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1.
鄱阳湖南矶山湿地自然保护区的外来入侵植物调查与分析   总被引:2,自引:1,他引:1  
为了解鄱阳湖南矶山自然保护区外来入侵植物的状况, 从2010 年至2014 年对外来入侵植物的物种种类、分布、传播等进行了调查。结果表明, 南矶山湿地保护区共有外来入侵植物32 种, 隶属于l8 科28 属, 其中菊科最多, 有8 种6 属;其次是苋科, 有4 种3 属, 绝大多数是草本植物;以原产地为美洲的最多, 有15 种, 其中来自北美的有9 种。对保护区造成严重危害的外来入侵植物有5 种, 分别为野燕麦(Avena fatua)、小飞蓬(Conyza canadensis)、野胡萝卜(Daucus carota)、裸柱菊(Soliva anthemifolia)和空心莲子草(Alternanthera philoxeroides), 危害较强的主要有7 种, 危害较轻的有20 种。对外来植物的入侵途径、规律与成因以及对生态环境造成的影响进行了讨论, 并提出了防治对策与建议。  相似文献   

2.
就地保护中实施迁地保护是濒危物种保护的较为有效的形式。扎龙保护区自1976年筹建以来,就计划并开展了以人工辅助繁育丹顶鹤(Grus japonensis)种群为平台的孵化、训飞、放飞工作,本文通过常规的统计方法对扎龙保护区自建区以来的丹顶鹤孵化、训飞、放飞数据进行了分析。结果显示,建区至今,人工辅助繁育丹顶鹤种群的年均孵化成功率为77.41%(1981年最高,为100%);孵化成活量整体呈上升趋势,年均约为27只(2003年最高,为52只),近10年来基本维持在30~50只之间;训飞规模在逐年提高,近年来基本维持在100~120只之间;放飞规模与训飞规模同步也在逐年提高,年均放飞8只,2009年以来维持在10只以上;放飞野化的丹顶鹤已记录于中国的江苏盐城保护区、山东黄河三角洲保护区、韩国铁原地区。进一步分析表明,扎龙保护区在丹顶鹤保护方面已取得了一定的成绩。  相似文献   

3.
明确物种繁殖栖息地的潜在分布对于受胁物种的保护与科学管理具有十分重要的意义。扎龙保护区是国际濒危物种丹顶鹤西部迁徙种群的主要繁殖地之一,近年来繁殖种群数量波动较大。通过GIS空间技术平台,利用MAXENT模型,结合2012—2013年丹顶鹤(Grus japonensis)营巢分布点和环境特征变量,对扎龙保护区丹顶鹤营巢生境的适宜性进行了分析。结果表明:模型的评价效果达到优秀水平(训练集AUC=0.901);绿度(34.9%)、距道路距离(17.1%)、土壤湿度(16.3%)、海拔(15.7%)是丹顶鹤营巢生境的主要环境特征变量;核心区中部和南部是丹顶鹤主要的适宜营巢分布区,缓冲区和实验区有少量的适宜营巢区分布,丹顶鹤适宜营巢生境面积为35857.35hm~2,占保护区总面积的17.07%。建议在重点管理核心区的同时,对缓冲区和实验区的小面积芦苇沼泽给予更多关注。  相似文献   

4.
2017年3月—2018年3月期间,采用红外相机技术调查了桃红岭梅花鹿国家级自然保护区内鸟类和兽类的物种多样性。红外相机监测期间,共累计4442个相机日,获得野生动物独立有效照片1003张,其中兽类独立有效照片683张,共4目9科16种;鸟类独立有效照片320张,共9目23科46种;保护区内兽类相对丰富度最高的是小麂(Muntiacus reevesi),鸟类丰富度最高的是黑领噪鹛(Garrulax perspicillatus);其中国家Ⅰ级保护动物有2种,梅花鹿(Cervus nippon)和白颈长尾雉(Syrmaticus ellioti);国家Ⅱ级保护动物有6种,分别为小灵猫(Viverricula indica)、勺鸡(Pucrasia macrolopha)、白鹇(Lophura nycthemera)、草鸮(Tyto longimembris)、红角鸮(Otus sunia)和松雀鹰(Accipiter virgatus)。红外相机在灌丛中拍摄率最高,在草甸中拍摄率最低。通过稀疏外推曲线对物种多样性进行估计可得,保护区实际的物种数远大于监测到的物种数,因此有待继续进行长期监测。通过物种与相机位点的PCA排序图可知,各个相机位点和物种的相关性较强。调查结果为保护区提供了重要的兽类和鸟类资源信息,为保护区对野生动物的有效管理和长期监测提供了数据支持。  相似文献   

5.
为探讨广东翁源青云山自然保护区植被的生境适应性和竞争机制,对青云山自然保护区森林群落优势树种的生态位特征进行了分析。结果表明,群落优势种的重要值之和为49.01,其中杉木(Cunninghamia lanceolata)的重要值最大,毛竹(Phyllostachys edulis)的变异系数最大。优势种的Levins和Shannon生态位宽度较为一致,罗浮柿(Diospyros morrisiana)、栲(Castanopsis fargesii)、木荷(Schima superba)、鼠刺(Itea chinensis)和罗浮锥(C.faberi)的生态位宽度较大,而毛竹、杉木、黧蒴锥(C.fissa)和华润楠(Machilus chinensis)的生态位宽度相对较窄。所有物种对间的生态位重叠度和生态位相似性较小,表明共存物种的种间竞争不激烈,因而群落处于相对稳定的状态。生态位宽度与重要值的关系不显著,而与重要值变异系数呈显著的负相关关系,表明重要值变异系数是影响生态位宽度的重要因素。这为青云山自然保护区森林资源的保护和管理提供重要的科学依据。  相似文献   

6.
O. Ciancio 《Plant biosystems》2013,147(2):411-418
Abstract

Classic silviculture and management, with the aim of predicting regeneration rate and producing a constant yield of merchantable wood, have simplified many forests, often transforming natural forests into plantations or coppices. To conserve forest complexity and biodiversity, silviculture and forest management should change the reference paradigm and consider forest ecosystems as complex biological systems characterized by the inherent unpredictability of their trajectories in a continuously changing environment. The new Management Plan for the Vallombrosa Forest (Florence, Italy), a State Nature Reserve and a Natura 2000 Site, is based on this approach. The aim is the gradual evolution of the pure silver fir stands toward mixed stands with a complex structure. Most of the species considered by Natura 2000 depend on an increase of structural diversity at different space and time scales. The management approach proposed by the new plan is coherent with this aim and thus biodiversity conservation is not in conflict with forest management but is, instead, a direct consequence of the systemic approach.  相似文献   

7.
Population size and distribution data for wildlife species play an important role in conservation and management, especially for endangered species. However, scientists seriously lack data on the population status of many species. The northern yellow-cheeked gibbon (Nomascus annamensis) is found in southern Lao PDR, central Vietnam, and northeastern Cambodia. The population of the species has significantly declined due to hunting, habitat loss, and the wildlife trade. To examine the population size and distribution of N. annamensis, we conducted a field survey in Song Thanh Nature Reserve, Quang Nam Province, central Vietnam from February to April 2019 using the audio point count method. We combined Distance Sampling and Ecological Niche Modeling to estimate the population of the gibbons. Results showed that the total suitable area for the gibbons was about 302.32 km2, with the two most important variables of the habitat model being the distance-to-villages and forest type. We detected 36 gibbon groups through field surveys and estimated 443 (95% CI, 278–707) gibbon groups in Song Thanh Nature Reserve. Our results indicate that the gibbon population in Song Thanh Nature Reserve is the largest known population of N. annamensis in Vietnam. In addition, our study was the first to combine species distribution modeling with distance sampling to estimate gibbon density and population size. This approach might be useful in surveying and monitoring gibbon populations because it takes imperfect detection probability into account in estimating gibbon population density while estimating the area of potential habitat using environmental variables.  相似文献   

8.
Plantation and secondary forests form increasingly important components of the global forest cover, but our current knowledge about their potential contribution to biodiversity conservation is limited. We surveyed understory plant and carabid species assemblages at three distinct regions in temperate northeastern China, dominated by mature forest (Changbaishan Nature Reserve, sampled in 2011 and 2012), secondary forest (Dongling Mountain, sampled in 2011 and 2012), and forest plantation habitats (Bashang Plateau, sampled in 2006 and 2007), respectively. The α‐diversity of both taxonomic groups was highest in plantation forests of the Bashang Plateau. Beetle α‐diversity was lowest, but plant and beetle species turnover peaked in the secondary forests of Dongling Mountain, while habitats in the Changbaishan Nature Reserve showed the lowest turnover rates for both taxa. Changbaishan Nature Reserve harbored the highest proportion of forest specialists. Our results suggest that in temperate regions of northern China, the protected larch plantation forest established over extensive areas might play a considerable role in maintaining a high biodiversity in relation to understory herbaceous plant species and carabid assemblages, which can be seen as indicators of forest disturbance. The high proportion of phytophagous carabids and the rarity of forest specialists reflect the relatively homogenous, immature status of the forest ecosystems on the Bashang Plateau. China's last remaining large old‐growth forests like the ones on Changbaishan represent stable, mature ecosystems which require particular conservation attention.  相似文献   

9.
  1. Being the largest extant amphibian in the world, the IUCN Critically Endangered Chinese giant salamander Andrias davidianus is a charismatic species with great international public interest. While threats such as commercial overexploitation and habitat degradation have been extensively documented to affect natural populations of A. davidianus, still no information is available about the species sensitivity to climate change.
  2. Here, we develop an ensemble of species distribution models (SDMs) for A. davidianus and projected its habitat suitability under present-day and future climate change scenarios. We based our SDMs on bioclimatic and topographic predictors, and recent (2012–2018) field-collected occurrence data across the whole distribution range of the species.
  3. The ensemble SDMs exhibited good predictive capacity and suggested that slope, maximum temperature of warmest month, precipitation of driest month, and isothermality are the most influential predictors in determining distribution patterns in this species. The projections of our models point to a pronounced impact of climate changes over A. davidianus, with more than two-thirds of its suitable range expected to be lost in all scenarios of future climates tested.
  4. In concert with the numerous other threats that are affecting this species, climate change poses a serious hindrance to the long-term survival of A. davidianus. We emphasise the urgent need of undertaking strict measures to manage this species and safeguard the few remaining available suitable habitats. We suggest that adaptive management strategies including designation of new reserves should be considered to mitigate the impacts of climate change on A. davidianus.
  相似文献   

10.
The Abe Bailey Nature Reserve, South Africa has been identified as a potential community resource reserve compatible with biodiversity conservation. As part of the planning and public participation phase this study investigated the potential for sustainably harvesting medicinal plants. Medicinal plant use data on local species, parts used and harvesting techniques, in collaboration with neighbouring traditional healers were collected. A census of these plants was conducted in the reserve and frequency, density and abundance were calculated. A medicinal plant rating system for assessing conservation priorities was used to combine both social-qualitative and ecological-quantitative data. Five medicinal species suitable for high impact harvesting were identified. Thirty-four species have potential to be set up as harvesting trials to determine sustainable quotas. Thirty-one medicinal species including Boophane disticha, Dicoma anomala, Eucomis autumnalis, Hypoxis hemerocallidea, Pentanisia prunelloides and Indigofera daleoides are considered to be site-specific sensitive species and should not be harvested from the reserve. Following this research an on site nursery has been started at the reserve. A multi-pronged approach involving harvesting trials, propagation and plant rescue from developments to cope with escalating demand and dwindling natural populations needs to be implemented.  相似文献   

11.
该文报道了在云南省马关县古林箐省级自然保护区发现的一个云南省新记录种——皱皮油丹(Alseodaphne rugosa Merr.et Chun),并对其形态、生境及该新记录种的生物地理学意义进行了描述与讨论。此新记录种的发现对樟科油丹属植物的系统分类学、生物地理学和区域生物多样性等方面的研究具有重要意义,同时也为探讨海南岛的起源问题提供了具有价值的研究材料。  相似文献   

12.
为了解日益恶化的喀斯特环境下叶附生苔类植物的分布状况,对广西中越边境喀斯特地区叶附生苔类植物多样性展开调查。结果表明,广西中越边境喀斯特地区有叶附生苔类植物5科15属43种,其中,九洲疣鳞苔(Cololejeunea yakusimensis)、巴氏薄鳞苔(Leptolejeunea balansae)、斯氏唇鳞苔(Cheilolejeunea streimannii)、麦氏细鳞苔(Lejeunea micholitzii)、巨齿细鳞苔(L.kodamae)和纤细细鳞苔(L.exilis)为广西苔藓植物新记录。该地区叶附生苔类植物区系具有热带性质和东亚分布特点。与邻近地区比较,该地区叶附生苔类植物与贵州茂兰的亲缘关系和区系关系最紧密。该地区叶附生苔类植物分布随海拔增加呈增加趋势。那坡老虎跳保护区、龙州和宁明弄岗保护区以及靖西龙邦镇风水林是叶附生苔类植物分布最丰富的地区,因此,建议应对这些地区的叶附生苔类植物进行优先保护。  相似文献   

13.
通过多次野外调查及资料整理,对纳板河流域国家级自然保护区蕨类植物的区系组成、地理成分、区系联系、性质及起源等方面进行了分析研究。结果显示:(1)纳板河保护区共有蕨类植物43科90属239种,优势科为水龙骨科、金星蕨科、凤尾蕨科、蹄盖蕨科、三叉蕨科,优势属为凤尾蕨属、鳞盖蕨属、毛蕨属、石韦属。(2)纳板河保护区蕨类植物区系具有明显的热带向亚热带过渡的性质,当属热带亚洲蕨类植物区系,但在一定程度上受到中国-喜马拉雅蕨类植物区系的影响。(3)纳板河保护区在地理亲缘关系上与云南大围山最为密切,与海南岛、哀牢山保护区的关系次之,与苍山、轿子雪山及雕林山保护区的联系较为疏远。  相似文献   

14.
为探讨喀斯特地区森林群落的演替动态和生物多样性维持机制,采用样地调查法对草海国家级自然保护区的华山松(Pinusarmandii)群落的物种组成、植物区系特征、种群结构和物种多样性等进行了分析。结果表明,样地内共有种子植物37科69属81种,其中乔木11种、灌木32种、草本38种;群落内植物的科、属区系成分类型多样,以温带成分为主;生活型谱主要以高位芽植物(46.91%)和地面芽植物(27.16%)为主;乔木层华山松的重要值达58%,为群落的单优势种;径级结构呈左偏正态型分布,树高分布集中在12~21 m,冠幅分布呈V型;乔木层与灌木层、草本层间的多样性差异显著(P0.05),物种丰富度指数S和D_M、多样性指数H和D_S均为草本层灌木层乔木层,物种均匀度指数J为灌木层草本层乔木层。因此,草海国家级自然保护区内的华山松群落特征和物种多样性具有明显的地域特点。  相似文献   

15.
该研究通过样方调查法对卡拉麦里山有蹄类野生动物自然保护区(卡山自然保护区)水源地植物种类及数量进行统计,利用TWINSPAN和DCA进行植物群落数量分类和排序,并对保护区典型水源地土壤理化性质与植物群落物种多样性指数的相关关系进行CCA分析。结果表明:(1)卡山自然保护区32个典型水源地调查共记录到15科41属53种植物。(2)群落分类共分为7个群落,分别为:铃铛刺群落、沙拐枣-麻黄群落、白刺+柽柳-蛇麻黄+羽毛三芒草群落、芨芨草+白茎绢蒿群落、盐爪爪群落、白刺群落、柽柳+盐爪爪-芨芨草群落。(3)有机质、总氮对植物群落的分布影响较大。研究认为,典型水源地作为重要的功能区域,对其进行保护是维持卡山保护区生态平衡的一个重要环节。  相似文献   

16.
In this study, an ecological vulnerability assessment indicator system was constructed using the “exposure–climate sensitivity–adaptive capacity” framework according to the theory of ecological vulnerability. An improved ecosystem service value calculation model was proposed based on empirical parameters. Using Yancheng Nature Reserve in China as an example, we employed remote sensing data to conduct an empirical analysis of the changes in the spatiotemporal pattern, ecological vulnerability, and ecosystem services of typical landscape types over the period from 1987 to 2013. The statistical results derived from landscape pattern indices (LPIs) showed that during the investigation period, three natural wetland landscape types (i.e., Spartina alterniflora, Suaeda glauca, and Phragmites australis) showed gradually increased fragmentation in the study area. The ecological vulnerability scores of the major landscape types (in descending order) were P. australis (0.053), farmland (0.047), S. alterniflora (0.042), S. glauca (0.031), and bare mud flat (0.002). The results derived from the ecosystem service value fluctuation index (ESVFI) showed that from 1987 to 1997, the value of the ecosystem services provided by S. glauca and P. australis wetlands decreased, whereas that of S. alterniflora wetlands increased continuously. From 2002 to 2013, the value of the ecosystem services provided by all three types of natural wetland showed a downward trend. In conclusion, the combined effects of human and natural factors, including the expansion of farmland and the invasion of S. alterniflora, and changes in seawater erosion and deposition led to changes in the landscape patterns, ecological vulnerability, and ecosystem services of the Yancheng Nature Reserve during the investigation period. The results indicate that a “dual adaptive” management system based on natural succession and supplemented by appropriate manual intervention should be implemented, and the management efficiency and flexibility should be improved to meet the common needs of biodiversity conservation and economic development.  相似文献   

17.
不同林分类型对昆虫群落多样性的影响   总被引:1,自引:0,他引:1  
为研究近自然森林经营下的华北落叶松人工林不同林分类型对昆虫群落多样性的影响,以塞罕坝自然保护区内的华北落叶松纯林和混交林作为研究对象,对6种不同林分类型中的昆虫群落结构进行了研究。共获得昆虫标本9542头,隶属于7目,68科,187种,以双翅目、半翅目和鞘翅目为优势类群。研究结果表明:6种林分类型中的昆虫在物种和个体数上存在差异,相似性分析显示群落结构均不相似;群落多样性指数分析表明华北落叶松纯林和其它类型的混交林均具有较高的丰富度指数和多样性指数;主成分分析表明各林分类型中捕食性类群和寄生性类群是影响昆虫群落结构的主要因素,且捕食性类群和寄生性类群对植食性类群的控制作用较强;稳定性分析显示6种林分类型昆虫群落结构均具有较高的稳定性。  相似文献   

18.
气候变化将会对森林树种结构、空间结构以及林龄结构等产生重大影响,准确预测森林景观演替对未来气候变化的响应,不仅能够为科学管理森林生态系统提供理论依据,而且对制定生物多样性保护与珍稀物种保护策略也具有重要意义。本文运用LANDIS Pro 7.0与LINKAGES模型,模拟天宝岩国家级自然保护区8个树种在2种不同气候变化情景(RCP4.5和RCP8.5)下未来300年的森林植被演替动态,分析森林景观格局变化特征及其对气候变化的响应。结果表明:毛竹、马尾松、猴头杜鹃、长苞铁杉以及杉木的潜在面积分布与景观格局指数对气候变化的响应较为显著。在气候变化情景下,各树种的景观分维度均介于1.03—1.08,保护区内各景观斑块相对简单规则。毛竹、猴头杜鹃和杉木聚集度下降趋势明显而斑块密度显著上升,长苞铁杉随演替进行面积逐渐减少而聚集度相对较高且斑块密度剧增,马尾松斑块密度缓慢增加而聚集度先降后升,随气候变化这些树种的景观完整度都遭到了不同程度的破坏,且在RCP8.5气候情景下景观破碎化更严重。而气候变化对阔叶林与柳杉的影响则较小,且阔叶林在演替期间斑块密度下降而聚集度稳中有增,潜在面积分布呈现出良好的...  相似文献   

19.
Understanding genetic diversity patterns of endangered species is an important premise for biodiversity conservation. The critically endangered salamander Andrias davidianus, endemic to central and southern mainland in China, has suffered from sharp range and population size declines over the past three decades. However, the levels and patterns of genetic diversity of A. davidianus populations in wild remain poorly understood. Herein, we explore the levels and phylogeographic patterns of genetic diversity of wild‐caught A. davidianus using larvae and adult collection with the aid of sequence variation in (a) the mitochondrial DNA (mtDNA) fragments (n = 320 individuals; 33 localities), (b) 19 whole mtDNA genomes, and (c) nuclear recombinase activating gene 2 (RAG2; n = 88 individuals; 19 localities). Phylogenetic analyses based on mtDNA datasets uncovered seven divergent mitochondrial clades (A–G), which likely originated in association with the uplifting of mountains during the Late Miocene, specific habitat requirements, barriers including mountains and drainages and lower dispersal ability. The distributions of clades were geographic partitioned and confined in neighboring regions. Furthermore, we discovered some mountains, rivers, and provinces harbored more than one clades. RAG2 analyses revealed no obvious geographic patterns among the five alleles detected. Our study depicts a relatively intact distribution map of A. davidianus clades in natural species range and provides important knowledge that can be used to improve monitoring programs and develop a conservation strategy for this critically endangered organism.  相似文献   

20.
The species composition of the herbaceous layer was surveyed in eight plant communities with a small-quadrat method. Ordination techniques were applied to these data to identify relative homogenous grazing areas, assess the veld condition of each unit and to identify indicator species, based on a grazing gradient. Five relative homogenous grazing areas were identified and should be treated as such for management purposes. The veld in the Nylsvlei Nature Reserve was generally in a good condition due to the low stocking densities of game (≈0.29 animals ha?1) which have been maintained for many years. Nine indicator species, i.e. Cynodon dactylon, Digitaria eriantha, Ischaemum afrum, Leersia hexandra, Oryza longistaminata, Setaria sphacelata, Sporobolus ioclados, Sporobolus pyramidalis, and forbs, were identified which may be used for future monitoring of veld condition in the different vegetation units.  相似文献   

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