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1.
Plant communities dominated by Phragmites japonica and described as Phragmitetum japonicae Minamikawa 1963 were studied in northern part of the Korean Peninsula. 40 sampled relevés were compared with similar vegetation in South Korea and Japan. In total 118 phytocoenological relevés were synthesized. Three subassociations (artemisietosum feddei, boehmerietosum spicatae and inops) were described as new. Two subassociations (humuletosum scandentis and polygonetosum thunbergii) described from Japan were found also in Korea. The problems of classification of this heterogeneous and species-poor vegetation unit were discussed.  相似文献   

2.
Phytosociological characteristics and a rate of endangerment of the salt marsh vegetation in central and southern parts of the east Adriatic coast were studied. A total of 73 vegetation relevés were made and elaborated according to the standard procedures of the Braun-Blanquet method. Numerical analysis of the relevés and life forms was performed. Two associations of the class Arthrocnemetea-Puccinellio festuciformis-Arthrocnemetum fruticosi and Limonio-Artemisietum coerulescentis were recorded, together with the association Juncetum maritimo-acuti of the class Juncetea maritimi. These associations show no significant differentiation with regard to their floristic composition, but only in terms of particular species cover and frequency rates, as well as by life forms and microecological habitat conditions. These are specific habitats, rarely found in the studied area, and highly threatened by human activity (tourism, agriculture).  相似文献   

3.
Zvjezdana Stančić 《Biologia》2008,63(6):1089-1103
In this paper, 450 relevés of grassland vegetation of the Molinio-Arrhenatheretea class in northwest Croatia have been classified using the agglomerative Ward’s Method in the PC-ORD program. In the process of classification, the following seven groups were obtained: 1. Bromus erectus-Arrhenatherum elatius, 2. Arrhenatherum elatius, 3. Crepis biennis-Arrhenatherum elatius, 4. Luzula campestris-Holcus lanatus, 5. Deschampsia cespitosa-Betonica officinalis, 6. Equisetum palustre, 7. Oenanthe silaifolia-Alopecurus pratensis. The results of the classification for the most part correspond to the traditional syntaxonomic system. The plant communities with the largest number of relevés in the data set are the association Arrhenatheretum elatioris “typicum” (group 2) and the association Holcetum lanati (group 4). They represent the most anthropogenically influenced grasslands of the study area. In the analysis of the ecological factors by PCA in the CANOCO program it is established that separation of the relevés is influenced most greatly by moisture, followed by humus, temperature, light and soil reaction. From the standpoint of nature conservation, the wet meadows of the Molinietalia order are the most valuable, because of the notable diversity of species and communities, as well as a considerable number of threatened plant species.  相似文献   

4.
Nine vegetation types were distinguished using cluster analysis within Molinion meadows in Slovakia. Vegetation of cluster 1 occurs on most acidic soils and is characterized by the occurrence of species of the Caricion fuscae alliance and of the Nardus grasslands. Vegetation of cluster 2 is also found on rather acidic soils but in contrast to cluster 1 vegetation it contains species of base-rich sites, such as Betonica officinalis, Galium boreale or Serratula tinctoria. Vegetation of cluster 3 occurs in wet base-rich habitats and often contains species of the Caricion davallianae alliance. Species of dry and Nardus grasslands are typical for vegetation of cluster 4, which is found at the driest sites and is confined to oligotrophic sandy soils. Vegetation of clusters 5 and 6 occurs on moist mesotrophic soils. Their species composition is quite similar, the main difference being that the former includes species-poor relevés and the latter includes species-rich relevés. Relevés of cluster 7 include species of dry grasslands and some ruderal species and represent degraded types of inundated floodplain meadows of the Deschampsion alliance. Vegetation of clusters 8 is characterized by species of the Phragmito-Magnocaricetea class and of the Deschampsion alliance, and occurs in wet nutrient-rich habitats. Vegetation of cluster 9, which usually develops from vegetation of cluster 8 due to decrease in the ground-water table, often contains species of dry grasslands and mesic meadows. Except for relevés of clusters 1 and 7, all others can be assigned to the Molinietum caeruleae Koch 1926 association. Cluster 1 corresponds to the Junco effusi-Molinietum caeruleae Tüxen 1954 association. Average Ellenberg indicator values for relevés, which were passively projected on the ordination biplot of detrended correspondence analysis, showed that the first ordination axis correlates with nutrients, soil base status and temperature, and second axis with moisture.  相似文献   

5.
Abstract

The Centaureo-Portenschlagiellion describes the cliff vegetation of the Southeastern Adriatic. This habitat type harbours many endemic taxa and has a high value for biodiversity conservation. Notwithstanding its importance, knowledge of the syntaxonomy of this alliance is still poor. This article aims at revising the synchorological, coenological and floristic relationships of the associations of the Centaureo-Portenschlagiellion. The revision is based on a data set of 103 relevés of Mediterranean xerothermic cliffs from Croatia, Bosnia i Herzegovina and Montenegro. The relevés were clustered by using the Flexible beta method. An indicator species analysis was used to identify the diagnostic taxa of the main clusters of relevés and non-metric multidimensional scaling ordination was undertaken to visualize the floristic relationships among them. Results revealed that only seven associations belong to the Centaureo-Portenschlagiellion, whereas the others already described in phytosociological literature were invalidly described or should be treated as syntaxonomic synonyms of the previous ones. Two associations (Inulo-Centaureetum cuspidatae and Portenschlagiello-Campanuletum portenschlagianae) were reduced to the rank of subassociations of the Moltkio-Inuletum verbascifoliae. Two other subassociations were described for the first time. Data provided with this revision may be considered as essential base-line information that should aid in evaluating the state of this vegetation type in the future.  相似文献   

6.
7.
The mapping and monitoring of Swiss mires has so far relied on a classification system based on expert judgement, which was not supported by a quantitative vegetation analysis and which did not include all wetland vegetation types described in the country. Based on a spatially representative sample of 17,608 relevés from 112 Swiss mires, we address the following questions: (1) How abundant are wetland vegetation types (phytosociological alliances) in Swiss mires? (2) How are they distributed across the country––is there a regional pattern? (3) How clearly are they separated from each other? (4) How clear and reliable is their ecological interpretation? Using published wetland vegetation relevés and lists of diagnostic species for phytosociological units (associations and alliances) established by experts, we developed a numerical method for assigning relevés to units through the calculation of similarity indices. We applied this method to our sample of 17,608 relevés and estimated the total area covered by each vegetation type in Switzerland. We found that vegetation types not included in previous mapping were either rare in Switzerland (partly due to mire drainage) or poorly distinguished from other vegetation units. In an ordination, the Swiss mire vegetation formed a triangular gradient system with the Sphagnion medii, the Caricion davallianae and the Phragmition australis as extreme types. Phytosociological alliances were clearly separated in a subset of 2,265 relevés, which had a strong similarity to one particular association, but poorly separated across all relevés, of which many could not be unequivocally assigned to one association. However, ecological gradients were reflected equally well by the vegetation types in either case. Overall, phytosociological alliances distinguished until now proved suitable schemes to describe and interpret vegetation gradients. Nevertheless, we see the urgent need to establish a data base of Swiss wetland relevés for a more reliable definition of some vegetation units.  相似文献   

8.
Hordeum geniculatum is considered as an obligate halophyte, but exact data about ecological requirements of the species are lacking. Therefore, species response curves of H. geniculatum were obtained for soil reaction and nutrients using Borhidi's indicator values and LOESS smoother response model in the programme CANOCO. Our data showed that H. geniculatum can be regarded as an obligate halophyte preferring slightly to moderately saline soils with relatively high content of nutrients. The Hordeetum hystricis association, indicating grazed vegetation on salt-rich soils, is a plant community that occurs only in central and southeastern Europe. Because this plant community has only been documented in a relatively small area, details about its vegetation ecology are inaccurate. Therefore, the ecology and species composition of this community were studied in three countries within the Pannonian Basin (Hungary, Serbia and Slovakia). A detrended correspondence analysis of 95 relevés from the Pannonian Basin confirmed that the community is characterised by the cover of H. geniculatum above 25%, which may even reach 75%. The association was species-rich; we sampled 91 taxa in 95 relevés. The widespread presence of many accessory species was dependent on environmental conditions, particularly the nutrient and salt content and animal disturbance.  相似文献   

9.
The marshland vegetation of the class Phragmito-Magnocaricetea in Croatia is presented in a single place for the first time. All the available relevés from the literature have been assembled and supplemented with the results of field research. Thirty-three communities have been established, shown in a synoptic table drawn up on the basis of 486 relevés. The communities are understood according to the traditional syntaxonomic system based on the dominant or diagnostic species. For the purposes of comparison, the marshland vegetation is classified using numerical methods as well. The results obtained show that most clusters correspond to specific associations, but do not confirm the division into vegetation alliances and orders. The marshland communities with the most relevés in the dataset, and that therefore can be considered the most widespread in Croatia, are: Phragmitetum australis, Caricetum gracilis, and Galio palustris-Caricetum ripariae. The marshland vegetation is also analysed from the standpoint of nature conservation. In the dataset studied, 59 taxa from the Red Book of Vascular Flora of Croatia are identified as threatened, the 15 most endangered marshland communities are separated, and 10 neophytes and one neophyte association are registered. The diversity of marshland vegetation, and of the associated plant species, is considerably higher in inland Croatia than along the Adriatic coast, which is probably a result of the geological bedrock, climate and, in some places, halophile conditions.  相似文献   

10.
Presented survey summarizes the results of the studies published predominantly after 2000, dealing with the plant communities around and above the timberline in (montane) subalpine to alpine (subnival) belt of the Western Carpathians. All of these communities underwent a critical syntaxonomical and nomenclatorical revision, hence the demonstrated overview of high-mountain vegetation of Western Carpathians (mostly from Slovakia, less from Poland border areas) represent the current state of knowledge. The high-altitude vegetation database, which is the part of Slovak National Vegetation Database, SNVD (), incorporated 8,160 published relevés on 15 May 2007 (of the total of 30,469 published relevés in the SNVD). Concerning the unpublished relevés, the individual authors have provided more than 18,400 of them to be stored in SNVD; 2,301 of all unpublished relevés could be assigned to high-altitude vegetation. Mountain and alpine vegetation is in SNVD presented by 15 classes; the most frequent class is Mulgedio-Aconitetea. With its quantity and also the quality of relevés, the high-altitude database, as well as the whole SNVD, represents the unique database within Slovakia, which provides information not only about the locality, floristic composition and variability of individual vegetation types, but also about several environmental variables such as inclination, aspect, geology or soil type, characteristic for individual relevés. Together with other Central European databases, SNVD takes up the leading position in Europe.  相似文献   

11.
Question: Is it possible to mathematically classify relevés into vegetation types on the basis of their average indicator values, including the uncertainty of the classification? Location: The Netherlands. Method: A large relevé database was used to develop a method for predicting vegetation types based on indicator values. First, each relevé was classified into a phytosociological association on the basis of its species composition. Additionally, mean indicator values for moisture, nutrients and acidity were computed for each relevé. Thus, the position of each classified relevé was obtained in a three‐dimensional space of indicator values. Fitting the data to so called Gaussian Mixture Models yielded densities of associations as a function of indicator values. Finally, these density functions were used to predict the Bayesian occurrence probabilities of associations for known indicator values. Validation of predictions was performed by using a randomly chosen half of the database for the calibration of densities and the other half for the validation of predicted associations. Results and Conclusions: With indicator values, most reléves were classified correctly into vegetation types at the association level. This was shown using confusion matrices that relate (1) the number of relevés classified into associations based on species composition to (2) those based on indicator values. Misclassified relevés belonged to ecologically similar associations. The method seems very suitable for predictive vegetation models.  相似文献   

12.
An overview of the coastal vegetation of Site of Community Importance “Zone Umide della Capitanata” (Puglia Region) is here presented. Original relevés were performed in different locations of the site. On the basis of the in-field observations (142 original relevés) and of literature data, 44 plant communities have been defined, belonging to the following classes: Lemnetea minoris, Ruppietea maritimae, Potametea pectinati, Phragmito-Magnocaricetea, Cakiletea maritimae, Ammophiletea, Helichryso-Crucianelletea maritimae, Juncetea maritimi, Sarcocornietea fruticosae, Saginetea maritimae, Thero-Suaedetea, Tuberarietea guattatae, Nerio-Tamaricetea. For each vegetation unit, the distribution area at local and regional level and the relation to habitat types of the 92/43 EEC Directive are provided.  相似文献   

13.
Abstract. The typology and distribution are discussed of hitherto poorly known Mediterranean-type maquis vegetation from the eastern stretch of the coastal fringe of the Cantabrian Mountains. 51 phytosociological relevés of maquis with Arbutus unedo (‘madroñales’) and Quercus coccifera (kermes oak shrubland or ‘coscojares’) were submitted to Correspondence Analysis and table rearrangement. The results are discussed and interpreted in the light of actual biogeographical and palaeohistorical knowledge. A sharp division between (uniform) acidophilous and (diversified) basophilous communities was revealed. On the basis of the phytosociological classification four new syntaxa are described: the associations Ulici gallii-Arbutetum unedonis, Phillyreo latifoliae-Arbutetum unedonis - with two subassociations: arbutetosum unedonis and viburnetosum tini - and the association Genisto occidentalis-Quercetum cocciferae.  相似文献   

14.
C. Blasi  G. Pelino 《Plant biosystems》2013,147(3):357-385
Abstract

The vegetation communities of the karst-tectonic basins of the Majella massif alpine belt were studied using the phytosociological methods, and analysed from coenological, synchorological and syntaxonomical viewpoints. During the field-work, 115 relevés were performed using the phytosociological approach of Braun-Blanquet, and these relevés were further subjected to multivariate analyses. Eight clusters of relevés resulted from the numerical classification. The plant communities identified in the study area were ascribed to the following five associations, two sub-associations and one community type: Leontopodio – Seslerietum juncifoliae (ass. nova); Helianthemo – Festucetum italicae (ass. nova); Gnaphalio – Plantaginetum atratae; Taraxaco – Trifolietum thalii gnaphalietosum magellensis (subass. nova); Luzulo italicae – Nardetum, Carici – Salicetum retusae; Saxifrago – Papaveretum julici, Saxifrago – Papaveretum androsacetosum (subass. nova), Plantago atrata and Leontodon montanus community. The distribution of these communities within the karst basins was found to be related to variations in topographic and geomorphological parameters, such as altitude, slope, soil availability and stoniness. All the new associations proposed in this paper belong to the suballiance Leontopodio – Elynenion and to the alliance Seslerion apenninae, both of which are endemic to the central Apennines. In order to compare the plant community types identified within the Majella massif to similar associations found in the rest of the Apennine chain, synoptic tables were constructed. Finally, a comparative phytogeographical analysis of the alpine belt vegetation of the Apennines, Dinarides, southern Balkans and eastern Alps is presented.  相似文献   

15.
ABSTRACT

Relationships between plant communities and the physical environment during primary succession on recently deglaciated glacier forelands were studied in 3 areas of the Italian Alps. The aim of the research was to relate traditional phytosociological data with environmental variables. Twenty-eight phytosociological relevés were performed, each associated with twenty-six environmental variables; quantitative parameters of richness and diversity were also calculated. Species/relevés, environmental variables/relevés and species/environmental variables matrices were analyzed by cluster analysis, PCA and Spearman correlation coefficient. Three main stages of succession were identified by floristic composition and confirmed by environmental parameter evaluation. A complex of environmental variables seems to be closely correlated with terrain age and richness/diversity parameters, even though diversity decreases in late successional stages. The phytosociological significance of species is in accordance with their position in the context of succession.  相似文献   

16.
Abstract. The first objective of this paper is to define a new measure of fidelity of a species to a vegetation unit, called u. The value of u is derived from the approximation of the binomial or the hypergeometric distribution by the normal distribution. It is shown that the properties of u meet the requirements for a fidelity measure in vegetation science, i.e. (1) to reflect differences of a species’relative frequency inside a certain vegetation unit and its relative frequency in the remainder of the data set; (2) to increase with increasing size of the data set. Additionally (3), u has the property to be dependent on the proportion of the vegetation unit's size to the size of the whole data set. The second objective is to present a method of how to use the value of u for finding species groups in large data bases and for defining vegetation units. A species group is defined by possession of species that show the highest value of u among all species in the data set with regard to the vegetation unit defined by this species group. The vegetation unit is defined as comprising all relevés that include a minimum number of the species in the species group. This minimum number is derived statistically in such a way that fewer relevés always belong to a species group than would be expected if the differential species were distributed randomly among the relevés. An iterative algorithm is described for detecting species groups in data bases. Starting with an initial species group, species composition of this group and the vegetation unit defined by this group are mutually optimized. With this algorithm species groups are formed in a data set independently of each other. Subsequently, these species groups can be combined in such a way that they are suited to define commonly known syntaxa a posteriori.  相似文献   

17.
The aim of this study was to estimate the influence of Ceratophyllum demersum L. and Stratiotes aloides L. on the species richness and phytocoenotic diversity of aquatic vegetation in lakes. The study was based on field investigations in the Łęczna-Włodawa Lake District located in mid-eastern Poland. The studied lakes (32) included both polymictic and dimictic reservoirs. Both in the polymictic and dimictic lakes, statistically significant correlation coefficients were obtained between the parameters that characterize Stratiotes aloides (the frequency in the phytosociological relevés, the percent share of Stratiotetum aloidis association in the phytolittoral) and those characteristic for species richness (the total number of hydromacrophytes, the number of charophytes, elodeids, nymphaeids and lemnids), phytocoenotic richness (the mean number of species in the phytosociological relevés) and phytocoenotic diversity (the Shannon–Wiener Index). The communities with a share of S. aloides are characterized by higher species richness. However, not a single case of statistically significant dependency was reported between the parameters that describe C. demersum (the frequency in the phytosociological relevés, the percent share Ceratophylletum demersi association in the phytolittoral) and the vegetation traits in both lake groups. Common occurrence of Stratiotes aloides might be considered to be evidence for good status of an aquatic ecosystem and a very good indicator of species richness and diversity of aquatic vegetation.  相似文献   

18.
Through tabular and average linkage cluster analyses, 872 phytosociological relevés, including 491 obtained from the literature and 381 of our own relevés obtained in the field, were ordered and classified. Based on these relevés, we then described and typified the associations, alliances, orders, subclasses, and classes defining the chionophilous communities of the boreal, temperate and Mediterranean climates of western North America. Diagnostic tables, ordination, clustering, and climatic, edaphic, and biogeographical data were used to establish floristic affinities among these syntaxa and interpret their distributions. Syntaxa were characterized by their floristic composition, physiognomy and biogeographical distribution, along with their position on the snow gradient. Finally, we ascribed the communities growing in temperate and Mediterranean climates to the new class Hieracio gracilis-Juncetea drummondii, including 3 subclasses, 6 orders, 12 alliances and 34 associations.  相似文献   

19.
The understanding of some plant communities can often be ambiguous if studies from multiple countries are considered, because goals and methods in each country may differ. The presented work is based on a detailed review of historic and recent literature about the association Heleochloëtum alopecuroidis in the Pannonian Basin and tangentially the adjacent regions within Central and SE Europe compared to authors’ field data. The named community was generally reported in moderately saline and marshy habitats in lowland areas, nevertheless it is not documented by phytosociological relevés to be part of the halophytic alliance of Cypero-Spergularion salinae. We performed a critical assessment of stands with the species Heleochloa alopecuroides in halophytic vegetation where we added our own data from field research between 2003 and 2013 (1044 phytosociological relevés) and 354 unpublished and published relevés taken from the three National Phytosociological Databases (Czech Republic, Hungary, Slovakia).We conclude that association Heleochloëtum alopecuroidis cannot be properly described as being part of the Pannonian halophytic vegetation group. It should be therefore deleted from the vegetation surveys.  相似文献   

20.
Abstract

This phytosociological study of the Carpathian species-rich mesophilous mountain hay meadows (Triseto flavescentis-Polygonion bistortae alliance, Molinio-Arrhenatheretea class) presents the first unified large-scale classification system in four countries: Slovakia, Poland, Romania and Ukraine. The starting dataset contained relevés of the Molinio-Arrhenatheretea, Mulgedio-Aconitetea and Nardetea strictae classes. Numerical classification and semi-supervised classification by K-means method were used for the analyses. An electronic expert system and diagnostic species for grassland vegetation served for identification of a priori groups in K-means method. The final dataset contained 612 relevés. Altitude, climatic data and Ellenberg indicator values were used for ecological differentiation of syntaxa. The main gradients in floristic composition were analysed by Detrended Correspondence Analysis. Finally, the eight well-differentiated associations and one newly described association were determined: Campanulo glomeratae-Geranietum sylvatici, Geranio sylvatici-Trisetetum flavescentis, Crepido mollis-Agrostietum capillaris, Geranio-Alchemilletum crinitae, Alchemillo-Deschampsietum caespitosae, Phyteumo (orbicularis)-Trifolietum pratensis, Astrantio-Trisetetum flavescentis, Trollio altissimi-Knautietum dipsacifoliae and Violo declinatae-Agrostietum capillaris ass. nova. The differences in vegetation diversity of mountain hay meadows between particular countries were confirmed: Alchemillo-Deschampsietum caespitosae occurs in all studied territories, Campanulo glomeratae-Geranietum sylvatici occurs predominantly in Slovakia and the newly described association Violo declinatae-Agrostietum capillaris ass. nova could be found only in Ukraine.  相似文献   

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