Oak-hornbeam forests of central Europe

Abstract

Csiky J., Onyshchenko V. & Chytrý M. (2020) Oak-hornbeam forests in central Europe: a formalized classification and syntaxonomic revision. -Preslia 92: 1-34Oak-hornbeam forests (order Carpinetalia) are a widespread vegetation type in central Europe. As vegetation ecologists focused on them since the pioneering times of vegetation research, many syntaxonomic units are described. However, classification systems used in various central-European countries suffer from inconsistencies and overlaps of the concepts of particular associations. Currently there is no consistent syntaxonomic system based on numerical analysis of vegetation plots that would be valid for the whole of central Europe. Therefore, the main goal of this study is to provide a revised syntaxonomic system of oak-hornbeam forests across central Europe, develop formal definitions of the associations and include these definitions in a classification expert system. We recognized 13 associations, 9 from the alliance Carpinion betuli (central-European oakhornbeam forests) and four from the alliance Erythronio-Carpinion (Illyrian and northern Italian oak-hornbeam forests). We prepared an expert system that classified 55% of the relevés in a central-European oak-hornbeam forest dataset (n = 6212) at the association level. To stabilize the Carpinion betuli association names, we selected nomenclatural type relevés for associations that have not been typified so far. In addition, two association names (Poo chaixii-Carpinetum and Pseudostellario-Carpinetum) were validated. Ordination revealed the main drivers of species diversity in these forests, including a complex gradient of soil moisture, nutrient availability and geographical position (mainly latitude). Among the climate variables, annual temperature amplitude and mean annual temperature were most closely correlated with species composition. K e y w o r d s: Carpinetalia betuli, Carpinion betuli, classification expert system, Erythronio-Carpinion, formalized vegetation classification, syntaxonomy, temperate broad-leaved deciduous forests

Climate warming-induced replacement of mesic beech by thermophilic oak forests will reduce the carbon storage potential in aboveground biomass and soil

“…At its southern and south-eastern distribution limits, European beech most likely is limited by summer droughts and heat (Czúcz et al, 2011;Fang and Lechowicz, 2006), and its occurrence is restricted to the humid montane belt of the mountains (Coldea et al, 2015;Horvat et al 1974), avoiding the drier and hotter lowland regions. Here, beech forests are replaced by oak-rich sub-Mediterranean forest communities of the Quercetalia pubescenti-petraeae (thermophilic mixed oak forests) and Carpinetalia betuli (oak-hornbeam forests) orders (Czúcz et al, 2011;Novák et al, 2020). With the recent increase in summer temperatures, VPD and the frequency of heat waves (Barriopedro et al, 2011;Schär et al, 2004), and regionally decreasing summer precipitation (Caloiero et al, 2018;Schönwiese and Janoschitz, 2008) , it is predicted that the climate will become less favourable for beech not only in southern and south-eastern Europe but also in parts of its Central European distribution range (Dolos et al, 2016;Garamszegi et al, 2020;Mette et al, 2013;Walthert et al, 2020).…”

Classification of European oak–hornbeam forests and related vegetation types

“…OHFs are of key importance for biodiversity conservation because they serve as refugia for nemoral biota, especially in largely deforested lowlands (Vera, 2000; Kolb & Diekmann, 2004; Stefańska‐Krzaczek et al, 2016; Chytrý et al, 2019). They harbour numerous narrow‐range (limited to <20% of the study region, typically <10%) and relict forest plant species (Coldea, 2015; Novák et al, 2019, Novák, Willner et al, 2020; Gholizadeh et al, 2020) as well as rare semi‐shade species (Garbarino & Bergmeier, 2014; Miklín & Čížek, 2016; Kiedrzyński et al, 2017). They are classified as near threatened (NT) for EU28 and EU28+ countries, as their abiotic and biotic quality has decreased significantly over the last 50 years (Janssen et al, 2016).…”

“…More recent studies have focused on relatively understudied regions in Euxinia, the Caucasus and northern Iran (Çoban & Willner, 2018; Novák et al, 2019, Novák, Zukal et al, 2020; Gholizadeh et al, 2020). Modern overviews of OHF diversity across large parts of Europe appeared in the last two decades (Onyshchenko, 2009; Košir et al, 2013; Novák, Willner et al, 2020). In EVC (Mucina et al, 2016), OHFs comprise 10 primarily biogeographically defined alliances.…”

“…Oak–hornbeam forests and related vegetation types (OHFs; phytosociological orders Carpinetalia betuli and Lathyro‐Carpinetalia caucasicae in Mucina et al, 2016 and Gholizadeh et al, 2020) represent a significant part of European mesophilous broad‐leaved forest diversity (Neuhäusl, 1977; Bohn et al, 2000–2003; Košir et al, 2013; Mucina et al, 2016; Novák, Willner et al, 2020). They are estimated to potentially cover one‐tenth of Europe and are considered zonal vegetation, occurring mainly at low elevations throughout much of its temperate region (Bohn et al, 2000–2003; Figure 1).…”

Phytosociological Analysis of Natural and Artificial Pine Forests of the Class Vaccinio-Piceetea Br.-Bl. in Br.-Bl. et al. 1939 in the Sudetes and Their Foreland (Bohemian Massif, Central Europe)

“…The situation may have changed with both the emergence of new analytical tools based on numerical methods and the access to international databases allowing direct comparisons of communities from different geographical regions [17,18]. Consequently, traditional classification systems of forest communities in Central Europe have started to modify quickly, and many of the syntaxonomic units described from individual countries have been downgraded or renamed to synonyms, e.g., [19][20][21][22]. The final framework for the division into higher units (up to the level of alliance) is provided by the study of Mucina et al [23], to which the national classification systems should be gradually adapted.…”