seems common in this type of breast implant. The authors think that this is a possible cause for the rippling phenomenon, resulting from a reduction of the implant content. On the basis of these findings, the authors conclude that Trilucent implants are associated with a poor cosmetic outcome and a high rate of complications.  相似文献   

17.

Background

The practice of giving certain authors equal credit in original research publications was increasingly common in some specialty. This study aimed to investigate the prevalence and characteristics of designating some authors with equally credited authors (ECAs) in major anaesthesia journals.

Methodology/Principal Findings

The practice of giving authors equal credit was searched and identified in the three major anaesthesia journals between January 1, 2002 and December 31, 2011. Papers with ECAs had a higher proportion of the total number of articles in 2011 versus published in 2002 (Anesthesiology, 8.8% vs. 0.9%; British Journal of Anaesthesia, 8.8% vs. 0%; Anesthesia & Analgesia, 3.4% vs. 0.3%; totally, 6.4% vs. 0.4%). A significant increasing trend in annual proportion of articles with ECA was found in the three journals. The first two authors listed in the byline had equal credit in most cases.

Conclusions/Significance

The practice of giving authors equal credit in original research papers is increasingly common in major anaesthesia journals. It may be warranted for the journals to guide the authors how to regard this practice.  相似文献   

18.
本文结合作者参加医学实验动物专业英语教学和在美国访问学习经历,介绍了几种在专业英语教学中强化学生综合运用语言能力的方法,希望能够起到抛砖引玉的作用,为促进学生掌握该专业英语语言特点,提高学习效率和实际应用能力提供有益的参考。  相似文献   

19.
The authors report three cases of a new syndrome which characteristic anomalies are facial dysmorphism with anteverted nose, down slanting palpebral fissures, ptosis, severe microretrognatia, polydactyly. The authors insist on the particular severe genital anomalies, the failure to thrive and the constant lethal issue. The authors discuss the diagnosis of Smith-Lemli-Opitz syndrome and suggest the possibility of a new entity always confounded with others associations characterized by a polydactyly and a sexual reversion in male.  相似文献   

20.
The ability to interpret and reason from Tree of Life diagrams is a key component of twenty-first century science literacy. This article reports on the authors’ continued development of a multifaceted research-based curriculum – including an instructional booklet, lectures, laboratories and a field activity – to teach such tree thinking to biology students. Results are presented from a study involving biology students enrolled in an upper level organismal biology class. All students received the multi-week tree-thinking curriculum, and learning was assessed by comparing pretest and posttest scores on the novel tree-thinking assessment instrument developed by the authors. Quantitatively, the authors found large gains in tree-thinking abilities due to their instruction. The results also provided qualitative evidence that the authors succeeded in their more general goal of helping students to appreciate the interconnectedness of Earth’s biodiversity through the utility of phylogenetic trees.  相似文献   

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