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1.
关于浙江南部森林植物华南,华东两个区系的划分问题   总被引:9,自引:0,他引:9  
选取分布于浙江南部的116个华南森林植物区系成份的工表种。根据自然地理条件的异同,在浙江南部的温州地区和丽水地区中选择5个代表性区域,分析其与华南区系的亲缘关系,在此基础上提出本区内华南,华东两个区系的划分意见,以乐清湾的清江为起点,向东越过乐清湾至温岭县南端(坞根),再经石头桥至交陈而出东海,向西南则沿北雁荡山东南山麓地带经永嘉县南端(上塘)至青田县东端(温溪),再越过瓯江向东南拐弯至瓯海(瞿溪  相似文献   

2.
广东种子植物区系与邻近地区的关系   总被引:9,自引:0,他引:9  
廖文波  张宏达   《广西植物》1994,14(3):217-226
广东省共有种子植物约219科1434属4986种。植物区系分析和比较表明,广东种子植物区系与桂中、桂东南、湘南、赣南、闽南、闽西南、闽中植物区系最为密切,都含有丰富的华南植物区系成分,其森林区系的特征成分尤为相似,它们共同组成了华南植物区系省;另广东与海南、中南半岛北部的关系方较为密切,充分显示了北回归线地区亦即热带亚热带过渡地区植物区系的整体性特点。  相似文献   

3.
杭州湾滩浒岛种子植物区系的研究   总被引:3,自引:0,他引:3  
首次报道了我国杭州湾滩浒岛种子植物 67 科 150 属 197 种。并与纬度相近的大金山岛、佘山、天目山及浙江两个海岛进行了植物区系比较。结果表明,滩浒岛植物区系组成较复杂,地理成分多样,并以海岛植物区系丰富,广布性成分较多等为特色。滩浒岛植物区系与纬度相近的大金山岛、佘山、天目山相比,关系密切,而与不同纬度的台州海岛、温州海岛相比,则随纬度由北向南,热带植物区系成分逐步增加,温带、亚热带植物区系成分逐步减少,具有明显的纬向性。  相似文献   

4.
Phytogeographical relations of the Andean dry valleys of Bolivia   总被引:1,自引:0,他引:1  
Aim The objective of this study is to examine the phytogeographical affinities of the Andean dry valleys of Bolivia in order to contribute to a better understanding of the Andean dry flora's distribution, origin and diversity. Particular emphasis is given to the analysis of the floristic connections of this flora with more austral parts of South America. Location The dry valleys of Bolivia are located in the Andes of the southern half of the country, at elevations between 1300 and 3200 m. Methods An extensive floristic list compiled by the author to evaluate plant diversity in these Andean regions was used as the base for this study. To accomplish this, all recorded genera and species were assigned, respectively, to 11 and 12 phytogeographical elements established previously by the author. Two phytogeographical spectra were thus obtained and analysed. Results At the genus level, the Andean dry valleys of Bolivia are clearly dominated by genera that have widespread distributions (cosmoplitan and subtropical genera). Many of these reached the Andes from the lowland region of the Chaco. At species level, Andean elements constitute more than 60% of the species total, most of which are restricted to the central‐southern Andes. This suggests that Chaco‐related and Andean genera had considerable levels of speciation in these valleys. Many genera and more than half the species have their northernmost distribution in the dry valleys of Bolivia, thereby underlining strong relationships with central‐southern South America (mainly Argentina, Paraguay and southern Brazil). The data supports the belief of the existence, in central‐southern Peru, of a floristic disjunction in dry to arid environments that separates a tropical dry flora north of this limit from a dry subtropical/warm temperate flora south of it. Main conclusions The Andean dry valleys of Bolivia are diverse plant communities with high levels of endemism (c. 18% of the species). The species of this region are more related to those present in central‐southern South America than to the flora of northern South America that ranges southwards to Peru. Many of the species have restricted distributions in the dry Andes of Bolivia and Argentina, and many genera of these dry valleys have their northernmost distribution in Bolivia/southern Peru, too. The data point to high levels of speciation also in the central Andes.  相似文献   

5.
安徽齐云山区种子植物区系的研究   总被引:3,自引:0,他引:3  
据初步统计,安徽省休宁县齐云山山区共有种子植物125科,511属,867种。与邻近山地相比,种子植物的丰富程度次于黄山(134科、537属、1058种)、清凉峰(142科、547属、1083种)和牯牛降(151科、582属、1117种)。该区种子植物区系起源古老,地理成分复杂,各类热带、温带成分和中国特有成分分别占该区种子植物属总数的42.0%、54.3%和3.7%,显示该植物区系具有明显的中亚热带特性。该区系与黄山、清凉峰、牯牛降、六股尖区系的关系密切,而与天堂寨区系关系较远。  相似文献   

6.
The major characteristic of flora in Anhui are summed up in three points: 1. Since Anhui is situated in the south-east part of China, the compositions of northern and southern Chinese flora occur in this district, so it is very rich and comprehensive flora in Anhui. 2. A lot of relict species of the pre-glacial flora in this district reveal the ancientry of its origin. The author believes that the flora of Anhui is slightly influenced by geological factors, but the glaciation of Pleistocene is concerned. 3. There are many endemic genes and species which disclose the unigue habitat of this district. The flora of Anhui is close related to the adjacent provinces and the floristic regions in the country. The southern Anhui is situated in the floristic region of East China, it also shows close phylogenetical relation to the floristic regions of central, south-western and southern China. On the other hand, the northern Anhui on the upper course of Hui river belongs to the floristic region of northern China, the compositions of the local flora are in connection with the floristic regions of northern China, eastern Nei Monggol and east-northern China.  相似文献   

7.
The Zhoushan Archipelago, one of the famous fishing grounds in China, is lo cated in the northern part of the Donghai Sea, at the mouth of the Hangzhou Bay (Fig. 1). The flora of the archipelago was botanically little known. After 1972, several botanical ex plorations to the archipelago were conducted by Qiu L.-Q. of the Shanghai Museum of Natu ral History, and nearly one thousand numbers of plant specimens were collected. From these specimens, we have identified about 500 species of seed plants. The present paper deals with a numerical taxonomic study of the floristic affinities of seed plants of the Zhoushan Archipelago by means of both cluster and principal component analyses (PCA). The total distribution realm of the Zhoushan floristic elements is divided into 18 regions, which were used as Operational Taxonomic Units (OTU). The 348 native species and infrasp ecific taxa (see Appendix 1, excluding cultivated plants, ruderals and exotics) of seed plants were used as characters of the OTUs, A normal cluster analysis using UPGMA gave rise to phenogram (Fig. 1). The phenogram provides a great amount of information regarding the floristic affinities between Zhoushan and the other regions. In the PCA, method of inverse analysis was used and has brought forth two diagrams of dimensional program (Fig. 2a,b). These diagrams give some hints of the distributional trends of geographical elements and floristic affinities. The result of the above analyses shows that the floristics of the Zhoushan Archipelago is the most closely related to those of its neibouring regions, for instance, Zhejiang mainland, Jiangsu and some other regions of eastern China. Though rich in island elements, the archipelago has almost no endemic species. The short distance between the archipelago and the mainland, which has favored mutual exchange of plants, and the severe destruction of the original forest vegetation, may account for this phenomenon. The floristic similarities between Zhoushan and Taiwan of China and between the archipelago and Japan are not so remarkable. This may be due to both the climatical difference and geographical barriers existing between these floristic regions. Yet the presence of a number of linking plants confined to these floras, such as Rhaphiolepis integerrima, Anodendron salicifolium, and Eurya japonica, etc., suggests that these regions should be considered as being of the common tertiary origin. The mountain forest flora of Zhoushan is more closely related to those of southern regions than to those of northern regions of China, From the point of view of floristic regionalization, it is appropriate to consider the flora of the Zhoushan Archipelago as a part of the northern subregion of the mid-subtropical region.  相似文献   

8.
The Greater Cape Floristic Region   总被引:3,自引:0,他引:3  
Aim The Cape Floristic Region (CFR) (Cape Floristic Kingdom) is currently narrowly delimited to include only the relatively mesic Cape fold mountains and adjacent intermontane valleys and coastal plains. We evaluate the floristic support for expanding the delimitation to include the whole winter‐rainfall area (arid and mesic climates) into a Greater CFR. Location Southern Africa, particularly the south‐western tip. Methods The initial divisive hierarchical classification analysis twinspan used the presence/absence of vascular plant genera to obtain major floristic groupings in southern Africa. For the more detailed analyses, we scored the flora as present/absent within a set of centres, among which the floristic relationships were investigated (agglomerative methods, upgma and minimum spanning trees). These analyses were conducted with species, genera and families separately. The centres were grouped into five regions. The species richness and endemism was calculated for the centres, regions and combination of regions. The dominant floristic components of each region were sought by calculating the percentage contribution of each family to the flora. Results The divisive method showed that the winter‐rainfall areas are floristically distinct from the rest of southern Africa. The species‐ and generic‐level analyses revealed five regions: CFR, Karoo Region, Hantam‐Tanqua‐Roggeveld Region, Namaqualand Region and Namib‐Desert Region. The CFR has the highest endemism and richness. However, the combination of the CFR, the Hantam‐Tanqua‐Roggeveld Region and the Namaqualand Region results in a higher total endemism. Combined, these three regions almost match the region delimited by the twinspan analysis, and together constitute the Greater CFR. Main conclusions The CFR constitutes a valid floristic region. This is evident from the endemism and the distinctive composition of the flora. However, the total endemism is higher for the whole winter‐rainfall area, and this supports the recognition of the larger unit. If floristic regions are to be delimited only on endemism, then the Greater CFR is to be preferred. If floristic regions are delimited on the composition of their floras at family level, then the support for such a grouping is weaker.  相似文献   

9.
The flora of the White Carpathians, a mountain range in the south-east of the Czech Republic, is documented by about 485,000 records of vascular plant occurrences collected since the mid-19th century. A total of 1299 species recorded in 93 grid cells of 2.8 × 3.1 km were used for an analysis of spatial patterns of floristic diversity in the White Carpathians. Multivariate statistical techniques such as ordination and classification were used to reveal the main gradients in floristic composition and species richness, and measured environmental data and Ellenberg indicator values were used to assess underlying environmental factors. There is a striking floristic contrast between the western and eastern part of the study area, which is associated with differences in climate, mean altitude, topographic heterogeneity measured as altitudinal range, and land use. The western part is characterised by thermophilous, continental and calcicolous species of open habitats. In contrast, the more forested eastern part along the state border with Slovakia and the north-eastern part of the area are characterised by acidophilous species with higher moisture requirements. This pattern is consistent with the established phytogeographical division of the Czech Republic into the phytogeographical regions of Thermophyticum and Mesophyticum. The further division of the area into four regions, based on classified grid data, is also similar to the current division into phytogeographical districts, except for the Javorníky district. There are two distinct hot spots of species richness, in the western and the extreme north-eastern part. A poorer flora was found in landscapes with intensive agriculture. Species richness is associated with different environmental factors than species composition, namely with soil types and land-use categories. Alien species are more common in areas with a higher incidence of arable land and built-up areas, and less common in areas dominated by grasslands and forests.  相似文献   

10.
南海岛屿种子植物区系地理的研究   总被引:15,自引:2,他引:13  
本文通过实地考察,广泛收集前人的研究资料,概述了南海岛屿地区的自然条件和植被,对南海岛屿种子植物的区系组成、特点、分布区类型、特有现象和替代现象等进行了较详细的分析,并与邻近植物区系进行了比较研究。同时,根据区内植物分布的特点和自然条件特征划分为5个植物区系小区,最后对南海岛屿地区植物区系的起源与演化进行了讨论。  相似文献   

11.
Diversity and biogeography of the Antarctic flora   总被引:1,自引:0,他引:1  
Aim To establish how well the terrestrial flora of the Antarctic has been sampled, how well the flora is known, and to determine the major patterns in diversity and biogeography. Location Antarctica south of 60° S, together with the South Sandwich Islands, but excluding South Georgia, Bouvetøya and the periantarctic islands. Methods Plant occurrence data were collated from herbarium specimens and literature records, and assembled into the Antarctic Plant Database. Distributional patterns were analysed using a geographic information system. Biogeographical patterns were determined with a variety of multivariate statistics. Results Plants have been recorded from throughout the Antarctic, including all latitudes between 60° S and 86° S. Species richness declines with latitude along the Antarctic Peninsula, but there was no evidence for a similar cline in Victoria Land and the Transantarctic mountains. Multi‐dimensional scaling ordinations showed that the species compositions of the South Orkney, South Shetland Islands and the north‐western Antarctic Peninsula are very similar to each other, as are the floras of different regions in continental Antarctica. They also suggest, however, that the eastern Antarctic Peninsula flora is more similar to the flora of the southern Antarctic Peninsula than to the continental flora (with which it has traditionally been linked). The South Sandwich Islands have a flora that is very dissimilar to that in all Antarctic regions, probably because of their isolation and volcanic nature. Main conclusions The Antarctic flora has been reasonably well sampled, but certain areas require further floristic surveys. Available data do, however, allow for a number of robust conclusions. A diversity gradient exists along the Antarctic Peninsula, with fewer species (but not fewer higher taxa) at higher latitudes. Multi‐dimensional scaling ordination suggests three major floral provinces within Antarctica: northern maritime, southern maritime, and continental. Patterns of endemism suggest that a proportion of the lichen flora may have an ancient vicariant distribution, while most bryophytes are more recent colonists.  相似文献   

12.
Right whales off Namibia were severely depleted by early 19th century whaling, and rarely featured in modern whaling catches in the 1920s. Aerial surveys of the Namibian coastline from 1978 and onwards revealed increasing numbers of right whales, but few cow‐calf pairs. Aerial surveys off South Africa since 2009 showed a major decline in the availability of animals without calves. Twenty individual matches were made between 94 whales photographed off Namibia/Northern Cape in 2003–2012 and 1,677 photographed off South Africa in 1979–2012. Eight were adult females that calved in South African waters, but only one was also seen with a calf off Namibia. Twelve out of 13 individuals off Namibia with distinctive dorsal pigmentation were first seen as calves off South Africa. These results strongly indicate connectivity between the two regions, while the presence off Namibia of three adult females from the South African population in the season in which they are believed to conceive suggests that there is unlikely to be any genetic differentiation between the two areas. We conclude that the reappearance of right whales off Namibia represents range expansion from South Africa rather than the survival of a few remnants of an originally separate stock.  相似文献   

13.
鹞落坪国家级自然保护区植被类型的初步探讨   总被引:7,自引:0,他引:7  
提供安徽省鹞落坪国家级自然保护区植被类型的初步概况与与比较分析。在世界植被区划上,该区属泛北极植物区,中国--日本森林植物亚区的华东区,是华中、华西、华北、华南植物区系与华东植物的渗透、过渡和交汇地带,故植物物种类丰富复杂。今经实地考察,并通过对所得的有关数据资料的整理与统计,采用相似性系数分析方法,对该保护区植被组成进行了初步的探讨,认为:该区计有野生种子植物134科,590属,1428种(含种下等级);该区森林生态系统结构完整,植物群落分为8个植被型(亚型)和35个群系组。主要有针叶林、针阔叶混交林、竹林、灌丛、草甸等,此外还有沼泽和水生植被。  相似文献   

14.
Abstract

Mount Medvednica (northwestern Croatia), mostly consisting of slates and marls, rises to the north, above the Croatian capital of Zagreb, from 300 to 1,035 m a.s.l. A floristic research was carried out in the area of Medvednica Nature Park, which consists mainly of the western part of the mountain. On the whole, 1,352 taxa of vascular plants were recorded from all sources (field observations, literature and herbaria). Out of these, 48 taxa are strictly protected, 228 are protected, 67 taxa are considered threatened according to the IUCN categories, and 9 taxa are endemic for the Croatian flora. The life-form analysis of the investigated flora shows the predominance of hemicryptophytes, followed by therophytes and geophytes, while the chorological analysis has evidenced the prevalence of Euro-Asiatic, South European and cosmopolite geographical groups. The biological/chorological cross-spectrum was laid out by considering the percent of every life-form for each geographical element. In order to evaluate the floristic richness of the studied area, the α-index was calculated and then compared with the α-indices of similar regions in Croatia and several European countries. A floristic diversity map of Medvednica Nature Park is presented here for the first time.  相似文献   

15.
乌鲁木齐河上游大西沟地区种子植物区系特征分析   总被引:5,自引:0,他引:5  
本文研究了乌鲁木齐河上游大西沟地区的种子植物区系特征。调查表明,该地区现有种子植物406种,隶属198属, 46科。种子植物科的组成以世界分布型科为主;属的组成以北温带分布型为主;种的组成以温带亚洲分布为主。区系成分的分析结果说明,该地区植物区系是东天山植物区系的组成部分,具有典型的北温带植物区系特征。该地区植物区系具有山地植物区系和垂直变化的特点,大部分种类集中分布于山地中部。与周围地区的共有程度分析表明,尽管东亚分布型在植物区系组成中占有的份额很小,但是在植物区系的形成和起源上,与我国北方森林和草原区系有很大的历史渊源性,明显不同于中亚荒漠植物区系。  相似文献   

16.
广州市流溪河森林公园植物区系的初步研究   总被引:8,自引:0,他引:8  
本文从植物区系地理学的角度,讨论了流溪河森林公园植物区系的基本特征、科属地理成分、与邻近植物区系的联系.以及在中国植物区系研究中的作用.本区系位于泛北极植物区、中国-日本森林植物亚区、华南地区。初步分析结果表明,该区系的热带、亚热带成分占有明显的优势,并具有向古热带印度-马来西亚植物区系过渡的特点.本区系和鼎湖山、黑石顶区系联系密切.具有相似的典型南亚热带区系成分.研究流溪河植物区系的组成和特点.对于进一步研究华夏植物区系以及我国植物区系和其它植物区系的联系.均有一定的意义。  相似文献   

17.
Research into Plant Invasions in a Crossroads Region: History and Focus   总被引:1,自引:0,他引:1  
The Czech Republic is a central European country whose geographical location, natural conditions, history of human settlement, and present land-use management make it relatively prone to plant invasions, hence it represents a convenient model for their study. Research in plant invasions, which date to the late 19th century, is reviewed in the present paper. A long-term floristic tradition allowed for the accumulation of a large body of floristic data on alien plants. During the 1960s–1970s, the main research focus was on their distribution. In this period, attempts were also made to predict potential invasiveness of weeds of arable land. The success rate of this prediction was about 39%. Considerable effort was put into a detailed classification of human-accompanying plants and the terminology associated with the issue. There is a high level of taxonomic research conducted in the country, and the new Flora of the Czech Republic treats the immigration status of taxa with reasonable care and detail. A complete, serious catalogue of the alien plants of the country has been published recently: there are currently 1378 alien plants (33.4% of the total flora). The core of present research in plant invasions is in ecological, biological, and biogeographical studies, focussed on (i) the history of invasion of particular species since their introduction, (ii) the role and importance of alien species in vegetation, including their participation in succession, and (iii) the major invasive species of the Czech flora and comparison of congeners. Reynoutria spp., Heracleum mantegazzianum, Oenothera spp., Pinus strobus, and Bidens frondosa are among the taxa most intensively studied in recent time. A complete list of 69 invasive plants in the Czech flora introduced after the year 1500 [following the definition of Richardson et al. (2000a) Diversity and Distributions 6: 93–107] is given. The available legal instruments relevant to the issue are reviewed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
安徽省清凉峰自然保护区植物区系的研究   总被引:18,自引:2,他引:16  
清凉峰自然保护区有维管束植物181科,601属,1228种,是安徽植物资源集中地之一。区系成分起源古老,孑遗种多,保存着丰富的珍稀、濒危植物。种子植物区系地理成分复杂,各类热带成分、温带成分、中国特有成分分别占本区种子植物属总数的33.6%、62.96%、3.44%,显示了本区植物区系的亚热带特性。本区植物区系97.6%的成分与华东植物区系共有,且含华东特有种111种,具有典型华东植物区系特征。本区植物区系与西天目山、黄山植物区系关系最密切,其次为大别山和庐山,再次为神农架。  相似文献   

19.
山东省蕨类植物的区系分析   总被引:16,自引:0,他引:16  
对山东省蕨类植物区系成分、地理分布和生态特点进行了初步研究,并与辽宁、日本等6个地区进行了比较。结果表明,山东省蕨类植物区系具有以下几个特点:1.区系成分不算丰富,但地理成分多样,以温带成分占优势,也残存有较多的热带成分;2.种系分化强烈,特有现象明显,特有种占11.3%;3.地理分布极不均匀,并存在明显的地带性差异,表现为由南向北、由东向西种类减少;4.与辽宁、北京、河南关系密切,与秦岭、日本也  相似文献   

20.
Neotropical aquatic ecosystems have a rich aquatic flora. In this report, we have listed the aquatic flora of various habitats of the upper Paraná River floodplain by compiling data from literature and records of our own continuous collections conducted during the period 2007-2009. Our main purposes were to assess the macrophyte richness in the Paraná floodplain, to compare it with other South American wetlands and to assess whether the number of species recorded in South American inventories has already reached an asymptote. We recorded a total of 153 species of macrophytes in the Upper Paraná River floodplain, belonging to 100 genera and 47 families. In our comparative analysis, a clear floristic split from other South American wetlands was shown, except for the Pantanal, which is the closest wetland to the Paraná floodplain and, therefore, could be considered a floristic extension of the Pantanal. The species accumulation curve provides evidence that sampling efforts should be reinforced in order to compile a macrophyte flora census for South America. The high dissimilarity among South American wetlands, together with the lack of an asymptote in our species accumulation curve, indicates that the sampling effort needs to be increased to account for the actual species richness of macrophytes in this region.  相似文献   

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