首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 171 毫秒
1.
重庆大木山木本植物区系及植物资源特点   总被引:3,自引:0,他引:3  
基于野外调查资料,对位于三峡库区腹心地带的大木山的木本植物区系及资源特点进行研究,以期为该地区生物多样性保护和可持续利用提供依据.野外调查共发现木本植物738种,隶属于86科、288属.其中裸子植物6科、10属、15种,双子叶植物77科、271属、699种,单子叶植物3科、7属、24种.乔木268种,灌木398种,木质藤本72种.科的组成优势现象十分明显,含10种以上的科有26个,包含164属、526种植物,分别占该区木本植物总属数和总种数的56.94%和71.27%,是该区木本植物区系构成的主导成分.木本植物区系成分复杂,属的分布类型有14个,种的分布类型有12个,区系具有明显的过渡性特征.有483个中国特有种分布于该地区,占总种数的65.71%,其中27.12%的物种为华中植物区特有种.13个地区的聚类分析表明大木山与华中植物区和华东植物区关系最为密切.木本植物资源以药用、材用、观赏、食用类为主,古老孑遗植物和珍稀濒危植物丰富.图l表5参35  相似文献   

2.
九顶山西坡汶川段维管植物区系研究   总被引:3,自引:1,他引:2  
汶川是"五·一二"特大地震的中心地带,也是受灾最为严重的区域.本文基于震前3 a的实地调查资料,对龙门山脉主峰--九顶山西坡汶川段的植物区系进行了系统分析,以期为灾后生物多样性的监测评估提供依据.在对九顶山西坡汶川雁门沟的野外调查中共发现维管植物111科、363属、733种,其中有种子植物94科、333属、687种.科的物种丰富性很高,含10种以上的种子植物科有19个,含216属、455种植物,分别占该区维管植物总属数和总种数的59.50%和62.07%,是该区植物区系构成的主导成分.种子植物区系成分复杂,15种分布类型在该区均有分布;温带分布的属和种远远超过热带分布类型,体现了该植物区系明显的温带性质.在东亚分布类型中,属于中国-喜马拉雅类型的属和种所占比例远远高于中国-日本成分,说明九顶山虽处于中国-喜马拉雅森林植物亚区与中国-日本森林植物亚区的交界线附近,但其西坡汶川段依然属于中国-喜马拉雅森林植物亚区的范畴.有367个中国特有种分布于该区,占物种总数的53.42%,其中半数以上的物种属于中国西南特有种或横断山区特有种,进一步证明中国西南高山区特别是横断山地区是温带植物物种的分化中心这一事实.图1表5参11  相似文献   

3.
双台河口自然保护区滨海湿地的维管束植物区系特征   总被引:1,自引:0,他引:1  
辽宁双台河口自然保护区滨海湿地维管束植物区系中有56科117属155种维管束植物,有蔷薇科、菊科、禾本科、蓼科、豆科、唇形科、香蒲科、眼子菜科、莎草科等9大科51属76种,9大科的属数、种数占区系总属数和总种数的43.59%、49.03%;区系内小科、单种属多,说明科、属的分化程度较高。区系中有15种盐生植物、25种水生植物、34种湿生植物、79种中生植物和4种旱生植物,湿地植被的优势种和建群种均为盐生植物、水生植物和湿生植物,这表明保护区内滨海湿地植被的形成不仅受海水、土壤盐渍化影响,更受辽河径流淡水的影响。区系中有地面芽植物、地下芽植物72种,占总种数的46.45%,说明冷湿气候对保护区内滨海湿地植被的形成有重要作用。区系中有世界分布属31属,占区系总属数的26.50%,这反映了湿地植被的隐域性;有温带分布属57属、热带分布属23属,分别占区系总属数的48.72%、19.66%,这分别表明保护区滨海湿地植被具有一定的地带性特征,雨量充沛、冬季气温较高的海洋性气候特征对湿地中起源于热带的维管束植物生存限制较小。  相似文献   

4.
括苍山省级自然保护区是浙江省内少有的一个天然植物"基因库"和"植物博物馆"。2016年,在括苍山省级自然保护区建立了1 hm2的森林动态监测样地,完成了第1次野外调查,并从物种组成、区系特征、径级结构和空间分布格局等方面分析了其群落特征。结果显示:样地内有维管植物68科126属194种。其中乔木层胸径≥1cm的木本植物36科67属121种;热带性质的科和属分别占总科和属数的66.67%和59.70%,温带性质的科和属分别占33.33%和38.81%。样地内国家Ⅰ、Ⅱ级重点保护野生植物分别有1和2种。列入《中国生物多样性红色名录:高等植物卷》中的"近危"以上等级的物种10种,被列入《濒危野生动植物种国际贸易公约》(CITES)附录Ⅱ1种,中国特有种53种,具有良好的保护和研究价值。稀有种23种,占总树种数的19.01%。重要值最大的为甜槠(Castanopsis eyrei)8.69%,其次为鹿角杜鹃(Rhododendron latoucheae)6.80%和木荷(Schima superba)5.92%。平均胸径为6.95 cm,小径级木较多。空间分布格局分析结果表明,不同的物种在空间分布上存在一定的规律。  相似文献   

5.
云南地区中国种子植物特有属的研究   总被引:1,自引:0,他引:1  
冯建孟  朱有勇 《生态环境》2010,19(3):621-625
物种特有现象的研究具有重要的区系地理学和保护生物学意义。利用大尺度的植物物种分布信息,探讨了云南地区中国种子植物特有属的科、属组成,区系性质及其地理分布格局。结果表明,云南地区拥有中国种子植物特有属125属,分属于59科,共含种子植物246种,是中国种子植物特有属的重要分布地区之一。含特有属较多的科主要为菊科Compositae、苦苣苔科Gesnefiaceae、伞形科Umbelliferae、禾本科Gramineae和唇形科Labiatae。从各属所包含的物种数来看,单型属占主体地位。根据科的分布区类型构成,云南地区中国种子植物特有属主要起源于热带地区。从属的生活型构成来看,主要以草本植物属为主,而木本植物属所占比重相对较小,暗示着研究区域内特有属的区系兼有年轻成分和古老成分,但以年轻成分为主。从空间分布格局来看,特有属主要分布在“田中线”以东地区。与过去的研究结果不同,我们发现云南地区拥有3个重要的特有属分布中心和3个次级分布中心。  相似文献   

6.
德夯风景区位于湖南省西北部吉首市之西,海拔189.4m-964.6m, 面积252km~2。该区蕨类植物有28科,51属,118种。其特点:(1)、种类丰富而密度大,以鳞毛蕨科、水龙骨科、蹄盖蕨科、卷柏属、铁角属、凤尾蕨属等为优势类群,科内、属内种数贫乏;(2)、属的地理成分以热带成分为主,温带与亚热带成分次之,无特有属。种的地理成分以亚热带成分为主,热带与温带成分次之,特有种类丰富;(3)、东亚成分(尤其是中国-日本成分)众多,可能是东亚成分分布中心的一部分;(4)、与天平山、佼母溪关系最密切,与庐山、黄山、大瑶山关系较密切,与神农架、鼎湖山较疏远。  相似文献   

7.
香果树(Emmenopterys henryi)为中国特有的孑遗植物,国家Ⅱ级保护植物。参照CTFS(Center for Tropical Forest Science)固定样地的调查方法,对古田山自然保护区香果树野生群落的生境特点、物种组成、群落外貌、垂直结构、生物量、物种多样性以及种群动态等进行调查。结果表明,古田山香果树群落主要分布于海拔600~850 m的沟谷地带,生长地岩石裸露度较高,部分群落盖度较高。样地内共有维管植物47科、71属、89种,植物种类较为丰富,科属组成较为分散,壳斗科、山茶科和樟科的种类相对较多;从属的地理成分看,热带分布的属与温带分布的属的比例分别为51.47%和44.12%,体现了亚热带森林的植物区系特点。群落垂直结构较为明显,可分为乔木层、灌木层和草本层,并有一定数量的层间植物;乔木层、灌木层和草本层的物种多样性大小为乔木层灌木层草本层。香果树种群的年龄结构属稳定型,但物种个体总数较少,仍需注意加强保护。该研究可为古田山香果树群落的发生、发展和演替的深入研究提供基础数据,为古田山自然保护区香果树群落濒危机制探讨、有效保护和生态系统管理提供理论支持。  相似文献   

8.
随着对保护生物多样性与消除城市化过程不利影响的日益重视,城市森林结构功能和发展变化已经引起广泛关注。本文基于对深圳特区城市森林详细大量的样方调查,对城市森林植物科属种的成分和地理分布进行了研究。结果表明特区共有植物106科289属445种;其中大戟科、棕榈科、桑科、樟科、桃金娘科、蝶形花科、茜草科、山茶科、禾本科、含羞草科和木兰科11科的属种数占多数,共占101属182种,占总属数的34.95%和总种数的40.9%;在289属中,种数最多的是榕属(18种),其次是冬青属(9种),木槿属(6种),蒲桃属(6种)和润楠属(6种),共占总属数的1.73%,总种数的10.11%。特区种子植物可戈Ⅱ分为13个分布区类型和14个变型。深圳特区城市森林中的热带成分共有220属,357种,分别占特区植物区系地理成分的80%和83.2%,可以看出,特区较发达的经济水平和快速城市化过程并没有改变其强烈的热带性质。城市森林作为城市生态系统中具有自净功能的重要组分受到了城市化的强烈干扰,不仅表现在景观水平上的生境破碎化,更重要的是在小尺度的物种组成结构中有明显反映,为生物多样性保护和城市森林后期更新与维护带来问题。  相似文献   

9.
采用野外调查方法结合典范对应分析(CCA),研究了巢湖东部湖区的入湖河道水生植被的群落结构特征和区系特征及其与环境因子的相关性.结果表明:共发现常见水生植物物种63种,隶属于28科54属,其中沉水植物4种,漂浮植物3种,浮叶植物2种,挺水植物10种,湿生植物44种.区系分析发现该区域的水生植被呈现隐域性和热带向北温带过渡的亚热带特征,植物种属主要以世界分布属和北温带分布属为主,其次是泛热带分布属,分别占总数的35.19%、31.48%和12.96%;这54属水生植物的地理分布区类型共有中国种子植物所占的15个分布区类型中的10个,而缺少5个地理分布区类型.入侵种空心莲子草(Alternanthera philoxeroides)分布广泛,河道呈现一定程度的堵塞状态;沉水植物物种则趋于单一化和分布面积狭小,尤其在水体污染严重的区域(如:双桥河流域和小柘皋河下游)几近衰退.CCA分析表明巢湖东部湖区入湖河道水生植物的空间分布主要受水体理化指标影响,而非水深的影响.总之,巢湖东部湖区入湖河道水质污染加重,水生植物群落结构极不合理、地理成分复杂程度偏低且具有明显的隐域性,沿河村镇的污水处理以及保护与恢复水生植物尤其沉水植物类群迫在眉睫.  相似文献   

10.
研究了南京紫金山大型真菌的区系成分和生态分布,以期为开展大型真菌在紫金山生态系统中的作用研究打下基础。通过2 a的实地调查,共获得大型真菌290种,分属于子囊菌和担子菌的49科120属。按所处植被环境划分,紫金山大型真菌可分为常绿-落叶阔叶混交林型、针阔混交林型、针叶林型、竹林型和灌丛荒地型;按营养类型划分,主要分为土生菌(151种)、木生菌(151种)、外生菌根菌(49种)和虫生菌(2种)等;按区系组成划分,可分为世界广布种(该分布种种数占总种数的比例为18.97%)、北温带分布种(36.89%)、北温带-澳大利亚分布种(13.45%)、温带-亚热带或热带分布种(7.59%)、欧亚大陆分布种(5.86%)、东亚-北美间断种(5.17%)、中国-日本共有种(2.07%)和中国特有种(10.00%)。  相似文献   

11.
湖南五味子科植物有2属11种2变种,分布于31个县,多生长在海拔600—1200m的山地灌丛或林中。本文依据湖南五味子科植物的地理分布,结合系统分类,植物区系和土壤资料,经分析和推论得知:1.湖南五味子科植物种质资源丰富,以中国特有种为主,它们与毗邻省区的关系密切。2.湖南五味子科植物区系表现为多种区系成分的过渡与汇集,即华南、华东、华中和滇黔桂4个区系成分的交汇、混杂和过渡。3.湖南五味子科植物的多数种类是从湖南以西地区迁移扩散而来,有的种类是从本省西北或西南以外地区而来,极少数植物在本省西南地区及其周边省区分化形成。4.湘西北至湘西南地区是湖南五味子科植物的现代分布中心,现代分化中心是湘西南地区。  相似文献   

12.
在资料分析和2013年夏秋二季进行的实地调查基础上研究了青岛市城市绿地种子植物区系的科属种构成、种的生活型构成、属的地理分布区类型构成,并比较了青岛市城市绿地种子植物区系与青岛崂山种子植物区系、中国种子植物区系属的地理分布区类型构成差异。结果表明,青岛市城市绿地种子植物区系有种子植物69科155属228种,有含5种及以上的12个较大科、124个单种属、183种木本植物和45种草本植物,有热带分布属32属、温带分布属95属、世界分布属14属和中国特有属14属。青岛市城市绿地种子植物区系有植物种类丰富多样,木本植物种类多,区系中属、种的分化程度高,属的地理分布区类型多样且具有很典型的温带特征和鲜明的中国特色等特点。  相似文献   

13.
Abstract: Habitat loss is silently leading numerous insects to extinction. Conservation efforts, however, have not been designed specifically to protect these organisms, despite their ecological and evolutionary significance. On the basis of species–host area equations, parameterized with data from the literature and interviews with botanical experts, I estimated the number of specialized plant‐feeding insects (i.e., monophages) that live in 34 biodiversity hotspots and the number committed to extinction because of habitat loss. I estimated that 795,971–1,602,423 monophagous insect species live in biodiversity hotspots on 150,371 endemic plant species, which is 5.3–10.6 monophages per plant species. I calculated that 213,830–547,500 monophagous species are committed to extinction in biodiversity hotspots because of reduction of the geographic range size of their endemic hosts. I provided rankings of biodiversity hotspots on the basis of estimated richness of monophagous insects and on estimated number of extinctions of monophagous species. Extinction rates were predicted to be higher in biodiversity hotspots located along strong environmental gradients and on archipelagos, where high spatial turnover of monophagous species along the geographic distribution of their endemic plants is likely. The results strongly support the overall strategy of selecting priority conservation areas worldwide primarily on the basis of richness of endemic plants. To face the global decline of insect herbivores, one must expand the coverage of the network of protected areas and improve the richness of native plants on private lands.  相似文献   

14.
Medically used plant species in Eastern Black Sea Region of Turkey was determined in this study. Totally 50 species within 24 families have been designated in 25 research points, using the face to face polling method with the herbs sellers and purchasers. 14 species of studied plants are endemic and pointed out as endangered species according to the IUCN list (The World Conservation Union). In which health problem the medicinal plants are used, their usage art, area and the used parts have been determined too. The research results show that 12.58% of the species are used in intestinal problems and 8.60% for diuretic. Evaluating from this point of view the region includes very rich species could be used in different health problems. The results shows that average annual income of the medically used plant selling companies is about 33,333$. Increasingly demands for the medically used plants have been raised the medically used plant companies about 60% in the last decade. The relevance of Ethnopharmacologically used plants is increasing in Turkey and in the World. Important is to meet the demand without endanger the rich plant species resources.  相似文献   

15.
Abstract: The level of endemism at a site may indicate species richness of the site. Nevertheless, assessing endemism levels in taxonomic groups such as plants may be difficult because the species richness of plants is high relative to species richness of other taxonomic groups (e.g., vertebrates). A major problem in determining whether plant species are endemic is the lack of standardization of the geographic extent of endemism: species are considered endemic to, for example, countries, continents, or states. We compiled a history of the concept of endemism as it applies to plants. The application of the concept to geographic distribution dates from the 19th century, when European explorers discovered many taxa exclusive to regions outside Europe. Two types of endemism, paleoendemism and neoendemism, were then acknowledged, according to evolutionary age, and these categories are still in use. In the 20th century, most of the research on endemism focused on explaining range restriction on the basis of cytological data, edaphic and geological factors, and phylogeny. This research led to a vast number of concepts, of which only edaphic endemism remains relatively well accepted. More recently, researchers suggest that competition may determine endemism in some cases. We suggest that plants be labeled as endemic only if their distribution occurs in a distinct ecological unit, such as a biome. On the basis of a literature review of the factors that cause range restriction, we categorized endemic taxa as paleoendemic, neoendemic, edaphically endemic, or suppressed endemic. For example, Schlechtendalia luzulifolia, is a rare forb that is a paleoendemic species of the granite and sandstone‐based grasslands of the Pampa. Levels of endemism in southern Brazilian grasslands are poorly known. We emphasize the importance of recognizing these grasslands as a single transnational biome so that levels of endemism of species therein can be assessed correctly.  相似文献   

16.
Abstract:  An important question in conservation biology is the extent to which the number of taxonomic supraspecific categories can serve as surrogates of species richness. This issue has been little explored in highly diverse areas. We used 113 floristic inventories from throughout Mexico, a megadiverse country, to evaluate the potential of higher-taxon richness for predicting local species richness of vascular plants. This large biodiversity data set includes the main vegetation types found across the country. In all, 247 families, 2,398 genera, and 11,890 species were used for the analysis, representing 99.6%, 90.2%, and 53.2% of the respective totals recorded in the country. We hypothesized that the number of genera and species would be accurately predicted by the richness of the higher taxon. To avoid getting spurious regressions resulting from the logical increase in lower-taxon richness as a higher taxon becomes richer, we calculated new response variables by subtracting from the number of elements in the lower taxon group the number of those in the higher taxon; these variables were "excess species" (number of species minus number of genera or families) and "excess genera" (number of genera minus number of families). Our results indicate that genera provide very effective surrogates for estimation of local species richness ( R 2= 0.85), whereas families have a more limited potential for this purpose ( R 2= 0.64). The predictive capacity of the diversity of higher taxon increased when the analyses were constrained to particular vegetation types (maximum R 2= 0.95 for genera). This surrogate method may be a valuable tool in locating and designing representative systems of protected areas for vascular plant diversity, especially in megadiverse countries, where conservation efforts are hindered by the lack of complete inventories and insufficient resources.  相似文献   

17.
Indicator groups may be important tools with which to guide the selection of networks of areas for conservation. Nevertheless, the literature provides little guidance as to what makes some groups of species more suitable than others to guide area selection. Using distributional data on all sub-Saharan birds and mammals, we assessed factors that influence the effectiveness of indicator groups. We assessed the influence of threatened, endemic, range-restricted, widespread, and large-bodied species by systematically varying their number in indicator groups. We also assessed the influence of taxonomic diversity by systematically varying the number of distinct genera and families within the indicator groups. We selected area networks based on the indicator groups and tested their ability to represent a set of species, which, in terms of species composition, is independent of the indicator group. Increasing the proportion of threatened, endemic, and range-restricted species in the indicator groups improved effectiveness of the selected area networks; in particular it improved the effectiveness in representing other threatened and range-restricted species. In contrast increasing the proportion of widespread and large-bodied species decreased effectiveness. Changes in the number of genera and families only marginally affected the performance of indicator groups. Our results reveal that a focus on species of special conservation concern, which are legitimate conservation targets in their own right, also improves the effectiveness of indicator groups, in particular in representing other species of conservation concern.  相似文献   

18.
南岳自然保护区兽类资源考察报告   总被引:1,自引:1,他引:1  
南岳自然保护区野生兽类动物资源丰富,共有33种,包括7目16科,属东洋界的25种,占75.8 %,属古北界的7种,占24.2 %.区内珍稀动物种类多,有大灵猫、小灵猫、野猪、穿山甲、林麝、獐等6种国家二级保护动物,12种湖南省重点保护动物.区内兽类动物由于偷猎乱捕,有些种类如华南虎、云豹已灭绝,有些动物种类已濒临灭绝,采取措施保护已刻不容缓.  相似文献   

19.
Screening plants that are hypertolerant to and excluders of certain heavy metals plays a fundamental role in a remediation strategy for metalliferous mine tailings. A field survey of terrestrial higher plants growing on Mn mine tailings at Huayuan, Hunan Province, China was conducted to identify candidate species for application in phytostabilization of the tailings in this region. In total, 51 species belonging to 21 families were recorded and the 12 dominant plants were investigated for their potential in phytostabilization of heavy metals. Eight plant species, Alternanthera philoxeroides, Artemisia princeps, Bidens frondosa, Bidens pilosa, Cynodon dactylon, Digitaria sanguinalis, Erigeron canadensis, and Setaria plicata accumulated much lower concentrations of heavy metals in shoots and roots than the associated soils and bioconcen- tration factors (BFs) for Cd, Mn, Pb and Zn were all 〈 1, demonstrating a high tolerance to heavy metals and poor metals translocation ability. The field investigation also found that these species grew fast, accumulated biomass rapidly and developed a vegetation cover in a relatively short time. Therefore, they are good candidates for phytostabilization purposes and could be used as pioneer species in phytoremediation of Mn mine tailings in this region of South China.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号