试论植物园功能变迁与中国国家植物园体系建设

植物资源是自然生态系统的基本组成部分, 是经济社会可持续发展的重要物质来源, 植物多样性是关系到国家生态安全和生物安全的战略资源。就地保护和迁地保护是植物多样性保护的两种主要方法, 构建以国家公园为主体的自然保护地体系是就地保护的主要形式, 构建以国家植物园为引领的植物园体系是迁地保护的主要形式, 二者相辅相成, 共同形成我国较为完整的植物多样性保护体系。通过建设国家植物园体系对我国植物多样性进行迁地保护, 同时开展科学研究、园林展示、科普教育和资源开发利用, 对深入推进生态文明建设和高质量发展具有重要意义。本文回顾了植物园的功能变迁、全球和中国植物园分布与数量以及植物迁地保护现状,讨论了植物园与植物迁地保护的关系, 在此基础上, 提出了我国国家植物园的定义及设立标准, 进而讨论了建设国家植物园体系的意义、挑战、统筹迁地保护和就地保护等问题, 最后提出了我国国家植物园体系的建设目标、管理体制、空间布局和认证等方面的建议, 以期为我国的国家植物园体系建设提供参考。     

植物园与植物回归

为了有效保护珍稀濒危植物,植物园在迁地保护过程中开始关注迁地保护和野外回归相结合,其拥有的活植物资源、知识、技能和设施可为植物回归提供重要支撑。早期的植物回归实践注重用园艺手段增加种苗存活率,后来强调了种群恢复,并把植物回归放到生态系统恢复的背景下考虑,近几年则强调了全球变化背景下的植物回归。目前,全世界植物园的回归研究和实践进展主要集中在影响回归植株定居的因素、回归的遗传多样性、全球变化对回归的影响和成功回归的标准等四方面。在人类干扰和全球变化情景下,植物园需要综合考虑就地保护、迁地保护和回归三位一体的综合保育体系,以实现植物多样性的有效保护。     

明党参的濒危机制及其保护对策的研究

本文对明党参的资源状况、种群生态、种子结构、植株结构实率与环境的关系及传粉生物学等方面进行了研究。从种子形态及分子水平对明党参的遗传多样性和遗传结构进行了分析。研究结果表明,明党参种子后熟阶段与梅雨气候的不协调是导致种子萌发率低及更新种群少的主要原因之一;人类活动破坏了明党参的适宜生境和种群数量,使得种群间基因流减小,进而导致严重的遗传漂变及种群间的分化。由此提出了对明常参就地和迁地保护的有效措施。     

中国植物引种栽培及迁地保护的现状与展望

本文在概要总结我国植物引种驯化和迁地保育的历史基础上,全面综述了中国植物园迁地保育植物的现状和特点、中国农作物种质资源保护现状、野生植物种子库的进展。我国植物园迁地栽培植物约396个科、3,633个属、23,340个种;我国农作物资源保存数量达到41.2万份,涉及作物种及近缘种1,890个;我国野生生物种质资源库收集植物种子5.4万份、7,271种植物。文章同时阐述了我国植物迁地保护存在的问题并对相关领域的未来发展进行了展望:(1)启动《中国迁地栽培植物志》编研计划;(2)部署迁地保护与就地保护的整合研究;(3)加强我国特有植物类群的迁地保育原理和方法研究;(4)促进基于迁地保育濒危植物的野外回归:(5)拓展重要植物资源的评价及发掘利用。     

中国履行《生物多样性公约》二十年: 行动、进展与展望

1992年6月联合国环境与发展大会(UNCED)通过了具有里程碑意义的《生物多样性公约》, 至今已经20年。在此期间, 中国1993年建立了履行《公约》的国家协调机制, 1995-1997年实施了“中国生物多样性国情研究”, 2007-2010年编制了《中国生物多样性保护国家战略与行动计划》, 2011年建立了“中国生物多样性保护国家委员会”, 并针对《生物多样性公约》的目标, 实施了多项生物多样性研究和保护行动, 包括森林、草原、荒漠、湿地、海洋等自然生态系统保护; 物种资源调查、编目、数据库建设以及珍稀濒危物种保护; 外来入侵种防治与转基因生物生态风险评估等。同时, 在生物多样性本底查明、监测体系建立、就地保护、遗传资源获取与惠益分享、传统知识的保护与应用等方面还存在很多挑战, 为此, 本文有针对性地提出了区域生物多样性本底查明、就地保护和遗传资源及相关传统知识获取与惠益分享等未来重点研究方向。     

奠基者效应对海南坡鹿迁地保护种群遗传多样性的影响

在迁地保护中,奠基者效应通常会导致新建种群与源种群的遗传分化,并使新建种群的遗传多样性低于源种群。海南坡鹿(Cervuseldi hainanus)是世界濒危种,野生种群仅分布在中国海南岛。由于栖息地破坏和过度狩猎,至20世纪70年代,这个物种仅剩26只,已经濒临绝灭,被列为国家一级保护动物。自1976年开始对海南坡鹿实施就地保护和迁地保护,该种群的数量从最初的26只增加到1600多只。本文采用10个微卫星位点对一个源种群(大田种群)和5个迁地种群(邦溪、甘什岭、枫木、金牛岭、文昌种群)的遗传多样性进行检测,结果发现6个种群的遗传多样性水平均较低(He≈0·3);5个迁地种群分别有1、3或5个单态位点,大田种群无单态位点;邦溪种群与大田种群遗传分化显著,而甘什岭种群与大田种群的遗传分化不显著。结果表明,奠基者效应导致种群的遗传多样性水平较低,并且对于不同迁地种群,影响也不相同。造成这些差异的因素有建群者数量、引种方式和建群种群的结构。该研究为今后在海南岛建立新的海南坡鹿迁地种群提供建议和参考,同时也为其他濒危物种的迁地保护提供理论指导。     

保护区依靠当地人民,最重要的是依靠他们的传统知识——裴盛基谈两个多样性(五)

生物多样性保护的主要方法是就地保护、迁地保护和种质保存。"就地保护"是公认的最好保护方法,不仅保护物种而且保护了栖息地。建立自然保护区是就地保护的有效形式。这要从两方面说起,第一,政府立法建立自然保护区,只是一种行政手段,因为生物多样性受到前所未有的威胁,社会经济发展如此之     

南方红豆杉迁地保护小种群适应性进化机制研究

为了解南方红豆杉迁地保护种群的适应性进化机制,以南京中山植物园内南方红豆杉迁地保护栽培种群和扩散的衍生种群为材料,以引种初始地江西野生种群为对照,对南方红豆杉群落的结构、遗传多样性及遗传结构进行分析和研究。结果表明,南方红豆杉野生种群和迁地保护种群均维持着较高水平的遗传多样性,其中野生种群遗传多样性稍高于迁地保护小种群,但迁地保护种群中南方红豆杉个体密度大于野生种群。同时,种群内的遗传变异所占比例大于种群间的。整体来看,南方红豆杉迁地保护种群还处于演替早期,存在不明显的奠基者效应,有进一步演替发展的可能。     

广东兰科植物多样性保育现状

为了使广东省的兰科植物及其遗传多样性得到有效的保育, 保存我国重要野生植物资源, 在2017-2019年间, 采用样线和样地相结合的调查手段、专家快速评估和野外调查相结合的评估技术以及Wilcoxon符号秩检验和Friedman检验的统计方法, 对广东省自然分布的兰科植物进行了全面的调查和濒危等级评估, 并对其在广东省自然保护区中的就地保育情况和全国植物园中的迁地保育情况进行了综合分析。结果表明, 广东省分布有兰科植物80属235种, 其中广东特有种20种; 广东兰科植物受威胁物种有186种, 其中极危11种、濒危114种、易危61种; 就地保育的兰科植物有111种, 迁地保育的兰科植物有156种, 就地和迁地共同保育的兰科植物有96种, 保育的有效程度较低; 另外, 就地、迁地、就地和迁地共同保育的兰科植物之间没有体现出明显的差异, 保育工作缺乏选择性和针对性。基于此, 我们建议广东兰科植物的保育工作应重视基础数据的收集和持续的野外监测、提高保育物种的数量、优化迁地保育物种的选择性和针对性、完善迁地保育和就地保育之间的协同性, 同时也应重视立法和公众教育, 并构建广东兰科植物保育的网络系统。     

迁地保护应当具有明确的灵活性

早期的新闻报道中提到国家植物园体系“逐步实现中国85%以上野生本土植物、全部重点保护野生植物种类得到迁地保护”的建设目标引发了质疑。实际上,《中国植物园体系布局方案》明确了更为实际的目标,包括到2025年设立5个左右国家植物园,实现70%以上的国家重点保护野生植物得到迁地保护;到2035年设立10个左右国家植物园,实现80%以上的国家重点保护野生植物得到有效迁地保护。植物园体系应当建立明确的迁地保护分级标准,即使在迁地栽培无法达到最高级别的保护标准时,仍可视为某种较低级别的迁地保护。迁地保护工作应与中国植物园体系有机结合,包括国家植物园、地区优秀植物园和地方植物园。通过全国植物引种数据联网共享的可能性,区域性和基层植物园可参与到迁地保护工作中,共同承担任务份额。迁地保护与就地保护、引种驯化并非对立的关系。就地保护优于迁地保护,但二者是相辅相成的关系。迁地保护和引种驯化并非绝对对立,可实现既保护又开发的目标。总体而言,未来迁地保护工作的一个重要方向是建立清晰的分级标准和数据网络,以明确迁地保护与其他保护形式的关系,实现明确的灵活性。     

天鹅洲迁地保护江豚群体的遗传评估与发展预测

文章以2008年春季遭受严重雪灾的天鹅洲白鱀豚国家级自然保护区迁地保护江豚群体为研究对象,利用物种特异性微卫星遗传标记对该群体的遗传多样性进行了评估,并通过软件对其发展趋势进行了模拟和预测。研究结果表明,虽然2008年春季雪灾并未导致该群体遗传多样性的严重损失,灾后群体依然表现出中等水平的微卫星遗传多样性(18个座位的平均等位基因数为4.780,平均观察杂合度和期望杂合度分别为0.748和0.674);但模拟结果显示,该迁地保护江豚群体的遗传多样性将快速下降,100年后仅能保留约79%的等位基因和约84%的遗传杂合度。此外,模拟结果表明,通过增加群体数量和调整群体性比可有效减缓该群体遗传多样性的下降速度。根据研究结果,并结合长江江豚自然种群快速下降的现状,作者提出天鹅洲迁地保护江豚群体当前最重要的保护策略应该是尽早补充一定数量的、合适的野生个体,在加强遗传多样性保护的同时使其群体数量快速增长并形成一个更大规模的有效繁殖群体。     

注意植物迁地保护中的遗传风险

稀有濒危植物迁地保护的长期目标之一就是要保护物种的遗传多样性和进化潜力。介绍了稀有濒危植物在植物园迁地保护过程中存在的一系列遗传风险。由于引种或取样的不足,容易导致被保存的物种缺乏足够的遗传代表性;盲目的引种、不合理的定植以及材料的来源不清则会导致稀有濒危植物的遗传混杂、近交衰退或杂交衰退;人为选择和生长环境的改变也容易造成濒危物种对迁地保护的遗传适应。在实际的迁地保护工作中,这些遗传风险往往被忽视。植物迁地保护中遗传风险将严重影响稀有濒危物种的回归和恢复。植物园应当重视濒危植物的遗传管理,以降低或避免迁地保护中的遗传风险。Abstract: Conserving genetic diversity of rare and endangered species and their evolutionary potential is one of the long-term goals of ex-situ conservation. Some potential genetic risks in ex-situ conservation in botanical gardens are presented. The preserved species may lack genetic representativity because of poor sampling. Inappropriate plantations, inadequate records and unclear kinships jeopardize endangered species to genetic confusion, inbreeding depression or outbreeding depression. Artificial selection and habitat conversion also potentially result endangered plants in adapting to ex-situ conservation, which had been usually overlooked. All the genetic risks can decrease the success of reintroduction and recovery. Therefore, appropriate genetic management should be carried out in botanical gardens to decrease or avoid genetic risks in ex-situ conservation.     

巴西植物遗传资源保护与对外交流管理

巴西拥有高等植物55000种,居世界第一。植被分为6个区系,即亚马逊雨林、塞拉多(Cerrado)稀树草原、卡廷加(Caatinga)旱生植被、大西洋雨林、南方森林草原和潘塔纳尔(Pantanal)湿地植被。已建立554个原生境保护区和126个基因库,保存植物遗传资源25万份。对外交流由巴西农业科学院(EMBRAPA)遗传资源与生物技术中心(CENARGEN)统一管理。     

Capturing,protecting and restoring plant diversity in the UK: RBG Kew and the Millennium Seed Bank

Ex situ seed banking is a practical and cost-effective means of preserving wild plant diversity and a crucial complement to the in situ conservation and restoration of species and habitats. As pressures on the natural environment have grown, so has the call for seed banks to provide scientifically-robust,practical solutions to seed-related problems in nature conservation, from single-species recovery and reintroduction to the restoration of complex, dynamic communities at the largest scales. In this paper, we discuss how the Royal Botanic Gardens, Kew and its Millennium Seed Bank have responded to this call in the United Kingdom. We demonstrate that banked seed collections can provide a range of otherwiseunavailable, high quality, known-origin, genetically-diverse biological materials. The data, expertise and specialist facilities that accompany these collections are also valuable, helping overcome constraints to the collection, production and effective use of native seed. Challenges remain-to ensure ex situ collections protect the species and genetic diversity that will enable plants to adapt to a changing environment, and to find new ways for seed banks to mobilise their resources at a landscape scale.     

Long‐distance pollen and seed dispersal and inbreeding depression in Hymenaea stigonocarpa (Fabaceae: Caesalpinioideae) in the Brazilian savannah

Hymenaea stigonocarpa is a neotropical tree that is economically important due to its high‐quality wood; however, because it has been exploited extensively, it is currently considered threatened. Microsatellite loci were used to investigate the pollen and seed dispersal, mating patterns, spatial genetic structure (SGS), genetic diversity, and inbreeding depression in H. stigonocarpa adults, juveniles, and open‐pollinated seeds, which were sampled from isolated trees in a pasture and trees within a forest fragment in the Brazilian savannah. We found that the species presented a mixed mating system, with population and individual variations in the outcrossing rate (0.53–1.0). The studied populations were not genetically isolated due to pollen and seed flow between the studied populations and between the populations and individuals located outside of the study area. Pollen and seed dispersal occurred over long distances (>8 km); however, the dispersal patterns were isolated by distance, with a high frequency of mating occurring between near‐neighbor trees and seeds dispersed near the parent trees. The correlated mating for individual seed trees was higher within than among fruits, indicating that fruits present a high proportion of full‐sibs. Genetic diversity and SGS were similar among the populations, but offspring showed evidence of inbreeding, mainly originating from mating among related trees, which suggests inbreeding depression between the seed and adult stages. Selfing resulted in a higher inbreeding depression than mating among relatives, as assessed through survival and height. As the populations are not genetically isolated, both are important targets for in situ conservation to maintain their genetic diversity; for ex situ conservation, seeds can be collected from at least 78 trees in both populations separated by at least 250 m.     

Morphological and phenological comparisons of two Hopi maize varieties conserved in situ and ex situ

Over the last twenty-five years, crop genetic resources (CGR) have been preserved in genebanks around the world for use by formal plant breeders. Recently conservation of folk crop varieties for direct use by the farmer-breeders of traditional agricultural communities has been suggested as another purpose for CGR conservation. While both in and ex situ CGR conservation programs have been proposed to meet the needs of formal plant breeders and farming communities, the needs and goals of the two groups are different. Formal breeders seek maximum allelic diversity while farmer-breeders are interested in both diversity and population structure that provide local adaptation. Based on the morphological and phenological data analyzed for this study of two Hopi maize varieties conserved in and ex situ, it appears that both genetic shift and genetic drift have occurred ex situ, and that populations conserved ex situ are different from those maintained in situ. These findings suggest that CGR conservation strategies must be re-evaluated in light of the specific conservation goals that are sought.     

Isozymes and DNA markers in gene conservation of forest trees

For long-lived plants that have to cope with high temporal and spatial environmental heterogeneity, genetic diversity is of prime importance for species persistence. Detrimental anthropogenic impact on the gene pool of forest trees calls for conservation of genetic resources. Potentials and limitations of isozymes and DNA markers in forest genetic conservation are reviewed. These markers can contribute to conservation with respect to the delimitations of species and hybrid zones, as well as the assessment of genetic diversity within and among populations. Markers are valuable to identify resource populations, since today‘s genetic diversity in forest trees is predominantly the result of plant history (e.g. glacial refuges, migration). Several suggestions have been put forward to optimize sampling of in situ or ex situ populations on the grounds of marker data. Restraint in this area is recommended. Different types of genetic markers (terpenes, isozymes, nuclear and extrachromosomal DNA polymorphisms) and quantitative traits yield different information about genetic diversity and population differentiation. Hence identification of resource populations should not solely be based upon a certain marker type or on quantitative traits alone. The capability of available markers to predict or assess adaptive potentials in forest tree populations is still very limited. This revised version was published online in August 2006 with corrections to the Cover Date.     

An early evaluation of translocation actions for endangered plant species on Mediterranean islands

In situ conservation is widely considered a primary conservation strategy. Plant translocation, specifically, represents an important tool for reducing the extinction risk of threatened species. However, thus far, few documented translocations have been carried out in the Mediterranean islands. The CareMediflora project, carried out on six Mediterranean islands, tackles both short-and long-term needs for the insular endangered plants through in situ and ex situ conservation actions. The project approach is based on using ex situ activities as a tool to improve in situ conservation of threatened plant species.Fifty island plants(representing 45 taxa) were selected for translocations using common criteria.During the translocations, several approaches were used, which differed in site selection method, origin of genetic material, type of propagative material, planting method, and more. Although only preliminary data are available, some general lessons can be learned from the experience of the CareMediflora project. Among the factors restricting the implementation of translocations, limited financial resources appear to be the most important. Specific preliminary management actions, sometimes to be reiterated after translocation, increase the overall cost, but often are necessary for translocation success. Translocation using juvenile/reproductive plants produces better results over the short term,although seeds may provide good results over the long run(to be assessed in the future). Regardless,plant translocation success can only be detected over long periods; therefore, proper evaluation of plant translocations requires a long-term monitoring protocol. Care-Mediflora project represents the first attempt to combine the existing approaches in a common plant conservation strategy specifically focusing on the Mediterranean islands.     

试论野生稻资源遗传多样性原生境保存

我国野生稻资源丰富,分布地域广阔,由于经济建设用地需要,近年来野生稻原生地遭到严重破坏,野生稻原生境保存已是十分紧迫的事情。本文论述了原生境保存的意义,原生境保存地的选择原则及设想,旨在提高全民生态保护意识,加强野生稻资源保护。     

种质资源保存的战略问题和面临的挑战

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