scholarly journals Dry Grasslands in the Slovenský Kras MTS (Slovakia) and the Aggteleki-karszt MTS (Hungary) — A Comparison of Two Classification Approaches

Hacquetia ◽  
2008 ◽  
Vol 7 (2) ◽  
pp. 123-140 ◽  
Author(s):  
Daniela Dübravková-Michálková ◽  
Monika JanišOvá ◽  
Jiří Kolbek ◽  
Róbert Šuvada ◽  
Viktor Virók ◽  
...  
Keyword(s):  
Expert System ◽  
Central Europe ◽  
Numerical Classification ◽  
Grassland Vegetation ◽  
Dry Grassland ◽  
Dry Grasslands ◽  
Unsupervised Method ◽  
Formal Definitions ◽  
Phytosociological Relevés

Dry Grasslands in the Slovenský Kras MTS (Slovakia) and the Aggteleki-karszt MTS (Hungary) — A Comparison of Two Classification ApproachesThe paper brings numerical classification of 48 new phytosociological relevés of dry grassland vegetation from the Slovenský kras Mts and the Aggteleki-karszt Mts located on the border between Slovakia and Hungary (Central Europe). We performed a comparison of two classification approaches (an unsupervised method - modified TWINSPAN, and a supervised approach - electronic expert system based on formal definitions of associations), which were applied on the same dataset. Four associations were distinguished:Campanulo divergentiformis-Festucetum pallentisZólyomi (1936) 1966,Poo badensis-Caricetum humilis(Dostál 1933) Soó ex Michálková in Janišová et al. 2007,Alysso heterophylli-Festucetum valesiacae(Dostál 1933) Kliment in Kliment et al. 2000 andFestuco rupicolae-Caricetum humilisKlika 1939. A newly recorded stand of the rareStipetum tirsaeMeusel 1938 association is characterised. What is more, we established a neotype of theAlysso heterophylli-Festucetum valesiacaeassociation.

Numerical classification of French vegetation of Carici caryophylleae – Genistetea lobelii J.-C. Klein 1972

2021 ◽  
Vol 42 ◽  
pp. e68062
Author(s):  
Pauline Delbosc ◽  
Mathieu Le Dez ◽  
Jean-Bernard Bouzillé ◽  
Kevin Cianfaglione ◽  
Frédéric Bioret
Keyword(s):  
Expert System ◽  
Dominant Species ◽  
Numerical Classification ◽  
Distribution Map ◽  
Diagnostic Species ◽  
Plant Associations ◽  
Formal Definitions ◽  
Twinspan Classification ◽  
New Association

Carici-Genistetea lobelii Klein 1972 corresponds to cyrno-sardinian oromediterranean cushion scrub and related grasslands. In France, this class is only present in Corsica and the syntaxonomic scheme is debated among phytosociologists. The aim of this paper is to highlight the main plant associations of Carici-Genistetea lobelii Klein 1972 and to define the diagnostic species for each phytosociological unit. We compiled 519 vegetation plots and we applied EuropeanVegetationChecklist expert system for the classes of European vegetation to retain only vegetation plots belonging to Carici-Genistetea lobelii. We obtained a dataset with 189 vegetation plots and we classified them with Modified TWINSPAN classification. Our analyses recognized 6 plant associations and 3 sub-associations already described in the literature; and to describe a new alliance corresponding to the supra-mediterranean vegetations (Genistion salzmannii), a new association (Brimeuro fastigiatae-Juniperetum nanae) and its sub-association (alnetosum suaveolentis). For each of them, we identified diagnostic, constant and dominant species and produced their distribution map. Formal definitions were then written for each phytosociological unit (from subassociation to class) and grouped in an expert system to automatically classify the vegetations of Carici-Genistetea lobelii.

scholarly journals Dry Grassland Vegetation in the Transition Zone Between two Biogeographic Regions

Hacquetia ◽  
2014 ◽  
Vol 13 (1) ◽  
pp. 79-120 ◽  
Author(s):  
Desislava Sopotlieva ◽  
Iva Apostolova
Keyword(s):  
Soil Moisture ◽  
Soil Depth ◽  
Humus Content ◽  
Life Forms ◽  
Grassland Vegetation ◽  
Data Set ◽  
Total N ◽  
Dry Grassland ◽  
Dry Grasslands ◽  
Biogeographic Regions

Abstract The geographic position of Bulgaria results in a variety of climatic and biogeographic influences on the country’s vegetation. We aim to describe the plant diversity of dry grasslands distributed in the transitional belt between the south-eastern European and Mediterranean biogeographic regions in SE Bulgaria, and to reveal if there are any obvious differences in soil properties, presence of life forms and chorotypes between syntaxa. The data set consists of 349 releves of vascular plants and bryophytes sampled in different semi-natural herbaceous vegetation types. By applying TWINSPAN, we classified 176 releves of dry grasslands to eight associations and one unranked community. One association and two subassociations are described here for the first time. Data on soil depth, soil moisture, soil pH, humus and total N content, numbers of different life forms and chorotypes were analysed statistically. The dry grasslands in SE Bulgaria were classified into different vegetation classes sharing the same territory: their communities present similarities in species composition and they have similar ratios of hemicryptophytes/therophytes and Euro-Asiatic/Mediterranean species. Dry grassland vegetation occupies mostly shallow and dry soils that vary slightly in pH, humus content and soil moisture between associations.

Classification of dry grassland vegetation in Denmark

2000 ◽  
Vol 11 (4) ◽  
pp. 585-596 ◽  
Author(s):  
Hans Henrik Bruun ◽  
Rasmus Ejrnaes
Keyword(s):  
Grassland Vegetation ◽  
Dry Grassland

scholarly journals Formalized Hierarchically Nested Expert System for Classification of Mesic and Wet Grasslands in Poland

2021 ◽  
Vol 89 (4) ◽  
Author(s):  
Zygmunt Kącki ◽  
Grzegorz Swacha ◽  
Attila Lengyel ◽  
Joanna Korzeniak
Keyword(s):  
Expert System ◽  
Classification System ◽  
Hierarchical Level ◽  
Formal Definitions ◽  
Wet Grasslands ◽  
Species Groups ◽  
Definition Of ◽  
The Given ◽  
Vegetation Patches

The goal of this study was to propose a hierarchically nested classification system comprising four principal levels of the Braun-Blanquet system for Polish grasslands of the class <em>Molinio-Arrhenatheretea</em>. Using the Cocktail method, we defined consistent criteria for delimitation of the class, three orders, nine alliances, and 45 associations. Formal definitions were prepared using the summed cover and presence/absence information of species groups and individual dominant species. We created an expert system with a set of assignment rules that unambiguously classify relevés to a single unit at the given abstraction level of the Braun-Blanquet system in such a way that a relevé matched by the definition of a focal vegetation unit must be matched by definitions of all superior units. Of 11,535 relevés classified to <em>Molinio-Arrhenatheretea</em>, 36% were recognized at the association level, and 57% and 85% at the alliance and order level, respectively. All relevés were assigned unambiguously, meaning that a single relevé could not be assigned to more than one unit within the same hierarchical level (no overlap between vegetation units). This study is the first proposal of a hierarchically nested classification system that classifies grassland vegetation at different syntaxonomical levels unequivocally. It is important to create definitions for different syntaxonomical levels because the majority of vegetation patches do not fit to the associations, but can only be assigned to high-rank units such as alliance, order, or class.

scholarly journals Zbiorowiska namułkowe z klasy Isoëto-Nanojuncetea Br.-Bl. et Tx. 1943 w Polsce [Occurrence of the Isoëto-Nanojuncetea-class communities in Poland]

2014 ◽  
Vol 80 ◽  
pp. 1-59 ◽  
Author(s):  
Agnieszka Popiela
Keyword(s):  
Western Europe ◽  
Group Method ◽  
Numerical Classification ◽  
Character Species ◽  
Pair Group ◽  
Open Questions ◽  
Phytosociological Relevés ◽  
Complete Catalogue ◽  
Made In

The <em>Isoëto-Nanojuncetea</em>-class includes short-lived and ephemerical communities occurring on temporarily flooded places in Western, Southern and Central Europe and Northern Africa. Results of the numerical classification of 739 phytosociological releves of the communities occurring in Poland are presented and discussed. Ali the releves were made in accordance with the principles of the BRAUN-BLANQUET school of syntaxonomy. The calculations were performed using NCLAS program of the SYN-TAX IV package. The JACCARD formuła and the unweighted pair-group method, using arithmetic averages (UPGMA) were applied. There is a strong habitat and floristic differentation of the communities of the <em>Isoëto-Nanojuncetea</em>-class occurring in Poland. The results of the numerical classification indicate that, the distuinguished communities belong to two alliances: the <em>Radiolion linoidis</em> (Rivas Goday 1961) Pietsch 1965 (for associations occurring on synanthropic localities like stubble fields) and the <em>Elatini-Eleocharition ovatae</em> Pietsch 1965 (for communities growing on bottoms of dried ponds and exposed river or lakę banks). The distinguished communities arę phytosociologically characterized on basis of 223 selected releves. These arę: <em>Spergulario-Illecebretum verticillati, Ranunculo-Myosuretum minimi, Centaurium pulchellum-Pottia truncata-commumiy, Heleocharetum ovatae, Cyperetum flavescentis</em> and <em>Cyperus fuscus-Limosella aquatica</em>-commumiy. The study focused on: (1) attempting to solve the problem of phytosociological classification for the communities occurring in Poland, (2) preparing a complete catalogue of them and (3) giving the full list of character species (also among bryophytes) of distinguished syntaxa. It has led to finding out the relation between the communities occurring in Poland and the associations of Western Europe. The problem of the naturality of certain distinguished associations was discussed. The paper gives also some open questions demanding further studies and some suggestions of methods to be applied.

scholarly journals Legacies of past land use challenge grassland recovery – An example from dry grasslands on ancient burial mounds

2020 ◽  
Vol 39 ◽  
pp. 113-132
Author(s):  
Balázs Deák ◽  
Orsolya Valkó ◽  
Csaba Albert Tóth ◽  
Ágnes Botos ◽  
Tibor József Novák
Keyword(s):  
Land Use ◽  
Large Scale ◽  
Forest Steppe ◽  
Residual Soil ◽  
Grassland Vegetation ◽  
Dry Grassland ◽  
Dry Grasslands ◽  
Arable Farming ◽  
Habitat Islands ◽  
Burial Mounds

Due to large-scale agricultural intensification, grasslands are often restricted to habitat islands in human-transformed landscapes. There are approximately half a million ancient burial mounds built by nomadic steppic tribes in the Eurasian steppe and forest steppe zones, which act as habitat islands for dry grassland vegetation. Land use intensification, such as arable farming and afforestation by non-native woody species are amongst the major threats for Eurasian dry grasslands, including grasslands on mounds. After the launch of the Good Agricultural and Environmental Condition framework of the European Union, in Hungary there is a tendency for ceasing crop production and cutting non-native woody plantations, in order to conserve these unique landmarks and restore the historical grassland vegetation on the mounds. In this study, restoration prospects of dry grassland habitats were studied on kurgans formerly covered by croplands and Robinia pseudoacacia plantations. Soil and vegetation characteristics were studied in thespontaneously recovering grasslands. The following questions were addressed: 1; How does site history affect the spontaneous grassland recovery? 2; Do residual soil nutrients play a role in grassland recovery? In former croplands, excess phosphorus, while in former Robinia plantations, excess nitrogen was present in the soil even four years after the land use change and grassland vegetation was in an early or mid-successional stage both on the mounds. The results showed that, without proper management measures, recovery of grassland vegetation is slow on mounds formerly used as cropland or black locust plantation. However, restoration efforts, focused on the restoration of mounds formerly covered by croplands, can be more effective compared to the restoration of mounds formerly covered by forest plantations.

scholarly journals Ecological Evaluation of Grassland Vegetation in Hodrušská Hornatina Highland

2020 ◽  
Vol 39 (3) ◽  
pp. 236-249
Author(s):  
Alexandra Klimantová
Keyword(s):  
Species Composition ◽  
Environmental Variables ◽  
Environmental Gradient ◽  
Detrended Correspondence Analysis ◽  
Grassland Vegetation ◽  
Ecological Evaluation ◽  
Factors Affecting ◽  
Phytosociological Relevés ◽  
Grassland Communities

AbstractIn the submitted paper, we have analysed the results of a systematic survey of grassland communities, performed in Hodrušská hornatina highland, in Štiavnické vrchy mountains. The main aims of the research were: i) syntaxonomical classification of grassland vegetation; ii) analysis of the main ecological gradients in species composition; iii) evaluation of the influence of environmental factors on species composition of grasslands. The dataset included 153 phytosociological relevés recorded on grasslands. Grassland communities were classified within five associations: Holcetum lanati, Pastinaco sativae-Arrhenatheretum elatioris, Alchemillo-Arrhenatheretum elatioris, Anthoxantho odorati-Agrostietum tenuis, Onobrychido viciifoliae-Brometum erecti; and the successional and transitional stages belonging to alliances Arrhenatherion elatioris and Bromion erecti. The results of the Detrended Correspondence Analysis support our assumption that the main environmental gradient in species composition on grassland is related to moisture. The results of the Redundancy Analysis show that all used environmental variables explained 3.4% of the variability of the species data. The most important factors affecting the species composition were altitude, slope, distance from settlements, and management.

scholarly journals Local ranges of phytosociological associations: are they reflected in numerical classification?

Biologia ◽  
2006 ◽  
Vol 61 (1) ◽  
Author(s):  
Ilona Knollová ◽  
Milan Chytrý ◽  
Lubomír Tichý ◽  
Ondřej Hájek
Keyword(s):  
Czech Republic ◽  
Species Composition ◽  
Large Scale ◽  
Vegetation Classification ◽  
Numerical Classification ◽  
The Czech Republic ◽  
Small Areas ◽  
Phytosociological Relevés ◽  
Total Species

AbstractIn the tradition of European phytosociology, delimitations of vegetation units such as associations are mostly based on data from small areas where more detailed vegetation sampling has been carried out. Such locally delimited vegetation units are often accepted in large-scale synthetic classifications, e.g. national vegetation monographs, and tentatively assigned to a small geographical range, forming groups of similar (vicarious) vegetation units in different small areas. These vicarious units, however, often overlap in species composition and are difficult to recognize from each other. We demonstrate this issue using an example of the classification of dry grasslands (Festuco-Brometea) in the Czech Republic. The standard vegetation classification of the Czech Republic supposes that the majority of accepted associations (66 out of 68) have a restricted distribution in one of the two major regions, Bohemia or Moravia. We compared the classification into traditional associations with the numerical classification of 1440 phytosociological relevés from the Czech Republic, in order to test whether the traditionally recognized associations with small geographical ranges are reflected in numerical classification. In various comparisons, the groups of relevés identified by numerical analysis occupied larger areas than the traditional associations. This suggests that with consistent use of total species composition as the vegetation classification criterion, the resulting classification will usually include more vegetation units with larger geographical ranges, while many of the traditional local associations will disappear.

Sign in / Sign up

Export Citation Format

Share Document