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Theoretical basis of ecologo-floristic classification according to Braun-Blanquet approach is discussed with the special attention to the contribution of Russian scientists. Principal results concern presentation of vegetation continuum in discrete classification units: polymodal conception of plant communities, principle of plural syntaxonomic decisions, pragmatic approach to classification, method of homological rows of plant communities, etc. Current ecologo-floristic classification of vegetation in Russia consists of 77 classes. This system is a good basement for estimation of rarity of plant communities and biodiversity protection. The first variant of "Red Book" of plant communities of Russia and other eastern European countries is discussed.  相似文献   

3.
This paper describes the vegetation of the Carson Desert (Nevada, USA) based on a phytosociological analysis of its major plant associations, as determined by the Braun-Blanquet method. Diagnostic tables, climatic, edaphic, and biogeographical data were used to establish floristic affinities among identified plant communities and to interpret their distributions in zonal gradients. Their syntaxonomic positions in the classes Allenrolfeetea occidentalis and Artemisio tridentatae–Juniperetea osteospermae, and in the new class Sarcobatetea vermiculati were also established. Three associations (Atriplici confertifoliae–Sarcobatetum baileyi, Atriplici canescentis–Psorothamnetum polydenii, and Suaedo moquinii–Sarcobatetum vermiculati) are described here for the first time along with the order Sarcobatetalia vermiculati and the alliance Sarcobation vermiculati.  相似文献   

4.
在法瑞学派样地调查法的基础上,采用双向指示种分析(TWINSPAN)和趋势对应分析(DCA)对大山包黑颈鹤自然保护区草甸植被进行数量分类和排序研究。调查样地包含114个物种,分属31科72属,其中禾本科(14种)、菊科(13种)、蓼科(8种)、石竹科(6种)、玄参科(6种)等科所含物种较多。经TWINSPAN分类,106个样地分为20个聚组,根据其指示种确定为20个群丛。样地DCA和物种DCA排序结果反映了植物群丛与指示种之间的一致关系,排序轴的生态学意义说明水分和海拔两个环境因子同时影响该区草甸植被的分布。  相似文献   

5.
The vegetation gradient analysis along two complex gradients (height above low water level and soil-salinity) has been carried out, and a floristic classification of communities drawn up following the principles of the Braun-Blanquet approach. A new classGlycyrrhizetea glabrae has been established. The remaining communities are classified underMolinio-Arrhenatheretea, Phragmitetea, Bolboschoenetea maritimi andCrypsietea aculeatae. General regularities of variations in vegetation along the flood-plain longitudinal profile are discussed, phytocoenological tables describing the syntaxa established are given.  相似文献   

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Abstract. The launching of international phytosociological projects requires a re-evaluation of vegetation units (syntaxa) of different phytosociological schools and their integration into one global classification system. Despite many difficulties, this possibility is offered by the floristic-phytosociological system - a hierarchical system of syntaxa defined by floristic-socio-logical criteria. Associations (and lower syntaxa) of the Zürich-Montpellier School as well as associations (later called sociations) of the Uppsala School are defined by means of the floristic composition of plant communities and fit this postulate; their syntaxonomic identity can be checked by tabular comparison of vegetation relevés. Not only the presence of diagnostic species but also the specific combination of sociological groups of species, dominance of species or even the absence of certain species or species groups can be used as syntaxonomic criteria. The syntaxonomic identification of an association of the Uppsala School with one of the Zürich-Montpellier School means uniting syntaxa of the same rank in the sense of the Code of Phytosociological Nomenclature. If a sociation is found to fit the criteria of an association delimited by the Zürich-Montpellier methods, the rank of an association can be attributed to this sociation and its name can thus be validated in the sense of the Code.  相似文献   

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Zusammenfassung In der vorgelegten Arbeit wurde die sogenante deduktive Klassifikationsmethode der anthropogenen Pflanzengesellschaften behandelt. Diese Methode geht vom System der höheren Vegetationseinheiten der Braun-Blanquet Schule aus. Sie ermöglicht die syntaxonomische Bearbeitung zahlreicher anthropogener Gesellschaften unserer Kulturlandschaft, die nur aus Arten mit breiterer ökologischer und zönologischer Amplitude zusammengesetzt sind, und zwar ohne unerwünschte Verwechslung der Bestimmungsmerkmale einzelner Rangstufen des Systems (Klassen-, Ordnungs-, Verbands- und Assoziationskenn-und trennarten). Die Grundprinzipien der Methode wurden schon früher von Kopecký & Hejný (1971, 1973, 1974) und Kopecký (1976) erläutert. Die vorliegende Arbeit bringt eine präzisierte Auslegung der Methode auf Grund neuer Erfahrungen, die bei der Bearbeitung der spontan entstandenen strassenbegleitenden Gesellschaften derMolinio-Arrhenatheretea Tx. 1937 in Nordostböhmen gewonnen wurden. Aus dem reichen Aufnahmematerial werden nur einige Aufnahmen der Basalgesellschaften mitAlopecurus pratensis und der von ihnen abgeleiteten Derivatgesellschaften mitDactylis glomerata undAgropyron repens fur die anschauliche Demonstration der Methode beigegeben (Tab. 1 und 2). Die Aufnahmen der übrigen Gesellschafts-typen werden in einer anderen Arbeit (Kopecký 1978) veröffentlicht.
Summary Use of a so-called deductive method in syntaxonomic classification of roadside plant communities in NE Bohemia.The present paper explains the so-called deductive method of syntaxonomic classification of plant communities, derived from the system of syntaxa of higher rank of the Braun-Blanquet approach. This method enables the synthesis of vegetations units of the varied anthropogenic plant communities in the man-made landscape, and their arrangement within the existing system, without changing the classification and determination criteria of both the higher and lower syntaxa in this system. Basic principles of this method have been outlined earlier by Kopecký & Hejný (1971, 1973, 1974) and Kopecký (1976). Following the newly obtained data and experience, this paper brings further details and more precise explanation of the method. Recently, the deductive method has been applied to the classification of turf communities which spontaneously develop along the roads in NE Bohemia. In order to illustrate the principles of the method, selected relevés of basal communities withAlopecurus pratensis (Table 1), and respective communities derived from these basal communities (Table 2) are presented. A complete set of vegetation relevés of all other roadside communities will be published elsewhere (Kopecký 1978).
Die wissenschaftlichen Pflanzennamen sind nach Rothmaler et al. (1966) angeführt.  相似文献   

10.
The Pinus halepensis Mill. forest vegetation of the central-eastern European Mediterranean basin (France, Italy, Croatia, Albania, Greece) is described here. This study was carried out considering published and unpublished phytosociological data, with the organisation of a systematic classification (syntaxonomic scheme) of the order Pinetalia halepensis according to the principal floristic variations, at multiple spatial scales and according to the physiognomic–structural, floristic, ecological and biogeographical characteristics. Five alliances and 25 associations are recognised.  相似文献   

11.
中国常绿阔叶林分类试行方案   总被引:15,自引:0,他引:15       下载免费PDF全文
植被分类是植被生态学研究中最复杂、充满着争论的问题之一,直到现在并没有一个能为植被学家共同接受的、统一的分类系统。常绿阔叶林的复杂性仅次于热带雨林,加之在人类长期干扰下,变化极大,过渡性群落极多,更增加了分类的困难。中国常绿阔叶林分类经历了漫长的道路,20世纪50年代学习苏俄学派,60年代初引进威斯康星学派的“重要值"概念,在研究云南滇青冈(Cyclobalanopsis glaucoides)林时也曾试用过法瑞学派的理论和方法。80年代《中国植被》(1980)一书的作者们提出,对于“南方某些类型"在“群系(Formation)"和“群丛(Association)"划分时应采用“标志种(Diagnostic species)"的原则,当时由于资料所限,这一原则并未得到贯彻。本文在总结以往分类方案的基础上,根据高级单位以生态外貌、中级单位以优势度类型、低级单位以特征种组的分类原则,构建了从“群丛"、“群系"、“群系组"到“植被亚型"和“植被型"的中国常绿阔叶林分类系统。将中国常绿阔叶林划分出3个植被型、8个植被亚型、14个群系组和53个群系。这些群系大都占据一定的地理区域,并与一定的生境相联系。  相似文献   

12.
网格化清查方法有助于准确诊断一个地区的植被性质,并为探索植被分类方法提供支持。该研究以上海大金山岛为对象,借助航拍影像等间距地将其划分为140个清查网格(40 m × 40 m),按照统计样方法逐网格调查植物群落特征,综合运用列表法和双向指示种法,进行植被分类并绘制现状植被图。按照新修订的植被三级分类系统进行分类:一级单位根据植被型,大金山岛植被划分为落叶阔叶林、常绿落叶阔叶混交林、常绿阔叶林、落叶阔叶灌丛、常绿落叶阔叶混交灌丛、常绿阔叶灌丛和草丛; 二级单位根据优势种和植物区系特征,可划分出15种群丛或群落类型; 三级单位根据群落年龄和外貌可划分为22种群落类型。以上结果表明,大金山岛不仅是上海市物种多样性最高的区域,也拥有华东海岛最典型、最多样的自然半自然森林群落。就植被状态而言,地带性森林群落处于演替中后期,但少数次生植被处于演替前期,且面临着猴群干扰导致的植被发育停滞不前等生态问题。关于植被分类方法,网格化清查方法可充分揭示植物群丛连续性中包含间断性和过渡性群落的现象。  相似文献   

13.
The vegetation classification in China was updated by referring to recent advances for vegetation classification worldwide and on the basis of our former paper Recognition and Proposal on the Vegetation Classification System of China (hereafter, "Recognition and Proposal"). In this revision, the criteria for vegetation classification were discussed and unified, and a quantified standard for high, medium, and low level units in a new hierarchical classification scheme was supplemented. Compared with the old classification scheme in "Recognition and Proposal", the units at the level of vegetation type were substantially changed. Finally, in order to improve mutual communication among international peers, a comparison was carried out between the new revised scheme and each of International Classification and Mapping of Vegetation of UNESCO, The National Vegetation Classification Standard of United States, and The Braun-Blanquet Classification Scheme.  相似文献   

14.
In this study we examine the relationships between the vegetation of beech and beech-oak forest communities (Hordelymo-Fagetum, Galio-Fagetum, Deschampsio-Fagetum, Betulo-Quercetum) and their soil conditions in the lowlands of northern Germany, based on 84 sample plots. In all plots the vegetation was recorded and soil parameters were analysed (thickness of the O- and the A-horizons, pH, S-value, base saturation, C/N, mean Ellenberg moisture indicator value). The vegetation classification according to the traditional Braun-Blanquet approach was compared with the result of a multivariate cluster analysis. Vegetation-site relationships were analysed by means of an indirect gradient analysis (DCA).Both traditional classification methods and the cluster analysis have produced comparable classification results. So far as the species composition is concerned, a similar grouping of sample plots was found in both approaches. Multivariate cluster analysis thus supports the classification found by the Braun-Blanquet method. The result of the DCA shows that the four forest communities mentioned above represent clearly definable ecological units. The main site factor influencing changes in the species composition is a base gradient, which is best expressed by the S-value. In addition, within the series Hordelymo-Fagetum - Galio-Fagetum - Deschampsio-Fagetum the C/N-ratios and the thickness of the organic layers (O-horizon) increase continuously. By contrast, the floristic differences between oligotrophic forest communities (i.e., Deschampsio-Fagetum and Betulo-Quercetum) cannot be explained by a base gradient and increasing C/N-ratios. It is suggested that a different forest management history in some cases (e.g., promotion of Quercus robur by silvicultural treatments) is responsible for differences in the species composition, but on the other hand the result of the DCA indicates that Fagus sylvatica is replaced by Quercus robur with increasing soil moisture (i.e., with the increasing influence of a high groundwater table). Summarizing these results, it can be concluded that the ecological importance of single site factors affecting the species composition changes within the entire site spectrum covered by the beech and beech-oak forests of northern Germany.  相似文献   

15.
Aim of the research was the recognition of ecological species groups in beech forests south of the Caspian Sea (Northern Iran) and the determination of the main effective environmental factors explaining the distribution of plant ecological groups. Selective stratification sampling was used to locate samples. A total of 120 samples (400 m2 each) were selected in Fagetum communities within the study area. At each sample, a floristic list of the plot and an estimate of percent cover and abundance of all vascular plants were recorded in separate strata using the Braun-Blanquet scale. At the center of each vegetation plot, two soil samples were taken of 0–10 and 10–30 cm depth levels for physico-chemical analyses. Cluster analysis was used for the classification of vegetation samples and Multi-response Permutation Procedure (MRPP) was used to test the hypothesis of no difference between ecological groups in the species space. Indicator species analysis was used to identify indicator species for each group. A Tukey test was used to compare environmental variables among groups. Detrended Correspondence Analysis (DCA) was used to analyze the relationships between the ecological groups and environmental variables.  相似文献   

16.
《植物生态学报》2017,41(2):269
The vegetation classification in China was updated by referring to recent advances for vegetation classification worldwide and on the basis of our former paper Recognition and Proposal on the Vegetation Classification System of China (hereafter, “Recognition and Proposal”). In this revision, the criteria for vegetation classification were discussed and unified, and a quantified standard for high, medium, and low level units in a new hierarchical classification scheme was supplemented. Compared with the old classification scheme in “Recognition and Proposal”, the units at the level of vegetation type were substantially changed. Finally, in order to improve mutual communication among international peers, a comparison was carried out between the new revised scheme and each of International Classification and Mapping of Vegetation of UNESCO, The National Vegetation Classification Standard of United States, and The Braun-Blanquet Classification Scheme.  相似文献   

17.
Abstract. A numerical classification method and the Braun-Blanquet method, based on external criteria, were compared with the aim of clarifying the differences in predictive power. The numerical analysis leads to a changed perspective on the floristic data and produces, as a whole, an ecologically more differentiated classification. The groups produced by numerical analysis are almost identical with the Braun-Blanquet classification with respect to marginal site conditions but they may differ in cases of intermediate site conditions. Nevertheless, a classification emerges which is on the whole, both floristically and as to site, very similar to the Braun-Blanquet classification. The discriminatory importance of the external variables is, to a large extent, the same in both methods, but discriminant analysis shows that the numerical classification is somewhat more predictive.  相似文献   

18.
Classification of vegetation: Past,present and future   总被引:1,自引:0,他引:1  
Abstract. This paper is a report on the past, status-quo and perspectives of vegetation classification, still a major occupation of many vegetation scientists. The history of vegetation classification is discussed against a background of several controversial issues such as the problem of continuum vs. discontinuum, naturalness vs. arbitrariness of the nature of plant communities, universality vs. ad hoc character of syntaxonomic schemes, as well as classical versus numerical approaches to data analysis for classification purposes. The development of the methodology of vegetation science and the present image of vegetation classification is documented by a bibliometric analysis of the publication record of four majorjournals: Journal of Vegetation Science, Vegetatio, Phytocoenologia and Tuexenia. This analysis revealed a persisting controversy between traditional and numerical approaches to vegetation classification. A series of important changes in vegetation science (foundation of new journals, change of editorial policy by the established, important meetings) punctuate a period called the ‘Innovation period’. Several trends in the development of methods of vegetation systematics are summarized under the headings formalism, pluralism, functionalism, pragmatism and indeterminism. Some new features, such as the development and improvement of numerical tools, use of large data banks and attempts to summarize the theory of vegetation classification are discussed. The new growth-form system of Barkman initiated a revival of physiognomy-based vegetation classification. Within this framework the use of the character-type concept and the development of new numerical methods for studying the hierarchical structure of character-set types seems to be a promising approach. The achievements of population biology and ecophysiology have affected vegetation science by emphasizing the functionality of species within plant communities. The use of guilds and other functional groups has experienced an increasing interest from vegetation scientists. Applied in vegetation science, fuzzy-set theory has bridged the techniques of classification and ordination of plant communities.  相似文献   

19.
Wetlands occur where biotic and abiotic conditions combine to create unique habitats and plant assemblages. These systems have anaerobic or hydric soil resulting from waterlogging and are found across all nine biomes in South Africa. Wetlands can thus be regarded as hosting azonal vegetation. On Platberg, the freshwater wetlands are embedded within the Grassland Biome forming distinct units. Platberg wetlands were surveyed and described to explain and document vegetation of this inselberg. Additional aims were to elucidate Afro-montane floristic links with the Drakensberg Alpine Centre, and provide data for conservation management. The study site is located in the Eastern Free State, South Africa, on edge of the Great Escarpment. It is one of an archipelago of more than 20 inselbergs stretching north from the Drakensberg. A total of 51 sample plots (30 m2) were located in a randomly stratified manner within the wetland units to include all variations in the vegetation. The data was analysed using the TWINSPAN classification algorithm, refined by Braun-Blanquet procedures. The analysis showed the wetlands divided into five communities, six sub-communities and six variants. The wetland communities had an average of 13.56 species per relevé, ranging from 7 to 29 species per sample plot. Numerous floristic links with the Drakensberg Alpine Centre, the Cape Floristic Region and the Grassland biome were found. Platberg shows vegetation and hydrogeological affinity with low altitude freshwater and the high altitude Lesotho Mires of the Drakensberg Alpine Centre. A list of high altitude wetland species was compiled.  相似文献   

20.

Questions

What are the syntaxonomic and synchorological patterns of the xerothermic chasmophytic vegetation in the central part of the Mediterranean Basin? What are the diagnostic species of the high‐rank syntaxa of Asplenietalia glandulosi, Onosmetalia frutescentis and Centaureo dalmaticae‐Campanuletalia pyramidalis?

Location

Mediterranean coastal and subcoastal areas of southern France, Italy, Malta, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Albania and of mainland Greece.

Methods

The data set of 1,261 published relevés was analysed using hierarchical clustering (Flexible Beta method), involving a series of data transformations. Indicator species analysis was used to select the best dendrogram solution and identify diagnostic taxa of the main clusters. The dendrogram was interpreted from a syntaxonomic point of view, using nomenclatural type relevés as a basis. The NMDS ordination was performed in order to visualize the floristic relationships among associations and high‐rank syntaxa. MRPP was used to test for differences among alliances.

Results

The classification revealed four main clusters of relevés representing the chasmophytic vegetation of southern France, Sardinia and the northwestern part of Italy (Asplenienalia glandulosi/Asplenietalia glandulosi), the southwestern part of Italy and Malta (Tinguarrenalia siculae/Asplenietalia glandulosi), the Adriatic Basin area (Centaureo dalmaticae‐Campanuletalia pyramidalis) and the southern Balkans (Onosmetalia frutescentis). The NMDS ordination confirmed the overall pattern, while MRPP showed significant differences among the alliances of the above‐mentioned orders and suborders. The lists of diagnostic taxa of the high‐rank syntaxa were revised according to a supra‐national perspective.

Conclusions

The new syntaxonomic scheme provides a comprehensive overview of the chasmophytic vegetation of the central part of the Mediterranean Basin. This scheme mostly matches the recently published EuroVegChecklist, but also exhibits important novelties concerning the syntaxonomic position of some alliances (Dianthion rupicolae, Centaureion pentadactyli, Arenarion bertolonii and Caro‐Aurinion), and the floristic and chorological relationships among high‐rank syntaxa, with new revised sets of diagnostic taxa. This revision might be useful for further small‐scale phytosociological studies.
  相似文献   

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