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1.
Tulipa cypria, a Cyprus endemic plant, is protected under local and international legislations and categorised as “Endangered” by IUCN. Detailed habitat and distribution information was previously limited, particularly for northern Cyprus. Our objective was to accurately map the distribution and to collect habitat, subpopulation and threat data to enable a conservation status reassessment at global and regional levels. We gathered all available data and conducted extensive surveys focusing on northern Cyprus in 2014–2015, identifying 17 extant subpopulations amounting to 7765 individuals and the loss of 2 historical subpopulations amounting to 3500 individuals. We infer a continuous decline in population size and identify the major cause to be habitat loss through agriculture, with 75% of global habitats and 100% of northern Cyprus habitats being affected by it. We update the global assessment to Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v) and suggest regional assessments for northern Cyprus (Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v)), UN Buffer Zone (Endangered D1) and southern Cyprus (Endangered B2ab(iii)). Conservation priorities identified include initiation of gene transfer and life history studies, population trend monitoring and exsitu conservation actions.  相似文献   

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In this study, 12 microsatellite markers were developed from two microsatellite-enriched libraries (AG, AC) of Aconitum brachypodum, which were constructed using a FIASCO method. Polymorphism of each locus was assessed in 24 individuals of A. brachypodum. Number of alleles per locus (NA) ranged from 2 to 4. The average allele number of the microsatellites was 2.58 per locus. The observed (HO) and expected (HE) heterozygosities ranged from 0.125 to 0.875 and 0.117 to 0.612, respectively. Polymorphic information content (PIC) ranged from 0.110 to 0.531. Among the 12 microsatellite markers, three deviated from Hardy–Weinberg equilibrium significantly. These markers will facilitate further studies on the population genetics of A. brachypodum.  相似文献   

3.
江苏珍稀濒危植物的多样性、分布及保护   总被引:1,自引:0,他引:1  
掌握重点保护野生植物的濒危现状及评估濒危等级是制定科学保护策略的关键。根据江苏第二次重点保护野生植物资源调查(2012-2018)以及近年来相关调查资料, 我们采用世界自然保护联盟(IUCN)物种红色名录的濒危等级与评估标准, 对江苏分布的珍稀濒危植物的现状与濒危等级进行了评估与分析。结果表明: (1)江苏41种国家重点保护和濒危野生植物的濒危等级可以分为7个等级。包括地区灭绝(RE) 2种, 占总种数的4.88%; 极危(CR) 10种, 占24.39%; 濒危(EN) 6种, 占14.63%; 易危(VU) 13种, 占31.71%; 近危(NT) 2种, 占4.88%; 无危(LC) 2种, 占4.88%; 数据缺乏(DD) 6种, 占14.63%。其中, 受威胁物种(包括CR、EN和VU)有29种, 占总种数的70.73%。(2)建议的江苏重点保护野生植物有74种, 隶属于40科62属; 它们的受威胁比例较高, 达74.32%。江苏人口众多、环境资源压力较大, 近年来生产经营和土地利用方式的改变以及宣传教育不足很可能是导致这些原生物种濒危的主要原因。因此建议: (1)尽快制定江苏省级重点保护野生植物名录; (2)加强科学研究, 同时对部分濒危植物进行就地保护和迁地保护, 积极开展野外回归、近地保护和动态监测; (3)继续加大对重点保护野生植物的保护管理和宣传力度。  相似文献   

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Abstract Lilium lancifolium Thunb, is the only polyploid species complex consisting of 2x (2n=24) and 3x (2n=36) forms in the genus, both of which are highly self-sterile. They are cytologically differentiated into various nucleolar types by number and combination of four kinds of nucleolar chromosomes. The 3x form is widespread from the North-East district of China to the Japanese Islands through the Korean Peninsula. However, the 2x form is localized and grows singly or together with the 3x form in the narrow zone from southern Korea to the Tsushima Islands, Japan. The 2x form reproduces by sexual as well as by asexual means, but a sterile 3x form has asexually persisted to the present. Generally speaking, the 3x form is the allotriploid which has originated from hybridization between a 2x form and a closely related species such as L. maximowiczii in the remote past. In the present study, another possibility for the presence of the autotriploid form is newly proposed based on its karyotype and geographic distribution.  相似文献   

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截至2021年12月31日,中国已知苦苣苔科植物共有805种(含种下等级,下同),隶属于45个属,主要分布在我国西南至华南地区,其中特有种和狭域种十分丰富。由于苦苣苔科大部分种类仅适应于某些特化的微生境,因此极易因自身原因和外界因素的干扰而致危。为更好地了解中国苦苣苔科已知物种的濒危风险,该研究在查阅相关文献且结合最近发表的新分类群中关于濒危等级评估的相关内容,辅以近年来实地调查掌握的第一手资料,对中国苦苣苔科已知物种的濒危等级进行了统计分析和重新评估。同时,依托中国野生植物保护协会苦苣苔专业委员会、广西植物研究所国家苦苣苔科种质资源库和中国苦苣苔科植物保育中心平台,首次创新了从新种发现和发表到濒危状况评估、即时启动保育和园艺新品种培育同步进行的物种保护新模式。分析结果表明,有必要提高政府相关部门对苦苣苔科植物多样性保护的重视程度。因此,建议:(1)进一步加强对中国苦苣苔科植物种质资源保护紧迫性的认识;(2)针对濒危的尤其是被评估为极危(CR)和濒危(EN)的类群开展“抢救性”保护、迁地与就地保护和野外回归;(3)积极开展新品种培育等方面的研究。以上结果和建议是将来苦苣苔科植物多样性保...  相似文献   

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Reintroduction or translocation of threatened plant species, as part of in situ conservation efforts, often failed because of the lack or the poor quality of remaining natural habitats due to human disturbances and invasion by alien species, especially in island ecosystems. We conducted a study on Ochrosia tahitensis (Apocynaceae), a critically endangered endemic small tree in the tropical high volcanic island of Tahiti (French Polynesia, South Pacific) to find the most suitable sites for future translocation. Distribution models were produced based on climate, topography, and plant community inventories (i.e. species composition and abundance, canopy height and openness, basal area of woody species) of the few remnant populations. Results show that this species, comprising 32 reproductive trees within 16 populations known in the wild, remains restricted to a few ecological refuges representing a very small part of its potential ecological range located on the northwest side of the island, and shares its current habitats with a set of more common native woody species found in mesic-wet forests. The use of native plant communities as a proxy for habitat suitability along with species distribution modelling can enhance translocation success in island ecosystems, but only if the major threats causing population decrease, mainly forest destruction and fragmentation and invasive alien species, are effectively managed.  相似文献   

9.
Catfishes of the family Pangasiidae are an important group that contributes significantly to the fisheries of the Mekong River basin. In recent times the populations of several catfish species have declined, thought to be due to overfishing and habitat changes brought about by anthropogenic influences. The Mekong giant catfish Pangasianodon gigas Chevey, 1913 is listed as Critically Endangered on the IUCN Red List. In the present study, we assessed the level of genetic diversity of nine catfish species using sequences of the large subunit of mitochondrial DNA (16S rRNA). Approximately 570 base pairs (bp) were sequenced from 672 individuals of nine species. In all species studied, haplotype diversity and nucleotide diversity ranged from 0.118±0.101 to 0.667±0.141 and from 0.0002±0.0003 to 0.0016±0.0013, respectively. Four haplotypes were detected among 16 samples from natural populations of the critically endangered Mekong giant catfish. The results, in spite of the limited sample size for some species investigated, indicated that the level of genetic variation observed in wild populations of the Mekong giant catfish (haplotype diversity=0.350±0.148, nucleotide diversity=0.0009±0.0008) is commensurate with that of some other related species. This finding indicates that (1) wild populations of the Mekong giant catfish might be more robust than currently thought or (2) present wild populations of this species carry a genetic signature of the historically larger population(s). Findings from this study also have important implications for conservation of the Mekong giant catfish, especially in designing and implementing artificial breeding programme for restocking purposes.  相似文献   

10.
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   

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We report the identification of four residual stations for Trifolium michelianum Savi (Fabaceae) in Sicily, whereas the species was documented to be extinct at the Gorgo Cerro station (western Sicily), the only locality previously reported in the literature. In addition to an update on the distribution of the species, a survey on the new Sicilian populations led to their biological, ecological and phytosociological characterization, as well as to an assessment of the risk factors. The species, here relegated to the limit of its distribution area, occurs in particularly sensitive and vulnerable environments, such as the “Mediterranean temporary ponds”, considered “priority” by the Council Directive 92/43/EEC. Moreover, a new Sicilian association (Trifolio michelianiGlycerietumspicatae ass. nova), framed in the alliance Glycerio-Sparganion (class Phragmito-Magnocaricetea), is described.  相似文献   

13.
极小种群广东含笑野外资源现状   总被引:1,自引:0,他引:1  
为掌握极小种群广东含笑(Michelia guangdongensis)的种质资源现状并评估其濒危等级, 本文对广东含笑原生地——广东石门台国家级自然保护区及其邻近地区进行了系统的野外调查。结果表明: (1)目前发现广东含笑有4个野外分布区, 其中广东石门台国家级自然保护区红珠岩段和英德上天堂为首次报道。(2)船底顶是广东含笑最集中的分布区, 种群数量最多, 约有1,100株; 英德上天堂种群数量最少, 只有20株。(3)依据IUCN全球物种濒危等级评估标准, 广东含笑应当被评为濒危(EN, B1a + B2a)。  相似文献   

14.
Dendrobium wangliangii G. W. Hu, C. L. Long & X. H. Jin, a new species from the north of the Yunnan Province in China is described and illustrated. The morphological differences between the new species and the related species, Dendrobium flexicaule , and its endangered status are discussed.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 217–221.  相似文献   

15.
濒危药用植物桃儿七的生物学特性及其保育措施   总被引:5,自引:0,他引:5  
桃儿七为重要抗癌药物前体物来源物种,现正处在濒危状态,已被列为国家三级保护植物。本文全 面地综述了桃儿七的生物学特性,包括外部形态、地理分布、系统位置、生态学和群落学特性、发育生物学、繁 殖生物学、植物化学、细胞组织培养和内生真菌研究以及遗传学等研究。最后分析了引起桃儿七濒危的原因, 并提出了具体保育措施和研究展望。  相似文献   

16.
Chlorophytum arundinaceum is an important medicinal plant and its tuberous roots are used for various health ailment treatments. It has become an endangered species in the Eastern Ghats, and a rare medicinal herb in India, due to its excessive collection from its natural habitat and its destructive harvesting techniques, coupled with poor seed germination and low vegetative multiplication ratio. In order to contribute to its production systems, an efficient protocol was developed for in vitro clonal propagation through shoot bud culture. For this, multiple shoots were induced from shoot bud explants on Murashige and Skoog's medium supplemented with 2.5-3.0 mg/L BAP, 0.01-0.1 mg/LNAA and 3% (w/v) sucrose. Inclusion of Adenine Sulphate (25mg/L) in the culture medium improved the frequency of multiple shoot production and recovered the chlorotic symptoms of the leaves. Media having pH 5.9 and 4% sucrose showed significant improvement on shoot bud multiplication and growth. In vitro flowering was observed when the subcultures were carried out for over four months in the same multiplication media. Rooting was readily achieved upon transferring the shoots on to half- strength MS medium supplemented with 0.1 mg/L IBA and 2% (w/v) sucrose. Micropropagated plantlets were hardened in the green house, successfully established, and flowered in the field. This method could effectively be applied for the conservation and clonal propagation to meet the demand of planting materials.  相似文献   

17.
To investigate distribution, habitat characteristics, and current conservation status of the endangered endemic species, rapid small gudgeon Microphysogobio rapidus (Cyprinidae), we surveyed a total of 79 sites from the historic records (20 sites) plus additional sites (59 sites) with good habitat conditions, analyzed their sites, and compared them with historic recorded sites to reveal the factors of extinction threats and causes. We found only eight out of 79 sites in the Nam River areas. The habitats were greatly reduced and restricted compared with the historic sites, which mainly cause from habitat modification, such as various types of river renovations at the main stream and tributary streams of the Nakdong River. The present habitats are higher water temperature and more number of fish species than the absent ones, but conductivity, total nitrogen, and number of weir are lower. In addition, the present sites are lower low velocity at pool and higher mean substrate at pool. From this study, we suggest that maintaining good water quality and preventing anthropogenic impacts greatly aid conservation of the M. rapidus in South Korea.  相似文献   

18.
Tropical montane forests are known to support many endemic species with restricted geographic ranges. Many of these species are however, faced with numerous threats, most notably from habitat loss and degradation, invasive alien species, and climate change. Examples include Taita Apalis and Taita Thrush. Taita Apalis (Apalis fuscigularis) and Taita Thrush (Turdus helleri) are species of birds listed as Critically Endangered by the Government of Kenya and the International Union for Conservation of Nature (IUCN). They are endemic to Taita Hills’ cloud forests in southeastern Kenya and protected under Wildlife Conservation and Management Act. As they face high risk of extinction, exploring their habitat suitability is imperative for their protection. To determine the current spatial distribution and the key ecogeographical explanatory factors and conditions affecting species distribution and indirect effects on species survival and reproduction, we employed Maximum Entropy (MaxEnt) modelling. This study was conducted in Ngangao and Vuria forests in June and July 2019 and 2020. Ngangao forest is gazetted as forest reserve and managed by the Kenya Forest Service whereas Vuria is non-gazetted and thus remains without official protection status. Ecogeographical explanatory variables; climatic, remote sensing-, LIDAR-, topography- and landscape-based variables were used in modelling and separate models were produced. 23 occurrence records of Taita Apalis and 30 of Taita Thrush from Ngangao and 21 of Taita Apalis from Vuria forests were used in the modelling. According to the models, less than 7% of the total area of Ngangao and Vuria forests was predicted as suitable habitat for Taita Apalis and Taita Thrush. This shows that these two species are more vulnerable to extinction from demographic stochasticity. Consequently, managing their habitats is critical for their long-term persistence. LIDAR-based canopy height range and elevation greatly influenced Taita Apalis distribution in Ngangao forest, with areas of high elevation (1620–1750 m a.s.l.) and having open middle-storey preferred. Elevation, slope and topographic wetness index (twi) were the major determinants of Taita Thrush distribution in Ngangao, where gentle sloping areas with moderately dry surfaces within high elevation (1620–1730 m a.s.l.) were favoured. Mean annual temperature, Euclidean distance to the forest edge, slope and land cover type greatly influenced the distribution of Taita Apalis in Vuria, with gentle sloping areas within forest interior made up of indigenous vegetation preferred. This study proposes reforesting open and degraded sites next to areas predicted as highly suitable for the two species; establishment of agroforestry belts based on indigenous trees on the boundaries of the two forests to reduce grazing and firewood collection pressure and enhance resilience to the edge effects; and enhancing forest protection through Participatory Forest Management.  相似文献   

19.
AimEurope''s only globally critically endangered seabird, the Balearic shearwater (Puffinus mauretanicus), is thought to have expanded its postbreeding range northwards into UK waters, though its at sea distribution there is not yet well understood. This study aims to identify environmental factors associated with the species’ presence, map the probability of presence of the species across the western English Channel and southern Celtic Sea, and estimate the number of individuals in this area.LocationThe western English Channel and southern Celtic Sea.MethodsThis study analyses strip transect data collected between 2013 and 2017 from vessel‐based surveys in the western English Channel and southern Celtic Sea during the Balearic shearwater''s postbreeding period. Using environmental data collected directly and from remote sensors both Generalized Additive Models and the Random Forest machine learning model were used to determine shearwater presence at different locations. Abundance was estimated separately using a density multiplication approach.ResultsBoth models indicated that oceanographic features were better predictors of shearwater presence than fish abundance. Seafloor aspect, sea surface temperature, depth, salinity, and maximum current speed were the most important predictors. The estimated number of Balearic shearwaters in the prediction area ranged from 652 birds in 2017 to 6,904 birds in 2014.Main conclusionsAreas with consistently high probabilities of shearwater presence were identified at the Celtic Sea front. Our estimates suggest that the study area in southwest Britain supports between 2% and 23% of the global population of Balearic shearwaters. Based on the timing of the surveys (mainly in October), it is probable that most of the sighted shearwaters were immatures. This study provides the most complete understanding of Balearic shearwater distribution in UK waters available to date, information that will help inform any future conservation actions concerning this endangered species.  相似文献   

20.
Here we describe the characterization of six polymorphic microsatellite loci for Lilium philadelphicum (Liliaceae). Polymorphism levels ranged from 7 to 30 alleles per locus with a mean number of 15 alleles per locus. Observed heterozygosity (HO) ranged from 0.17 to 0.82 and did not deviate from Hardy–Weinberg expectations in the three western Montana populations included in the analysis. These loci are proving useful in studying gene flow between populations of this species distributed across its range in North America.  相似文献   

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