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1.
The vascular flora of the Siahrud e Rudbar protected area was investigated in the years 2007 and 2008. It is a sylvatic area in the Guilan province with a total area of approximately 28289 hectares. A total of 711 plant specimens were collected and 616 species, subspecies, and varieties, belonging to 373 genera and 101 families were identified. Of these, 14 species (23%) are endemic to Iran. The documented flora exhibited many typically Hyrcanian species, including Hyrcanian endemics. The global phytogeographical affinities of the species were as follows: Euro Siberian 212%, Iran Turanian & Euro Siberian 168%, Pluriregional 117%, Iran Turanian 106%, and Cosmopolite 55%.  相似文献   

2.
The Euxinian and the Hyrcanian floristic province are analysed in respect to their trees and shrubs. These provinces mark the southern limit of the Euro-Siberian Region in SW. Asia. Mesophyllic forests dominate; they are deciduous, but there is a substantial component of evergreen shrubs in the understorey. Characteristics species frequently have a relic nature. Species lists and some exemplary distribution maps are presented for the Euxinian and the Hyrcanian element, both with endemic and more wide-spread species, including the characteristic Euxine-Hyrcanian group.  相似文献   

3.
In this paper a critical annotated checklist of 256 endemic and near endemic species belonging to 152 genera and 50 families of flowering plants known from Hyrcanian relict forests is presented. Distribution maps of taxa, elevational range, number of known records, chorotypes, life forms, IUCN threat categories and habitat types are also provided. The chorotypes are categorized into eight main patterns: 1) the Omni-Hyrcanian pattern(OH), 2) West Hyrcanian pattern(WH), 3) Manjil-Rudbar pattern(MR...  相似文献   

4.
Due to their numerous endemic/sub‐endemic and rare plant species, rocky outcrops and cliffs, particularly those occurring at the timberline and forest/steppe ecotones of the Hyrcanian area, are considered as among the most important and fragile ecosystems in Iran. As a representative of such ecosystems, one of the last remnants of relatively undisturbed timberline and ecotone areas of the central Hyrcanian region was selected for phytogeographical, floristic and vegetation analyses. The flora and vegetation of rocky outcrops and crevices at altitudes of 2500–3000 m a.s.l. was surveyed by 40 relevés of 25 m2 surface area. A total of 215 vascular plants belonging to 55 families and 150 genera were identified in the different vegetation types. Hemicrytophytes (55.8%) were the dominant life form and Euro–Siberian/Irano–Turanian biregional plants (28.2%) were the most common chorotype at the study sites. A phytogeographical analysis indicated that Euro–Siberian elements (including Hyrcanian endemics) precede other uniregional chorotypes in the timberline and upper‐mountain parts of the central Hyrcanian area. The Caucasus, an important biodiversity hotspot close to Iran, has a considerable number of taxa in common with the Irano–Turanian floristic regions. Five vegetation types were identified using a modified TWINSPAN procedure and subsequently analysed by indirect gradient analysis applying both species‐related (species richness, life form and phytogeographical elements) and topographic/bedrocks features of the studied relevés. The analysis revealed that the vegetation of the area is mainly affected by altitude, heat index, northness, slope inclination and bedrock features.  相似文献   

5.
The natural flora of Karkamis Dam lake area and its surroundings was studied in 2000 and 2001 before the dam construction was completed. During the floristic surveys, 464 species of 279 genera belonging to 70 families were recorded. The number of endemic species is 14. The phytogeographic elements are represented in the study as follows; Irano-Turanian 104 (18.2%), Mediterranean 66 (11.5%), Euro-Siberian 7 (1.2%), Cosmopolitan 9 (1.5%), Sharo-Arabian 1 (0.1%). The phytogeographic region of 383 taxa (67.1%) is unknown, or multiregional. The spectrum of the basic life forms is as follows; Therophytes 50.0%, Hemicryptophytes 33.4%, Phanerophytes 5.2%, Geophytes 5.2%, Chamaephytes 4.3% and Hydrophytes 1.9%. According to the IUCN Red List Categories, 28 threatened plant species were identified in the study area.  相似文献   

6.
Tertiary‐relict Hyrcanian (Caspian) forest along the shores of the southern Caspian Sea is a center of biodiversity. Still, there is little information on plant diversity patterns in this area. This study evaluated plant diversity, variation in life forms, and geographical distribution of the zonal vegetation types and their relationships with environmental variables, in the educational and experimental forest of Kheyrudkenar, an important protected area in the central Hyrcanian forest of northern Iran. For this purpose, 226 vegetation plots of 400 m2 were laid out along two altitudinal transects from the lowlands (100 m a.s.l.) to the timberline (2000 m a.s.l.). Four vegetation types were identified using modified TWINSPAN, indirect and direct gradient analyses. Species‐related (species diversity indices, life form and phytogeographical elements) and environmental variables (climate, topographic and soil variables) were calculated and subjected to one‐way ANOVA among the vegetation types. Both constrained (CCA) and unconstrained (DCA) ordination analyses showed an almost identical variation of the floristic composition along their axes and demonstrated that there are two main gradients in the Hyrcanian forest. Elevation together with annual precipitation and mean annual temperature were the most important factors controlling the floristic composition in the area. Topographic features such as slope inclination and heat index were found to be important within an elevation zone/vegetation type. Soil physical and chemical properties were of secondary importance for the separation of the vegetation types. This knowledge will be useful for forest management and conservation practices in the Hyrcanian area with its distinct and unique flora and vegetation.  相似文献   

7.
海南岛尖峰岭地区种子植物区系组成及地理成分研究   总被引:14,自引:4,他引:10  
黄世能  张宏达  王伯荪   《广西植物》2000,20(2):97-106
尖峰岭地区位于海南岛西南部 ,面积约 470 km2 ,有种子植物 1 83科、90 6属、2 0 87种及变种。区系组成及地理成分分析结果表明 ,本区种子植物区系有如下特征 :(1 )科属种的组成较为丰富 ,但属内种系较贫乏、分化程度弱 ;(2 )地理成分复杂 ,以热带成分、热带亚洲成分占优势 ,特有成分也相对较丰富 ,是海南岛整体区系的重要组成部分 ;(3)区系有一定邃古性 ,本质上是华夏植物区系不可分割的一部分。  相似文献   

8.
Little is known about the soil seed bank and the influence of plant communities on the interaction between the seed bank and aboveground vegetation in the Hyrcanian temperate deciduous forest. We surveyed species composition and diversity of the persistent soil seed bank and the aboveground vegetation in six community types in old-growth Hyrcanian Box tree (Buxus hyrcana) stands in northern Iran. Fifty-two species with an average of 3,808 seeds/spores m−2 germinated; forbs accounted for 64% of the seed bank flora. Thirty-four species in the aboveground vegetation were not presented in the seed bank, 32 species in the seed bank were not found in the vegetation, and 20 species were in both. The dominant tree species were Diospyros lotus and Alnus subcordata with an average of 17 and 4.6 seeds m−2, respectively. Our results suggest that (1) vernal geophytes and shade-tolerant perennials are not incorporated in the seed bank, (2) early successional species are well represented in the seed bank, (3) plant community type has significant impacts on seed bank densities, and seed bank richness and diversity were significantly related to presence/absence of Box tree in the aboveground vegetation. The persistent seed bank contained species that potentially have a negative impact on the regeneration of forests, thus forest managers should retain old-growth Hyrcanian Box tree stands to conserve disturbance-sensitive indicator forest species.  相似文献   

9.
该研究于2019-2021年4次对安徽大别山北坡进行苔藓植物野外考察和标本采集,对采集到的1 517份标本鉴定以及文献整理,统计分析该区苔藓植物物种组成、区系地理组成;并与华东、华中、华北等地的苔藓植物区系地理组成进行比较,以明确大别山北坡苔藓植物区系的归属问题。结果表明:(1)安徽大别山北坡共有苔藓植物80科180属482种(包括种以下单位);该次调查增加了12科40属206种,其中安徽省新记录种9个。(2)发现受威胁苔藓植物2种——滇西高领藓(Glyphomitrium minutissimum)属于极危(CR),瘤根真藓(Bryum bornholmense)属于易危(VU)。(3)大别山北坡苔藓植物区系拥有3个世界性单种科,14个世界性单种属,且有34个世界性寡种属(2~6种),该区单种属和寡种属(48属)占该区总属数的26.67%,表明该区苔藓植物起源古老。(4)大别山北坡苔藓植物区系地理成分复杂多样,以北温带成分(26.43%)和东亚成分(24.89%)为主,热带亚洲成分(14.54%)次之。(5)安徽大别山北坡苔藓植物区系与华东(西天目山、清凉峰、阳际峰)区系的关系最为密...  相似文献   

10.
越南蒲马特国家自然保护区植物区系特征   总被引:1,自引:0,他引:1  
蒲马特国家公园位于越南中部的义安省,国际著名的生物多样性极为丰富的Annamite山系的核心地区。基于植物标本鉴定,在蒲马特国家公园保护区内记录有维管束植物184科,771属,2018种(包括变种和亚种)。该植物区系占整个越南植物区系的21 %,其中的木兰亚纲植物占该植物区系总种数的90 .98 %,总属数的90 .4 %及总科数的83 .7 %。含种数最多的科包括茜草科(37属/129种) ,大戟科(36/99) ,兰科(34/73) ,樟科(11/66) ,桑科(10/54) ,蝶形花科(24/51) ,壳斗科(4/50) ,紫金牛科(5/48)及芸香科(14/45)等。在种子植物地理成分组成上,有11个科的分布区类型及14属分布区类型,其中,热带分布型分别占总科数的85 .6 %和总属数的90 .1 %,并且在其热带分布属中,热带亚洲成分占总属数的31 .4 %。这些特征显示,蒲马特国家公园植物区系是典型热带性质的植物区系,属于热带亚洲植物区系的一部分。  相似文献   

11.
WU Yu-Hu 《Plant Diversity》2007,29(3):265-276
The Chaqia-Gonghe Basin and its contiguous zone is situated in eastern Qinghai of China, between latitude 34°45′- 37°00′N and longitude 98°45′- 101°30′E . Ranging from 2 800m to 5 305 m in altitude, the total area is about 38 300km2 . Its climate is continental or plateau-continental one . There are 854 species of native seed plants belonging to 59 families and 277 genera there , which occupied 37. 37% of the total species, 54 . 53% of the total genera and 65. 56% of the total families in Qinghai respectively . The floristic characteristics of the native seed plants are as follows : ( 1) Number of species and woody ones there are poor . (2) At generic level, the flora is temperate in nature, dominated by north temperate elements especially the typical elements from the warm and cold zone of Eurasia , but also with some elements of warm, cold warm and alpine ones . (3 ) The area is a margin of distribution for many species or genera especially for tropical ones, and thus , the flora of the area is clearly marginal in nature . (4) Floristic-geographically , it is a converged and transitional region for the Qinghai-Tibetan Plateau Alpine Flora , Loess Plateau Warm Flora , as well as East Asia Alpine Desert Flora. (5 ) It is a part of the Tangute Flora . (6 ) It is a key area to divide the subregions in the flora of Qinghai on the Tangute Area .  相似文献   

12.
茶卡- 共和盆地及其毗邻地区位于青海省的东部, 约处于北纬34°45′~ 37°00′, 东经98°45′~ 101°30′。海拔2 800~5 305 m, 面积约38 300 km2 , 属于高原大陆性气候类型。本区共有野生种子植物59 科、277 属、854 种。分别占青海省总科数的65 . 56%、总属数的54 .53%、总种数的37 . 37%。区系特征如下:1、种类相对较贫乏, 木本更贫乏。2、就属的层面而言, 本区属于以北温带成分, 特别是欧亚大陆温、寒地带典型成分为优势的, 兼具旱生温性、耐寒温性和高寒类型的温带区系性质。3、许多种、属和热带类型均以本区为边缘分布区, 因而区系的边缘性质明显。4、为青藏高原高寒区系、黄土高原温性( 草原)植物区系和亚洲东部荒漠区系在我国的交汇过渡区, 区系的过渡性质明显。5、是青藏高原植物亚区唐古特地区的一部分。6、是青海植物区系或“唐古特植物地区”划分植物亚地区的关键区域。  相似文献   

13.
该研究以查阅文献和野外实地调查相结合的方法,对锡林郭勒草原国家级自然保护区种子植物进行调查、统计、排序,并对该区系种子植物的种类组成、水分生态类型、生活型及种的地理成分进行分析。结果表明:锡林郭勒草原国家级自然保护区有野生种子植物856种,分别隶属于87科,345属;其中,裸子植物3科,5属,11种;被子植物84科,340属,845种。植物水分生态类型以中生植物为主,共559种,占区系总种数的65.30%;旱生植物213种,占区系总种数的24.88%。生活型以草本植物为主,占区系总种数的88.67%。区系中种的地理成分较为复杂,既反映出保护区植物地域性强的特征,也反映出该区域生境类型多样、植物丰富度高的特征。  相似文献   

14.
88 species and 20 subspecies ofCarex, altogether 94 taxa, occur in the area ofRechinger's Flora Iranica. Of these, 48 taxa, have an Euro-Siberian, 11 an Irano-Turanian and 35 a Central Asiatic distribution, the last including five species with connections to E. and tropical SE. Asia. The Saharo-Sindian element is missing. Endemic taxa are found in all groups. Eight taxa, endemic to the NW. Himalayas occur in the E. part of the area. The Euro-Siberian taxa are concentrated in the NW. of the area, but have connections to the east; similarly, Central-Asiatic taxa are concentrated in E. Afghanistan and N. Pakistan, but have connections to the west. Some Euro-Siberian taxa are widely distributed in the area, but avoid the most arid regions. The Irano-Turanian taxa are few and extend from Egypt through the area of Flora Iranica to Kazakhstan SSR and Central China.Dedicated to Hofrat Univ.-Prof. DrK. H. Rechinger on the occasion of his 80th birthday.  相似文献   

15.
澜沧江源区种子植物区系研究   总被引:1,自引:0,他引:1  
澜沧江源区位于青海省的南部,约处于北纬31°30′~33°53′,东经92°35′~97°35′。海拔3500~5900m,面积约50590km2,属于高原大陆性气候类型。本区共有野生种子植物61科、279属、996种。分别占青海省总科数的67.78%、总属数的54.92%、总种数的43.59%。区系特征如下:(1)种类相对丰富,木本较少;(2)就属的层面而言,本区属于以北温带成分,特别是欧亚大陆温、寒地带典型成分和东亚的中国.喜马拉雅高山成分为优势的高寒类型的温带区系性质;(3)许多属和多数种均以横断山地区和西藏东北部高原为传播通道而与喜马拉雅关系密切;(4)为青藏高原主体区系与横断山区系的交汇过渡区,区系的过渡性质明显;(5)是青藏高原植物亚区唐古特地区的一部分;(6)是青海植物区系或“唐古特植物地区”中植物分化比较活跃的地区之一。  相似文献   

16.
中国喀喇昆仑山地区离瓣花类植物有24科114属310种及11变种。分布种数大于60种的科有十字花科(66种)和豆科(63种),20~39种的有3科,10~19种的有4科,这9个科占该地区离瓣花类植物总属数的78.95%和总种数的88.39%,在本植物区系中占较大优势。单种属与寡种属有103属,在属级水平占绝对优势,但多种属与寡种属共含245种,在种级水平优势明显。对其地理成分分析包括8个分布区类型和14个变型,其中,温带或含温带分布的有67属194种,占该区总属数、种数的66.34%和79.18%,区系温带性质明显,且与地中海、西亚、中亚交流相对较多,而与东亚交流很少,缺乏热带分布型及中国特有分布型。与邻近区域相比,本区系与中国帕米尔高原的关系最为密切,相似系数最高,科级、属级与种级水平上,分别达82.14%、63.69%及33.86%;其次,在属级水平与阿富汗、东喜马拉雅及青藏高原相似性也分别达到17.92%、15.36%、16.26%,但种级相似性系数较低,仅为1.76%~5.69%,有一定联系。  相似文献   

17.
李保贵  朱华   《广西植物》2005,25(6):497-503,554
勐腊南贡山季风常绿阔叶林(山坡类型)1 hm2面积样地上有蕨类31种,在该森林群落草本层中占有 极其显著的地位。这些蕨类植物的地理成分分析表明它们属于亚洲热带的印度——马来西亚植物区系的一 部分,表现为东南亚热带北缘植物区系的性质,并有热带山地向亚热带山地过渡的特点。在生态表现上,它们 的生活型组成是高位芽蕨类(地生蕨种)占6.45%;地上芽蕨类12.90%;地面芽蕨类32.26%;地下芽蕨类 32.26%;附生蕨类16.13%。由于该地区的季节性干旱气候,高位芽蕨类较少和几种附生蕨类的附生高度也 相对较低,蕨类植物种群的数量与林下空气湿度及土壤表层的湿度一般成正相关。  相似文献   

18.
武陵山区蕨类植物研究   总被引:6,自引:0,他引:6  
吴世福 《植物研究》1998,18(3):291-303
武陵山区蕨类植物资源丰富,现知有644种(包括变种),分属116属, 46科;蕨类区系属热带-亚热带山地类型;属的地理成份有12种类型,与日本、印度-马来西亚有密切关系;武陵山区蕨类区系属我国西南区系,与华中华东区关系密切,华南、华北区次之;蕨类垂直分布分四带。  相似文献   

19.
重庆武隆天生桥是国家4A级风景名胜区,处于云贵高原大娄山褶皱带与武陵山系的过渡地带。对该区植物从科、属和种的分布区类型进行了统计分析,另外将该区区系特征与其他几个地区进行了对比分析。结果表明:①该区内有种子植物115科、475属、1292种。②大、中属共有37属,仅占总属数的7.79%,但所含种数达389种,占总种数的30.11%。说明本植物区系中优势属较为明显。③从种子植物科属分布区类型所占比例来看,该地区区系性质以热带成分占优势,其中热带分布属214属,占总属数的50.71%,这一特点与当地的环境特点是密切相关的。④区系分析表明,温带分布类型也占相当优势,有温带分布属203属,占总属数的48.10%,说明该地区区系性质具有热带到温带过渡的性质。⑤中国特有种丰富,共有881种,占总种数的68.83%。⑨经对比分析和聚类分析表明:该区与相距较远地区属的相似性系数较低,表明区系上联系较为疏远;而与邻近的几个地区属的相似性系数较高,特别与西南地区植物区系联系紧密。  相似文献   

20.
欧芷阳  杨小波 《广西植物》2008,28(3):344-351
铜鼓岭位于海南省东北部,共有维管植物166科626属984种及变种。五指山位于海南岛中部山区,共有维管植物196科911属2146种及变种。前者共有单型科54科,单种属431属,分别占科和属总数的27.11%,68.74%;后者共有单型科35科,单种属496属,分别占科及属总数17.77%,54.5%。说明五指山物种组成比铜鼓岭的更丰富,但两个区系属内种系分化程度都较弱。区系分析表明:(1)铜鼓岭以泛热带分布占优势,热带亚洲分布次之,分别占该区非世界分布属总数的34.5%和17.8%;五指山以热带亚洲分布占优势,泛热带分布次之,分别占非世界分布属总数的37.5%和24.1%;两个区系热带性质强烈,但前者以泛热带分布为主,后者以热带亚洲成分为主。(2)铜鼓岭共有35种海南特有种,占海南536个海南特有种(变种)的6.53%;五指山共有284个海南特有种,五指山特有种16种,占海南特有种的52.99%,说明其在海南植物区系中比铜鼓岭更重要。  相似文献   

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