Questions
What vegetation types can be distinguished on the basis of plant functional traits using numerical classification? How do they match syntaxonomical units?
Location
Poland.
Methods
Six ...thousand nine hundred and eighty‐five vegetation plots representing mesic and wet grasslands (Molinio‐Arrhenatheretea, Polygono‐Poetea) were retrieved from the Polish Vegetation Database. Plant functional trait data were assembled from the LEDA and Clo‐Pla databases for most species occurring in the data set. Community‐weighted mean for five traits were calculated for each plot: specific leaf area, canopy height, seed mass, bud bank index and clonality index. Plots were classified using Ward's method and iterative relocation based on silhouette widths. The clusters were interpreted and characterized on the basis of species and trait composition, functional diversity, functional redundancy, Ellenberg indicator values, and geographical distribution. The similarity between the trait‐based classification and the syntaxonomical assignment of plots is evaluated both statistically and by expert knowledge.
Results
Twelve clusters were distinguished. The classification mirrored the main gradients structuring grasslands in Poland, although, some vegetation types with the strong dominance of functionally unique species appeared more distinct than they are treated in syntaxonomy. Clusters did not differ significantly in functional diversity and redundancy. The differences of clusters in species and trait composition and environmental background are discussed.
Conclusion
The application of trait data and numerical methods is a promising approach for obtaining vegetation classifications. Such classifications can be in closer relationship with the most important ecosystem processes than floristic classifications because communities comprising different species but similar functional trait distribution are not separated. Trait‐based classifications match phytosociological units to a variable degree. Functional uniqueness and variation of abundance determines how individual species influence the delimitation of vegetation types using our approach.
We prepared the numerical classification of mesic and wet grasslands of Poland on the basis of community‐weighted mean plant traits of phytosociological relevés. The trait‐based classification matched floristically defined units to a variable degree. Functional uniqueness and variation of abundance determined how individual species influence the delimitation of vegetation types using our approach.
This paper presents a phytosociological study of dry and mesophilous meadows and pastures in the Locarnese region (Insubria - Southern Switzerland). Seventy-one vegetation relevés were analysed ...using both hierarchical classification and nonmetric multidimensional scaling (NMDS) ordination. Seven main clusters were identified and described as follows: (i) xerophytic grasslands on sandy soil dominated by
Koeleria macrantha
; (ii) mesophilous meadows with
Arrhenatherum elatius
and
Centaurea transalpina
; (iii) semi-dry meadows with
Chrysopogon gryllus
; (iv) semi-dry grasslands with
Carex fritschii
and
Thalictrum minus
; (v) nutrient-poor
Phyteuma betonicifolium-Festuca nigrescens
montane zone grasslands;
Nardus stricta
grasslands dominated by (vi)
Festuca paniculata
or (vii)
Carex pilulifera
. From a phytosociological point of view, a new association named
Phyteumo betonicifolii-Festucetum nigrescentis
, classified into the
Nardo strictae-Agrostion tenuis
alliance was proposed. In addition, we confirmed the presence of the
Holco-Chrysopogonetum grylli
association, within the
Bromion erecti
, which up to now was provisional only.
Se describe una nueva asociación vegetal, Erico terminalis-Schoenetum nigricantis (All. Molinio-Holoschoenion vulgaris), dominada por Schoenus nigricans, Erica terminalis y E. erigena, que resulta ...endémica de las áreas termomediterráneas de las sierras de elevación media o baja del sur de la provincia de Valencia. Es un juncal negro de alta densidad, pero florísticamente muy pobre, que crece en la base de balmas y roquedos calizos rezumantes, donde se acumulan tobas calcáreas y depósitos te¬rrosos, que permanecen húmedos buena parte del año gracias a surgencias temporales de agua. Se apor¬tan asimismo datos sobre la composición florística, comportamiento ecológico, distribución y relaciones de esta comunidad con otras de similar fisonomía. Paralelamente, se realiza la corrección nomenclatural del matorral setabense Thymo piperellae-Helianthemetum rotundifolii Rivas Goday 1958 corr. Solanas & M.B. Crespo hoc. loc. Thymo piperellae-Helianthemetum mollis Rivas Goday 1958, nom. incorr., dado que el taxon que da nombre a la asociación es realmente Helianthemun rotundifolium y no H. molle o H. marifolium, como se ha indicado en ocasiones. A new endemic plant association, Erico terminalis-Schoenetum nigricantis (All. Molinio-Holoschoenion vulgaris), is described from the thermomediterra¬nean areas of the low- or medium-elevation mountains of the southern parts of Valencia province, which is dominated by Schoenus nigricans, Erica terminalis and E. erigena. This is a dense but poorly charac¬terised black-sedge community, occurring at the base of “balmas” and dripping limestone cliffs, where deposits of tufa or clay are formed which remain sodden during part of the year due to water emergence. Data on the floristic composition, ecology, distribution and sintaxonomic relationships of this habitat are also reported with regard to other similar communities. Furthermore, the nomenclatural correction Thymo piperellae-Helianthemetum rotundifolii Rivas Goday 1958 corr. Solanas & M.B. Crespo hoc. loc. Thymo piperellae-Helianthemetum mollis Rivas Goday 1958, nom. incorr. is stated, since the taxon used to name that Saetabensian scrub is indeed Helianthemun rotundifolium, neither H. molle nor H. marifolium as sometimes it was suggested.
Agro-pastoral decline in European mountain areas has recently caused changes to traditional landscapes with negative consequences on semi-natural grassland conservation and the associated ...biodiversity and ecosystem services. In the Italian Alps, grassland patches enclosed in a forest matrix are progressively disappearing. Two alpine valleys (Pesio and Pejo), having similar land-use history, were chosen as representative of management conditions of western and eastern Italian Alps, respectively. This study aims at interpreting the effect of abandonment on grassland patch plant diversity, considering land cover changes of the last 60 years, and assessing the role of ecological, topographic, management and landscape configuration on current grassland species richness. The total area of grassland patches has declined by 54 and 91 % at Pesio and at Pejo, respectively. Actual grassland patch species richness was mostly influenced by ecological factors, such as quantity of light, soil moisture and reaction, then by topographic features, especially slope, and finally by management intensity. Landscape factors exerted a slightly significant effect on plant diversity. In the two valleys, differences on management practices were detected. Even though in the western valley the conservation of several grazing activities contributed to slow down the process of patch reduction, many species-rich grasslands were generally under-grazed. Conversely, in the eastern valley, despite a denser road network, the stronger decline of grassland patch extension was linked to the hay making decline. At the same time, overuse of grassland patches near farms reduced plant species richness. As a conclusion, plant species richness was weakly related to the area of grassland patches and current and historical landscape configuration were of relatively lower importance than ecological, topographic and management factors, when evaluated at patch-level.
The diversity of mesic and wet grasslands for the north part of the steppe zone in the Southern Bug River basin is characterized by the example of Buzkyi Gard National Nature Park and adjacent ...territories. I classified 39 vegetation relevés with quantitative classification methods (JUICE, TWINSPAN modified algorithm) and obtained seven clusters, which represent three associations, three communities and one derivate community within six alliances (Agrostion vinealis, Althaeion officinalis, Arrhenatherion elatioris, Convolvulo arvensis-Agropyrion repentis, Potentillion anserinae, Veronico longifoliae-Lysimachion vulgaris). Using Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA) and Didukh’s ecological scales, I determined the main environmental factors, which explain differentiation of the resulted vegetation units: variability of damping, salt regime of a soil, soil moisture, soil aeration, carbonate content in a soil, light. Characterized vegetation corresponds to six habitat types of the EUNIS classification (R21, R22, R35, R36, R55, V38). I also reviewed the major factors of negative impact on the meadow vegetation of the territory, in particular the changes of traditional land use in the last decades and their consequences. The main measures of management for studied communities should be mowing, moderate grazing, and removal of tree and shrub species if necessary.
We characterize geobotanically the mesohygrophilous grasslands dominated by Carex otrubae or Cyperus longus of the Iberian Peninsula and, to a lesser extent, of the rest of Western Europe. We ...compared 26 own relevés, carried out in Catalonia (NE Iberian Peninsula) according to the Braun-Blanquet phytosociological methodology, with 239 bibliographic relevés from Western Europe (56 from the Iberian Peninsula and Balearic Islands) using the K-means clustering and the comparison of synoptic relevés. The results show the clear separation of 11 different associations, including three new ones, ascribable to two different phytosociological classes: Molinio-Arrhenatheretea (Mentho-Cyperetum longi ass. nov., Ranunculo-Cyperetum longi ass. nov., Lythro-Caricetum otrubae ass. nov., community of Cyperus longus with Mentha pulegium, Cypero-Caricetum otrubae, Holco-Cyperetum longi stat. nov., community of Carex otrubae with Atriplex prostrata, and Caricetum otrubae-camposii) and Phragmito-Magnocaricetea (Cyperetum longi, community of Carex otrubae with Juncus effusus, and Sparganio-Cyperetum longi).
Caracterizamos geobotánicamente los herbazales mesohigrófilos dominados por Carex otrubae o Cyperus longus de la península ibérica y, en menor medida, del resto de Europa occidental. Hemos comparado 26 inventarios propios, levantados en Cataluña (NE de la península ibérica) según la metodología fitosociológica de Braun-Blanquet, con 239 inventarios bibliográficos de Europa occidental (56 de la península ibérica e islas baleares) mediante el algoritmo K-means y la comparación de inventarios sintéticos. Los resultados muestran la separación clara de 11 asociaciones distintas, entre ellas tres de nuevas, adscribibles en dos clases fitosociológicas diferentes: Molinio-Arrhenatheretea (Mentho-Cyperetum longi ass. nov., Ranunculo-Cyperetum longi ass. nov., Lythro-Caricetum otrubae ass. nov., comunidad de Cyperus longus con Mentha pulegium, Cypero-Caricetum otrubae, Holco-Cyperetum longi stat. nov., comunidad de Carex otrubae con Atriplex prostrata, y Caricetum otrubae-camposii), y Phragmito-Magnocaricetea (Cyperetum longi, comunidad de Carex otrubae con Juncus effusus, y Sparganio-Cyperetum longi).
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 ...Molinio-Arrhenatheretea. 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 releves to a single unit at the given abstraction level of the Braun-Blanquet system in such a way that a releve matched by the definition of a focal vegetation unit must be matched by definitions of all superior units. Of 11,535 releves classified to Molinio-Arrhenatheretea, 36% were recognized at the association level, and 57% and 85% at the alliance and order level, respectively. All releves were assigned unambiguously, meaning that a single releve 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. Keywords Cocktail method; vegetation classification; Molinio-Arrhenatheretea; syntaxonomy; diversity; Braun-Blanquet approach
Question: What are the community types, underlying gradients and phytogeographical affinities of montane meadows in the western Tien Shan? Location: Aksu-Jabagly Nature Reserve, South Kazakhstan, ...Middle Asia. Methods: Species composition, structural and environmental variables were studied in 98 plots. Species composition was classified by cluster analysis and gradients explored using NMDS. Relationships between species richness, environmental and structural variables were investigated with regression analysis. Phytogeographic patterns were assessed by examining species distribution types. Results: Seven community types were distinguished by cluster analysis. Three axes of the NMDS explained 77% of the variation, showing different overlap of communities with environmental and structural properties. Species richness showed linear relationships with pH, altitude, heat load, soil skeletal content and structural variables. Middle Asian and Eurosiberian species constituted the majority of the species pool and cover. Conclusion: The studied communities represent a unique mixture of Middle Asian and Eurosiberian species that exhibit structural and environmental similarities to Eurosiberian meadows. The Tien Shan mountain meadows can thus be considered an endemic-rich southern outlier of the broader Eurosiberian meadow formation. Shifts in land-use patterns pose a potential threat that deserves more attention from conservationists.
Aims
: To clarify the syntaxonomic position of the grasslands in Navarre, with special focus on the dry grasslands, and to characterise the resulting syntaxonomic units in terms of diagnostic species ...and ecological conditions.
Study area
: Navarre (northern Spain).
Methods
: We sampled 119 plots of 10 m
2
following the standardised EDGG methodology and analysed them together with 839 plots of similar size recorded in the 1990. For the classification, we used the modified TWINSPAN algorithm, complemented by the determination of diagnostic species with phi coefficients of association, which led to the creation of an expert system. We conducted these steps in a hierarchical manner for each syntaxonomic rank. We visualised the position of the syntaxa along environmental gradients by means of NMDS. Species richness, and structural and ecological characteristics of the syntaxa were compared by ANOVAs.
Results
: We could clearly identify five phytosociological classes:
Lygeo-Stipetea, Festuco-Brometea, Molinio-Arrhenatheretea, Nardetea strictae
, and
Elyno-Seslerietea
. Within the
Festuco-Brometea
a xeric and a meso-xeric order could be distinguished, with two alliances each, and eight associations in total:
Thymelaeo-Aphyllanthetum, Jurineo-Festucetum, Helianthemo-Koelerietum, Prunello-Plantaginetum, Carduncello-Brachypodietum, Helictotricho-Seslerietum, Calamintho-Seselietum
and
Carici-Teucrietum.
Conclusions
: The combination of numerical methods allowed a consistent and more objective classification of grassland types in Navarre than previous approaches. At the association level, we could largely reproduce the units previously described with traditional phytosociological methods. By contrast, at higher syntaxonomic level, our analyses suggest significant modifications. Most importantly, a major part of the units traditionally included in the
Festuco-Ononidetea
seem to fall within the
Festuco-Brometea
. We could show that bryophytes and lichens are core elements of these grasslands and particularly the Mediterranean ones of
Lygeo-Stipetea
, both in terms of biodiversity and of diagnostic species. We conclude that the combination of our different numerical methods is promising for deriving more objective and reproducible delimitations of syntaxa in a hierarchical manner.
Taxonomic references
: Euro+Med (2006–2021) for vascular plants, Hodges et al. (2020) for bryophytes and The British Lichen Society (2021) for lichens, except for
Endocarpon loscosii, Heppia lutosa, Psora saviczii
and
P. vallesiaca
, which follow Nimis and Martellos (2021), and
Buellia zoharyi, Fulgensia poeltii, Lichenochora clauzadei
and
Toninia massata
, which follow Llimona et al. (2001).
Syntaxonomic reference
: Mucina et al. (2016), except for those syntaxa specifically treated here and given with authorities.
Abbreviations
: ANOVA = analysis of variance; EDGG = Eurasian Dry Grassland Group; NMDS: non-metric multidimensional scaling; TWINSPAN = Two-Way Indicator Species Analysis.
Se describe una nueva asociación vegetal, Erico terminalis-Schoenetum nigricantis (All. MolinioHoloschoenion vulgaris), dominada por Schoenus nigricans, Erica terminalis y E. erigena, que resulta ...endémica de las áreas termomediterráneas de las sierras de elevación media o baja del sur de la provincia de Valencia. Es un
juncal negro de alta densidad, pero florísticamente muy pobre, que crece en la base de balmas y roquedos calizos rezumantes, donde se acumulan tobas calcáreas y depósitos terrosos, que permanecen húmedos buena parte del año gracias a surgencias temporales de agua. Se aportan asimismo datos sobre la composición florística, comportamiento ecológico, distribución y relaciones de esta comunidad con otras de similar fisonomía. Paralelamente, se realiza la
corrección nomenclatural del matorral setabense Thymo piperellae-Helianthemetum rotundifolii Rivas Goday 1958 corr. Solanas & M.B. Crespo hoc. loc. Thymo piperellae-Helianthemetum mollis Rivas Goday 1958, nom. incorr., dado que el taxon que da nombre a la asociación es realmente Helianthemun rotundifolium y no H. molle o H. marifolium,como se ha indicado en ocasiones
A new endemic plant association, Erico terminalis-Schoenetum nigricantis (All.Molinio-Holoschoenion vulgaris), is described from the thermomediterranean areas of the low- or medium-elevation mountains of the southern parts of Valencia province, which is dominated by Schoenus nigricans, Erica terminalis and E. erigena. This is a dense but poorly characterised black-sedge community, occurring at the base of “balmas” and dripping limestone cliffs, where deposits of tufa or clay are formed which remain sodden during part of the year due to water emergence. Data on the floristic composition, ecology, distribution and sintaxonomic relationships of this habitat are also reported with regard to other similar communities. Furthermore, the nomenclatural correction Thymo piperellae-Helianthemetum rotundifolii Rivas Goday 1958 corr. Solanas & M.B. Crespo hoc. loc. Thymo piperellaeHelianthemetum mollis Rivas Goday 1958, nom. incorr. is stated, since the taxon used to name that Saetabensian scrub is indeed Helianthemun rotundifolium, neither H. molle nor H. marifolium as sometimes it was suggested.
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