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1.
New syntaxa of different hierarchical levels are here described in order to update the “Syntaxonomic checklist of the Italian classes, orders and alliances (Vegetation Prodrome of Italy)”, promoted in 2012 by the “Ministry of Environment, Land and Sea Protection” in collaboration with the “Italian Society of Botany”. The new alliances, suballiances and associations belong to the Salici purpureae-Populetea nigrae and Querco roboris-Fagetea sylvaticae classes.  相似文献   

2.
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.
4.
Relationships between the spatial and temporal distribution of long-lasting snow-cover and the spatial distribution of plant communities above timberline were studied on Mount Prado (2054 m), a representative sample area of the summit vegetation of the Northern Apennines (Italy). The spatial analysis was carried out by creating a geographic information system. Vegetation map and two snow-cover maps were both georeferenced to a scale 1 : 2000. The vegetation map is formed by 28 plant communities (including 7 combinations of communities, or vegetation mosaics) distributed into 277 map polygons. The maps were compared by an overlay procedure. The results show that the six plant communities (including three mosaics) which have a June snow-cover higher than 60% are diversified by a snow-melting gradient from early June to mid-July. The slowest snow melt corresponds to a snow-bed community (Salicetum herbaceae) and to a mesophytic grassland (Trifolium thalii-Festuca puccinellii community, Luzula alpino-pilosa variant).  相似文献   

5.
This study presents the results of a floristic vegetational study on Robinia pseudoacacia neoformation forests in the peri-Adriatic sector of central Italy. This has allowed the characterization of these coenoses at the ecological, biogeographic, syntaxonomic and landscape levels. These currently represent the southernmost syntaxa of the Robinietea class described for the Italian peninsula, and the first syntaxonomic contribution of this class in Europe for the Mediterranean biogeographical region. We propose here the new alliance Lauro nobilis–Robinion pseudoacaciae of the order Chelidonio–Robinietalia pseudoacaciae and class Robinietea, with two new associations: Melisso altissimae–Robinietum pseudoacaciae and Rubio peregrinae–Robinietum pseudoacaciae. The new alliance Lauro nobilis–Robinion pseudoacaciae (typus: Melisso altissimae–Robinietum pseudoacaciae) brings together neoformation forests and pre-forest dominated by R. pseudoacacia in those territories with a Mediterranean macroclimate of the peri-Adriatic sector of central Italy. The optimum is found for the alluvial plain and low-slope morphologies, on soils that are moist and rich in organic matter and in areas with anthropic disturbance. On the basis of comparisons with the European context, the alliance Bryonio–Robinion described for the temperate territories of northern Italy is here validated.  相似文献   

6.
The importance of plant communities for conservation purposes is recognized in their inclusion in the “Habitat Directive” (92/43 EEC), that relates habitat types to plant community syntaxonomic units. However, habitat definitions in the Habitat Directive lead to several inaccuracies in local habitat characterization. Several wetland plant communities (and their corresponding habitats), rare in the Mediterranean basin, are not included in the Habitat Directive. This study proposes criteria for assessing the conservation importance of habitats. It deals with plant community types at the alliance level, as promising units for setting conservation priorities. The principle criteria considered as drivers for setting alliance conservation values are the distribution and abundance of plant species of conservation interest and their fidelity to a plant community. Multivariate methods were used, and a quantitative floristic index of alliance conservation priority was created. This procedure was applied to an important wetland in central Italy. Results emphasize: (i) high conservation values of some alliances not listed in the Habitat Directive, confirming various gaps in the current conservation law affecting Mediterranean wetlands; (ii) that habitats widely distributed in other biogeographical areas, may greatly underestimate their conservation importance in Mediterranean region; (iii) need to consider regional peculiarities when setting conservation priorities.  相似文献   

7.
Syntaxonomic diversity (SD) represents the number of plant communities (phytocoenoses) in certain area. Plant communities as organized systems of populations of various coexisting plant species inhabiting same or similar habitat in the function of time. SD is one of the best indicators of the state and potential carrying capacity of every ecosystem and an attribute of total ecological diversity. In general, level of syntaxonomic diversity indicates habitat heterogeneity and diversity. This could have significant importance in the categorization of habitat values in accordance with European Nature Information System (EUNIS) criteria. The results presented in this paper indicate without any doubt high natural values of mountain range Vranica in Bosnia and Herzegovina. One of the best proofs is an extremely high level of syntaxonomic diversity. In this area covering just 288 km2, vegetation is differentiated into 9 formations, 28 classes, 44 orders, 73 alliances and 165 associations. This represents 85% of all classes, 73% of all orders, 65% of all alliances, and 53% of all associations of vegetation in Bosnia and Herzegovina, or 35% of all classes in vegetation diversity in Europe. Going from the level of class to the level of order, the number of syntaxa increases for 61%, from order to alliance for 60%, and from alliance to association for 44.24% (average 55%). SD index is very high and it is 0.5729. This means that on each km2 contains 0.5729 syntaxa.  相似文献   

8.
Abstract

In Italy, Corynephorus communities are distributed along the medium course of the Ticino river and Sesia river and the internal sand dunes of Lomellina (through the Vercelli, Novara and Pavia provinces); these stations represent the southern limit of European distribution of this habitat. A phytosociological study was carried out to gain better knowledge of their composition; of their affinity or diversity against the central European communities; of their distribution and of the main threats to their conservation. Original and literature relevés (114) were elaborated producing a cluster analysis; correspondence analysis (CA), principal component analysis and Kruskal–Wallis test were carried on to characterize the clusters of relevés taking into consideration biological forms, chorological groups, Ellenberg indicator values and floristic groups. Italian Corynephorus communities can be attributed to the following syntaxa: Spergulo vernalis-Corynephoretum canescentis, Spergulo vernalis-Corynephoretum canescentis cladonietosum, Spergulo vernalis-Corynephoretum canescentis silenetosum nutantis and Spergulo vernalis-Corynephoretum canescentis artemisietosum campestris. Italian Corynephorus communities are included in the Habitat 2330 of the EU Habitat Directive. They are threatened by different factors (such as restricted areas of occurrence, alien plant invasion and natural dynamics) and they need to be managed if we want to conserve them.  相似文献   

9.
It is evident that some higher syntaxonomic unit above the classes is needed. The “circle of vegetation”, proposed byBraun-Blanquet is a geographical, not a synecological unit; the “formation”, recommended recently byPassarge, is based on physiognomy and therefore inconsistent with the principles of lower entities. The “division” proposed recently by Jakucs seems to be identical with the “type of vegetation”, published already 11 years ago by the present author.  相似文献   

10.
Summary The classical syntaxonomical treatment of the European Spartina communities as published in the series Prodrome of the the European plant communities, is compared with the results of a numerical treatment, based on largely the same set of relevés. 576 relevés, selected from the total salt marsh data set were subjected to agglomerative clustering with relocation with the similarity ratio as similarity measure. The resulting numerical system was compared with the syntaxonomical hierarchy. The correlation between both systems is close. The numerical units are slightly more heterogeneous because no purification occurred, which implies relevés to be left out of consideration. One new syntaxon, Spartinetum townsendii asteretosum tripolii, could be suggested from the results of the numerical treatment. Perspectives for the development of a numerical syntaxonomy are stressed.Communication number 40.  相似文献   

11.
In this paper the results of a study on the composition and the distribution of the plant communities in three coastal areas of southern Apulia are presented. A total of about 180 vegetation relevés were performed following the Braun-Blanquet phytosociological method. Vegetation data were analysed using both classification (UPGMA, similarity ratio) and ordination methods (including Non-metric Multidimensional Scaling (NMS) and Detrended Correspondence Analysis (DCA). The relevés are distributed in the following classes: Molinio-Arrhenateretea, Phragmito-Magnocaricetea, Juncetea maritimi, Sarcocornietea fruticosae, Saginetea maritimae, Thero-Salicornietea, Helianthemetea guttati. Detailed information about structure and zoning of the detected plant communities are here provided. Two new associations, belonging to the Alkanno-Maresion nanae alliance (microphytic ephemeral plant communities growing on sandy soils, Helianthemetea guttati class) have been described here, both in the “Torre Guaceto” site. The area of “Le Cesine” showed the highest total number of plant communities, while the “Saline di Punta della Contessa” site revealed the largest number of Sarcocornietea fruticosae plant communities.  相似文献   

12.
Abstract. Progress in the European Vegetation Survey is described. 25 countries are now represented in a network committed to common data standards in phytosociological survey, the development of compatible software for data analysis and mapping, the encouragement of national programmes and the development of an overview of European plant communities. Advances in each of these areas of activity is summarised and plans for the future are outlined, most notably the production of a book ‘The Vegetation of Europe’.  相似文献   

13.
In Italy, woods dominated by Quercus petraea are well documented within local and regional phytosociological studies but a critical revision of their principal ecological-floristic components based on a comprehensive Italian data set was missing. We gathered 209 published and unpublished Italian phytosociological relevés, where Q. petraea was dominant, that were investigated by means of multivariate analysis. The ecological requirements of the resulting groups were indirectly calculated by means of Ellenberg indicator value, and a chorological analysis was performed. The fidelity coefficient (phi) for the diagnostic species of each group was calculated. According to our analysis, five different types of Q. petraea woods were found to be present in Italy. Each group was characterized by means of its floristic, ecological and chorological components. These resulting five groups were further compared with similar Q. petraea-dominated woods recorded in other European locations, as to the floristic and chorological components. We collected 57 synoptic tables of Q. petraea communities coming from all over Europe. This data set, together with the Italian relevés, was submitted to exploratory multivariate analysis using also the chorological information. According to these analyses, the Italian woods dominated by Q. petraea can be subdivided in two main clusters: the communities belonging to It-1 group (Alps) fell within the central European communities, distinguished by the predominance of large distribution and European chorotypes. All the other Italian groups of relevés resulted to be positioned in the cluster which includes central southern, central eastern and eastern European Q. petraea communities. From the syntaxonomical point of view, the results of this analysis allow to attribute the Italian Q. petraea woods to seven alliances of three different orders. The ecological similarities between Erythronio-Quercion petraeae and Erythronio-Carpinion betuli are highlighted and the distribution of Erythronio-Quercion petraeae is limited to northern Apennines, in particular, to slopes facing the Po Valley.  相似文献   

14.
Rice blast disease, caused by the fungus Pyricularia grisea (Cooke) Sacc., is responsible for considerable damages in rice crops in Italy and in other parts of the world. This study was conducted in order to investigate the genetic structure of a P. grisea population in the Po area, the largest rice area in Italy. Rice leaves showing blast symptoms were collected in three successive years (1998–2000) and 43 P. grisea monoconidial culture samples were isolated from infected rice leaves. Fungal DNAs were obtained from mycelia. Moreover, six additional P. grisea DNA samples representative for the five characterized European lineages were also investigated. All 49 DNAs were fingerprinted using the Pot2‐based repetitive polymerase chain reaction specific for the blast pathogen. Unweighted pair‐group method with arithmetic averages cluster analysis shows the presence of three main Italian lineages. Within lineages, similarity was higher than 80%. Samples representative of the three of five known European lineages grouped within these three Italian lineages confirming the presence of three European lineages in Italy. Furthermore, cluster analysis shows the presence of two new haplotypes never found before in the Italian lineage.  相似文献   

15.
We investigated spontaneous vegetation succession and the relationship between time and vegetation patterns in several abandoned quarries of the Botticino extraction basin (Lombardy, Italy) and then assigned plant assemblages to a predetermined theoretical successional phase using an original procedure. To recognise and validate the gradient due to time, an ordination approach of vegetation plots linked to constant variables and time since last mining Canonical Correspondence Analysis was conducted first. Then, to determine the durations of the vegetation succession phases and trends between the colonisers and late successional species, we used an original six-step procedure based primarily on the regression curve of the percent relative abundance of life forms (RALFs) over time. The results demonstrated that time is the primary factor that significantly affects life form turnover during succession. Vegetation establishment and development in the “pioneer phase” (0–6 years) were affected by abiotic filters, which determined the dominance of a few ruderal and annual/alien species, mostly therophytes. The successive phases were characterised by an increasing presence of perennial species (mostly phanerophytes) with a consequent influence of biotic filters. The RALF procedure may be applied to other environments to investigate the time trends of plant communities during successions.  相似文献   

16.
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   

17.
Abstract. Plant communities of trampled soil dominated by plants characterized by the C4-assimilation syndrome were investigated in Europe. These species, belonging to genera such as Chamaesyce, Amaranthus, Eleusine, Eragrostis and Setaria, are thermophilous, late-germinating, prostrate herbs or grasses. The centre of their distribution is in the (Sub)Tropics. A syntaxonomic revision of the phytosociological material from Europe (incl. the Macaronesian Archipelago) revealed three alliances: the Euphorbion prostratae from Spain, the Polycarpo-Eleusinion indicae from Italy, and Slovenian and Croatian Istria, and the Eragrostio-Polygonion arenastri from temperate regions of Europe. The latter two syntaxa are described as new. All three alliances belong to the order Eragrostietalia (class Stellarietea mediae). Vicarious (ecologically analogous) communities occur also in southern Africa, eastern Asia and North America. The communities studied in the present paper are considered to be an impoverished form of highly diversified trampled plant communities typical of (sub)tropical areas.  相似文献   

18.
Summary

Introduction to the Study of Plant Cover of Anthropic Stations in Italy.

The present work is introductory to a series of special papers dealing with Italian farm-land weeds and ruderal plants.

The Author attempts to lay down the general criteria for the study, of the antropic communities of the earth's vegetation. He points out the great ecological and phytogeographical interest of those plant communities which are directly conditioned by man, seen as a widespread experiment in soil occupation by plants and in the “settling-down” process of mature vegetal cover, in such peculiar stations as the anthropic ones. This natural experiment is going on all the time and has in itself the possibility of leading towards characteristic oecological settlements of plants, biological competition, and — possibly · specific mutations.  相似文献   

19.
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   

20.
Italy is the largest rice‐producing country in the European Union. In Italy, only japonica cultivars are listed in the Italian National Register. Almost all of the rice production is concentrated in the Po Valley, where the rice water weevil Lissorhoptrus oryzophilus Kuschel was first detected and settled. This study investigated the performance of this pest in terms of feeding, reproduction and plant injury on 10 rice cultivars chosen among the most widely grown in Italy. No‐choice experiments were conducted to evaluate the plant susceptibility to larval attack and to find out how cultivars can influence the adult leaf area consumption. The results gave evidence of different types of attack depending on the density of the insect (0.6 adults/plant vs. 0.9 adults/plant), the cultivar type and climatic conditions. Different cultivars with the same level of infestation gave different results in terms of productivity. Production was significantly affected by the larval presence in 4 of the 10 cultivars tested. A different population structure reflected a different damage severity. Statistically different values for total adult leaf area consumption were found according to adult female age and to the cultivar.  相似文献   

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