中国纳入一级保护的极小种群野生植物濒危机制

为科学有效地保护极小种群野生植物, 明确其濒危机制具有重要意义。本文通过分析中国28种极小种群一级保护野生植物的种群特征及其濒危的内在原因和受威胁因素等, 总结了极小种群野生植物的濒危机制。极小种群野生植物的种群特征表现为遗传多样性低(13种)、衰退型种群结构(11种)、聚集型分布(11种)且分布区域狭窄(20种)。极小种群野生植物濒危的内在原因主要是繁殖力低(21种)和竞争能力弱(16种)。受威胁因素主要包括过度采挖等人类活动导致的种群数量减少(15种)和生境破坏(25种)以及气候变化等。因此, 除了保护极小种群野生植物免遭人类活动破坏, 保护策略应加强关注种群规模的维持和遗传多样性的保护。     

野生朱鹮种群扩散及其保护研究调查分析

通过对野生朱鹮种群的自然扩散及人工扩散数量的变化和朱鹮保护措施的调查,取得比较完整的关于野生朱鹮种群扩散和保护措施资料,可以为进一步拓展研究野生朱鹮种群扩散和保护措施提供理论数据和实证资料奠定基础。     

极小种群野生植物坡垒的研究现状和展望

极小种群野生植物因其分布范围狭窄且个体数量稀少,加之解濒技术不完善等随时面临灭绝风险,亟需进行拯救性保护。由于各极小种群野生植物自身生物学特性和致濒机理存在差异,针对特定物种开展基础性研究有助于为其保护和种群复壮提供科学依据。坡垒(Hopea hainanensis)曾是海南热带雨林的关键树种和表征种,但在人类活动和更新困难等因素的影响下,该极小种群野生植物的种群数量急剧减少。尽管已开展了较多研究工作,但资源现状不明、机理性研究缺乏、未来研究重点不清和科研未能有效指导保育实践等问题仍十分突出,长期性、深入性和系统性研究亟待加强。该文在全面检索相关文献的基础上,从生物学特性、自然分布区域、野生种群数量、适应性、就地和迁地保护、人工繁育技术和潜在濒危机制等方面系统回顾了坡垒的研究进展,讨论了极小种群野生植物保育工作中存在的问题和未来的研究重点,并基于目前的研究现状提出具体建议,以期为坡垒的保护和拯救提供参考。     

中国极小种群野生植物的保护现状评估

广阔的地域和多样的地形造就了中国丰富的生物多样性, 同时长时间的人类活动也导致我国有不少物种的生存受到威胁, 特别是一些极度濒危、随时有灭绝危险、生境要求独特、生态幅狭窄或基因易流失的物种需要重点保护。近期国家出台了《全国野生动植物及自然保护区建设工程总体规划》, 其中包含了首批重点保护的极小种群植物名单。本研究中, 我们整理了120种极小种群野生植物的高精度分布图, 探讨其分布格局并通过国家级和省级保护区网络评估其保护现状。研究发现, 中国极小种群野生植物丰富度最高的地方是云南东南部、广西西南部和海南岛西南部。国家级自然保护区对中国极小种群野生植物分布区的平均覆盖率为21.5%, 省级自然保护区的平均覆盖率为10.9%。有35种极小种群野生植物(占总数的29%)未受国家级自然保护区覆盖, 有17种(14%)未受任何国家级或省级自然保护区覆盖。我们建议在云南和海南省针对极小种群建立自然保护区。     

极小种群野生植物的近地保护

低于最小存活种群（Minimum Viable Population,简称：MVP）界线而濒临灭绝的极小种群野生植物是需要最优先保护的物种。“近地保护”是云南省林业厅在近年提出的对极小种群野生植物进行保护的一种新方法,它已成为国家林业局的野生植物六大拯救措施之一。根据近年来云南省对极小种群野生植物近地保护的实践和所取得的成果,以及经笔者对若干种国家重点保护植物在迁地保护与就地保护条件下的生长与适应性的比较研究,认为对包括极小种群在内的受严重威胁植物的近地保护的有效性远高于对它们的迁地保护。因而,笔者建议,应该尽快建立和完善野生植物近地保护体系,进一步加强极小种群野生植物高风险灭绝机制的研究,才能有的放矢地选择恰当的保护方法和科学的措施,以及在近地保护的实践中还必须遵循气候相似、生境相似和群落相似的生态学原则,以减少投入和提高其保护的有效性。     

极小种群植物白果蒲桃种群现状与保护评价

白果蒲桃是福建省云霄县特有极小种群植物,对其进行种群现状研究和保护评价。结果表明:现存白果蒲桃种群只有25株,母树仅1株,除母树和1株小树外,其余均为幼苗幼树,数量稀少,缺乏中树、大树等龄级阶段。幼苗幼树空间分布不均匀,绝大多数分布于距离母树10～25 m的范围内。种群龄级结构不连续,种群发展呈不可持续状态。种群竞争主要来自其他伴生树种,其中,厚壳桂竞争指数占总竞争指数的66.6%,远高于其他种类。本研究构建珍稀濒危暨极小种群植物保护综合评价指标体系,从濒危程度、保护价值和保护优先性3个方面对白果蒲桃进行保护评价。白果蒲桃濒危程度为Ⅰ级(濒危程度指数为4.510),属于极危种,保护价值为Ⅰ级(保护价值指数为4.052),保护价值极大,保护优先性为Ⅰ级(保护优先性指数为4.016),应列为最优先保护级别。     

极小种群濒危植物盐桦迁地保护研究

盐桦(Betula halophila Ching ex P.C.Li)是我国120个极小种群野生植物之一,仅分布于我国新疆阿勒泰地区.为了解其在迁地保护过程中对环境的适应性和沿海强风环境等对幼苗生长的影响,以山东烟台迁地保护基地内两个盐桦居群为材料,对其3年的生长量、果实性状、叶性状以及叶片生态化学计量等进行研究,利...     

极小种群濒危植物盐桦迁地保护研究

盐桦（Betula halophila Ching ex P.C.Li）是我国120个极小种群野生植物之一,仅分布于我国新疆阿勒泰地区。为了解其在迁地保护过程中对环境的适应性和沿海强风环境等对幼苗生长的影响,以山东烟台迁地保护基地内两个盐桦居群为材料,对其3年的生长量、果实性状、叶性状以及叶片生态化学计量等进行研究,利用独立样本t检验和贝叶斯方差分析对山东迁地保护两个居群和新疆迁地保护居群进行比较分析。结果显示,经过3年的生长,盐桦在烟台地区适应性良好,能在一个生长周期结出果实,设置风障以后盐桦生长速度显著升高,表明在幼苗敏感期设置风障可以为幼苗越冬提供保障,同时风障营造的相对稳定的环境提高了盐桦对资源环境的利用能力。     

中国极小种群野生植物保护理论与实践研究进展

极小种群野生植物大都分布范围狭窄、个体数量稀少且自然更新困难, 面临随时灭绝的风险, 迫切需要拯救性保护。极小种群野生植物这一概念自提出以来受到了保护生物学领域的广泛关注, 已成为当前中国生物多样性保护的一个热点方向。我国于2010年正式启动实施极小种群野生植物拯救保护工程, 并开展了大量的保护研究和实践。以“extremely small population*”和“plant”为检索词在Web of Science进行了主题检索, 以“极小种群”和“植物”为检索词在中国知网进行了主题检索, 对获取的的学术期刊论文、学位论文和会议论文进行了梳理。本文从极小种群野生植物种群、群落及生境调查与监测、适应性、遗传多样性、繁殖生物学、濒危机制、动态模型6个方面对近年来极小种群野生植物的理论研究工作进行了较为系统的综述。在此基础上, 从就地保护、迁地保护与种质资源保存、野外回归、人工繁育、标准化体系5个方面回顾了极小种群野生植物保护实践及取得的进展。基于极小种群野生植物保护理论与实践研究现状, 我们建议在极小种群野生植物未来保护工作中不断调整和完善保护名录, 加强种群结构的观测和预测、小种群形成和恢复机制的针对性研究以及特定物种的长期系统性研究, 同时促进这一概念在国际上的推广。希望本文能为国家生物多样性保护和生态文明建设提供参考。     

典型极小种群野生植物保护与恢复技术研究

极小种群野生植物是急需优先抢救的国家重点保护濒危植物。目前,有关极小种群野生植物濒危原因及相应解濒技术的研究还非常缺乏,已有的植物种群生态学和保护生物学理论对极小种群植物并不完全适用,迫切需要研发有针对性的科学理论和保育技术。介绍了国家重点研发计划项目\"典型极小种群野生植物保护与恢复技术研究(2016YFC0503100)\"的研究意义、内容、目标及展望。项目拟针对典型极小种群野生植物开展保护与恢复技术的研究,拟构建极小种群野生植物的种群生态学和保护生物学理论体系,研发极小种群野生植物保护和更新复壮的技术体系,并建立相应的应用技术标准和示范基地,为极小种群野生植物的保护与可持续利用奠定坚实的理论基础和技术支撑。     

朱■（Nipponianippon）种群生存力分析

到目前为止,只有一个野生朱群体幸存下来,而且它的种群大小自１９８１年重新发现以来,一直在２０只以下波动。本文应用种群生存力分析的方法,借助漩涡模型,根据朱１４年的种群数据,总结和预测了其种群动态,并着重研究了朱的濒危程度。结果显示,按过去１０余年的生存状况,朱在５０年内绝灭的可能性是９８．５％,平均绝灭时间为１５．７２年。现存种群数量很低,所以种群统计随机性对其命运有很大影响。灵敏度分析表明,当前的朱种群对意外死亡和生存环境的波动较为敏感。保护工作的优先项目是对猎杀和天敌的控制以及从各个方面提高朱的生活质量     

中国朱鹮DNA多态性研究进展

朱鹮是我国四大国宝之一,世界极濒危级鸟类。朱鹮的遗传多样性保护研究将成为生物多样性保护研究中的热点。本文主要介绍了朱在蛋白质多态、随机扩增多态DNA、微卫星多态性、随机扩增微卫星多态性和线粒体DNA序列多态性方面的研究结果,表明中国朱群体遗传多态性的贫乏,并据此阐述了DNA多态性保护的相关对策。     

Major Histocompatibility Complex Variation in the Endangered Crested Ibis Nipponia nippon and Implications for Reintroduction

The major histocompatibility complex (MHC), with its extraordinary levels of genetic variation, is thought to be an essential aspect of the ability of an organism to recognize different parasites and pathogens. It has also been proposed to regulate reproductive processes in many aspects. Here we examine the genetic variation of the second exon of the MHC class II B genes of the crested ibis, an endangered species known to descend from just two breeding pairs rediscovered in 1981. Only five alleles are identified by single-strand conformation polymorphism (SSCP) analysis of 36 samples taken from both wild and captive populations, and a comparatively low level of divergence between MHC alleles is observed. We suggest that representative sampling of individuals with most of the different MHC allele genotypes to constitute a founder population, together with the monitoring of the pathogen status of candidate sites before release, is of great importance for raising the success rate of reintroduction for the crested ibis.     

朱鹮野化种群对冬季低温的行为响应

低温对鸟类的生长发育、新陈代谢和生活状态有显著的影响,鸟类往往通过改变行为模式来适应温度的变化。朱鹮(Nipponia nippon)是东亚特有的濒危鸟类,2018年从秦岭南麓的陕西洋县引入到河北北戴河,建立了全球纬度最高的野化种群。本文以北戴河和洋县两个野化种群为研究对象,采用瞬时扫描法观察分析了季节和温度等因素对朱鹮休息行为的影响。结果表明,双腿站立露喙是朱鹮在游荡期最常见的休息行为(70.9%),但在越冬期显著降低(55.6%),而单腿站立和隐喙行为比例相应升高。温度对双腿站立隐喙、单腿站立露喙和单腿站立隐喙3种行为的比例有显著影响。可见,朱鹮在冬季通过增加保护裸露部位的行为比例来适应低温。在冬季,随着温度的下降,朱鹮趴卧在树干上的夜宿行为比例逐渐增加,而这一行为在白天没有记录到。温度对成鸟和幼鸟冬季的休息行为有显著影响。由此表明,趴卧行为很可能是朱鹮对极端耐受低温的一种应对,在保护监测过程中需警惕。朱鹮在北戴河越冬过程中没有使用网笼中的遮挡伞棚和庇护场所,表明其能够自主适应-20℃的低温。为了确保野化朱鹮顺利越冬,建议在野化网笼中增加一些松科等常绿树种,为朱鹮提供更加优良的夜宿环境,并用稻草搭建风挡,减少夜间大风的负面影响。     

Unintentional parasite conservation success: chewing lice recovered from Crested Ibis,Nipponia nippon,in breeding program facilities in Shaanxi,China

The crested ibis has survived a dramatic population decline during the twentieth century, declining from a range across much of China, Japan, the Korean peninsula and nearby Russia, to a known world population of seven individuals. These formed the basis of a successful breeding program in Shaanxi, China. We examined ibises in this breeding program for ectoparasites, to establish whether any of the three chewing louse species known from this host had survived this severe host population bottleneck. We recovered representatives of three species of lice, identified as the same species as those previously known from the wild populations: Ardeicola nippon, Colpocephalum nipponi, and Ibidoecus meinertzhageni. Of these, the two first species were recovered from almost all examined hosts, whereas I. meinertzhageni was more rare. As these lice are host specific, this implies that all three louse species remarkably survived this bottleneck, and are now thriving in both the reintroduced and captive populations of crested ibis. This constitutes an unintentional success story in the conservation of parasitic species. We provide the first photos of all three species, as well as a preliminary assessment of their conservation status, and discuss the future of chewing louse conservation.

     

Reduced Dependence of Crested Ibis on Winter-Flooded Rice Fields: Implications for Their Conservation

The Crested Ibis Nipponia nippon was once thought to be extinct in the wild until seven birds were discovered in a remote mountain village in China in 1981. Studies suggested that winter-flooded rice fields play an essential role in nest site selection by the Crested Ibis and hence in their survival. Considerable efforts were therefore made to conserve the winter-flooded rice fields, but these have caused conflicts between the agricultural and conservation communities. The population and geographical range of the wild Crested Ibis has expanded greatly since 1981, but there is no spatial information on the winter-flooded rice fields, nor on the current association of nest sites and winter-flooded rice fields. We mapped winter-flooded rice fields across the entire current range of Crested Ibis using innovative remote sensing and geographical information systems (GIS) techniques. The spatial relationships between the nest site clusters and winter-flooded rice fields were quantified using Ward''s hierarchical clustering method and Ripley''s K-function. We show that both have significantly clumped distribution patterns and that they are positively associated. However, the dependence of Crested Ibis on the winter-flooded rice fields varied significantly among the nest site clusters and has decreased over the years, indicating the absence of winter-flooded rice fields is not constraining their recovery and population expansion. We therefore recommend that efforts should be made to protect the existing winter-flooded rice fields and to restore the functionality of natural and semi-natural wetlands, to encourage both in-situ conservation and the re-introduction of the Crested Ibis. In addition, we recommend that caution should be exercised when interpreting the habitat requirements of species with a narrow distribution, particularly when that interpretation is based only on their current habitat.     

Special Issue for Plant Species with Extremely Small Populations(PSESP):Call for papers

正Plant species with extremely small populations(PSESP)refers to plants with unique topography and habitat,extremely limited distribution range,enormous pressure due to habitat destruction and habitat in plant diversity hotspots with poor economic development.PSESP,a new conservation action concept first promulgated in Yunnan Province,is becoming more widely accepted in China.Several national and regional conservation strategies and actions for conser-     

Molecular Cloning and Biochemical Analysis of Tyrosinase from the Crested Ibis in China

The crested ibis, one of the most endangered birds in the world, could benefit from research into its genetic diversity as a tool for conservation in the future. Tyrosinase is thought to play a major role in the production of common yellow to black melanins in birds. We have cloned and sequenced four exons of the crested ibis tyrosinase gene and discovered that the amino acid sequence has high similarity to zebra finch tyrosinase (93?%), followed by chicken (91?%) and quail (91?%). Some functional and structural domains in the crested ibis tyrosinase coding area were found to be conserved during evolution. Nine sequence variants were found in the partial coding sequence, one in exon 1 and eight in exon 4. Sequence variant 1 (SV1) shows intermediate polymorphism (0.25?<?PIC?<?0.5), and further study is needed to determine whether it can be used as a potential molecular marker in crested ibis artificial breeding programs.