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Halophytic localities in the Velké Němčice, Šakvice and Rakvice districts (A) Plácky 2020, (B) Štinkovka 2021, (C) Trkmanec-Rybníčky 2020. Photo credits: K. Chytrý (A), M. Chytrý (B), E. Šmerdová (C).
Source publication
Halophytic habitats are distinctive components of the landscape in southern Moravia, Czech Republic, and the Pulkau valley in northern Lower Austria. We provide a historical overview of their flora and vegetation since the early 19th century and describe the current state assessed in the field at all remaining sites in 2020. We summarized the histo...
Citations
... We studied one of the major saline areas in Europe, the Pannonian Basin and adjacent areas to the east. Its plains and endorheic basins host mosaics of saline grasslands, herb-dominated vegetation, and open vegetation dominated by highly specialized annual salt-adapted species that occur in extensive steppes with diverse microtopographical levels or on salt pans (Danihelka et al., 2022;Dítě et al., 2017;Eliáš et al., 2020;Molnár et al., 2008;Wendelberger, 1943). Given the dependence on stable, seasonally fluctuating groundwater and extensive grazing, halophytic vegetation in the region is vulnerable to land-use change Janssen et al., 2016) and of conservation concern (EU Habitats Directive;European Commission, 2013;Šefferová Stanová et al., 2008). ...
... We pooled three randomly placed samples into one soil sample per plot for laboratory analyses. We supplemented our field data with 76 plots of 10 m 2 sampled between 2010 and 2020 (Danihelka et al., 2022;Prokešová, 2013) and 177 plots of 12 to 16 m 2 sampled between 2005 and 2020 (Dítě & Dítě, unpublished). ...
... We analysed 236 topsoil samples from our fieldwork in 2021 and from Danihelka et al. (2022) in the Laboratory of Water, Sediment and Soil Chemistry in the Department of Botany and Zoology, Masaryk University. Soil samples were homogenized by sieving through a 2 mm mesh. ...
Aim
In salt-affected environments, salinity shapes ecosystem functions and species composition. Apart from salinity, however, we know little about how soil chemical factors affect plant species. We hypothesized that specific ions, most of which contribute to salinity, co-determine plant niche differentiation. We asked if the importance of ions differs for species with (halophytes) and without (associated species) physiological adaptations to saline soils.
Location
Carpatho-Pannonian region (Central and Eastern Europe).
Time period
2005–2021.
Major taxa studied
Vascular plants.
Methods
We recorded species occurrences and collected soil samples in 433 plots in saline habitats. We measured pH, salinity (electrical conductivity), and concentrations of Ca2+, K+, Mg2+, Na+, SO42− Cl−, CO32− and mineral nitrogen (mN) and calculated the sodium adsorption ratio (SAR). For 88 species, we fitted response curves with Huisman–Olff–Fresco (HOF) models. To study ions' effects on species composition and ions' variance, we compared unconstrained and constrained ordinations and performed a principal component analysis. We used random forests to analyse the importance of ions for individual species and created two-dimensional species niche plots for key ions.
Results
Ion concentration niches varied among species and did not necessarily correspond to soil salinity or alkalinity. We frequently observed monotonic, sigmoidal model responses, while skewed unimodal responses were rare. Ions explained a considerable proportion of species compositional variation. Particularly, Na+, SO42−, Cl−, and CO32− contributed to the ions' variance. Na+, followed by SO42−, Cl−, CO32−, Ca2+, Mg2+, and mN, was most important for the occurrence of individual species. Compared to associated species, Na+, SO42−, and mN were significantly less important for halophytes, whereas Cl− and CO32− played a significant role.
Main conclusions
We show that ion composition co-determines niche differentiation in saline soils, suggesting evolved physiological adaptations in halophytes. Our study calls for incorporating high-resolution data on soil ion composition in ecological research.
... Another habitat rarely considered as the main source of Amaranthaceae and Artemisia pollen is wetland vegetation consisting of nitrophilous annuals, such as Bidentetea tripartitae. This class of wetland vegetation occurs in landscapes affected by anthropogenic eutrophication due to periodic inundation, accompanied by the accumulation of salt, nutrients and nitrogen (Danihelka et al. 2022). The scattered distribution of Bidentetea tripartitae includes site Olbramovice in southern Moravia (Svobodová 1997), which was included in the current study. ...
Tracing human-vegetation interactions that occurred in the past has always been one of the key topics of paleoecology. Here we use the pollen and archaeological databases available for the Czech Republic to determine links between individual pollen taxa and archaeological data and search for the spatial scales of comparability. The datasets include 1,500 pollen samples and 65,000 archaeological components covering the period from 12,000 to 700 cal. BP , divided into time windows of 250 years. Spearman’s rank correlation was used to measure the link between pollen and archaeological data at different sites. Using generalized additive models for the whole dataset, we explained the variance of pollen by archaeologically registered human activities and by two environmental variables . The first was the overall trend for each taxon in the Holocene representing the long-term dynamics of the species, the second was the elevation of pollen sites. Both factors affect species representation over the whole period studied or/and the area and cannot be statistically separated from human-induced changes. Both decrease the indicative strength of anthropogenic pollen; however, elevation did so more than the Holocene trend, since past human activities and elevation are strongly correlated and account for the first main gradient. The pollen taxa with a positive correlation with the level of past human activity, indicated by all methods, are: Plantago lanceolata, Artemisia and Amaranthaceae, re-sprouting edible trees that tolerate fire and pruning (Quercus) and pioneer trees (Pinus). Probability indicating the presence or absence of archaeological evidence when pollen of these species is present or absent is high (0.56–0.76). However, explained variability by the full model is low (0.01–0.09). Fagus, Carpinus and Abies expand during the late-successional stages after human disturbance, therefore their relationships to past human activity are negative when considering a 250-year time window. Secale does not correlate at the level of individual sites due to its late appearance during the Holocene. We ascribe the weak relationship between archaeological data and pollen of Cerealia to inconsistent determinations. The radius of comparability of pollen and archaeological evidence is around tens of kilometres due to the spatial resolution of archaeology is the area of a parish, but lower for herbaceous plants (15–20 km) than for trees (30–40 km). This critical comparison delimits overlaps and gaps between widely-used assumptions and data-based evidence.
... In contrast, ecological restoration of extreme habitats created by natural disturbance or human activities, such as mining, may be followed by the rapid appearance of threatened specialists of the respective habitats. This trajectory of successional development was reported in several case studies of sandy grasslands (Olsson & Ödman 2014(Olsson & Ödman , Řehounková et al. 2021, halophytic vegetation (Danihelka et al. 2022), limestone quarries (Tropek et al. 2010), and fens (Ekrtová et al. 2018). However, this pattern is unlikely to be universal, as the dynamics of the establishment of threatened species can vary considerably depending on type of habitat. ...
Conservation strategies often assume that the total number of species at a specific location can be used as a proxy for other biodiversity dimensions, such as, the presence of rare and threatened species. However, the validity of this assumption remains unclear, particularly at the plot scale. Here, we used~17,000 vegetation plots sampled across the Czech Republic to examine the relationship between the occurrence of threatened plant species and species richness in temperate forest and grassland communities. For each individual species, the median, range, and skewness of species richness in the plots in which it occurred were used to define its distribution along the community species richness gradient. These parameters were then compared for threatened and non-threatened species. We also compared the observed values with those obtained under a null expectation to test whether threatened species occurred at random with respect to species richness. On average, threatened species occurred in species-richer plots than non-threatened species. In addition, threatened species assembled non-randomly with respect to species richness, as they occurred more often in species-richer forests but species-poorer grasslands than expected by chance. The occurrence pattern of threatened species in relation to species richness was driven by the species-pool sizes of individual habitats. Threatened species associated with low species richness were thus found in extreme habitats, such as bogs, salt marshes, peat forests, and alpine grasslands characterized by small species pools. In contrast, threatened species associated with high species richness were often found in subconti-nental semi-dry grasslands and dry thermophilous forests with large species pools. Threatened species also occurred over shorter species richness gradients and were more symmetrically distributed along these gradients than non-threatened species. These patterns may reflect a high habitat specialization of threatened species or strict requirements for habitat quality. We therefore suggest that species richness is a poor indicator of conservation value when comparing habitats and geographic regions. Targeting specific habitats and using the presence or percentage of threatened or specialized species as indicators may provide better assessment of conservation value.
... The subhalophytic vegetation growing around mineralized springs at tectonic breaks in the west of the Czech Republic (Toman 1976) was recently destroyed. Salt springs occur scattered in South Moravia (Vicherek 1973, Grulich 1987, Danihelka et al. 2022, in Slovakia (Spiš basin) in the Western Carpathians (Šmarda 1961(Šmarda , Dítě et al. 2004, in Poland near Krakow (Piernik 2012) and in Romania in the foothills of the Eastern Carpathians, where saline areas are associated with mineralrich springs and mud volcanoes (Dítě et al. 2022a). ...
There is a long tradition in Europe of assigning ecological indicator values to plants and using these values in ecological research. A special case is that of the salt-tolerant species.
Saline soils are extremely heterogeneous and their physical and chemical properties vary significantly with microrelief and between alternating dry/wet seasons. The complexity of such soils suggests using salt indicator values. This study resulted in the firstmulti-country database of vascular plants occurring in inland salt marshes and on salt steppes in temperate Europe based on expert revision of the literature and field experience. The inventory of the 190 salt-tolerant species was carried out according to their quantitative representation in saline and non-saline habitats. These species were each classified into one of three categories of salt tolerance (obligate halophytes, facultative halophytes, accessory/associated species) assigned salt numbers on
a nine-point scale reflecting their individual preference for soil salinity based on their calculated halophytic value. Saline soils are reliably indicated by the presence of obligate halophytes; these specialists grow exclusively in natural saline habitats. Only 45 species are assigned to this group, while 61 species make up the group of facultative halophytes and 84 are accessory species with a wide ecological niche, occurring more or less accidentally in saline habitats. Their number is likely to increase since every plant (non-halophyte) recorded in a saline habitat can be considered to be an accessory species. The obtained salt numbers showed a close consistency with the recently used salinity indicator values estimated by Ellenberg, Borhidi and Breckle; in terms of categories of salt tolerance, only slight differences were detected.
... The introduction of freshwater thus promoted the stability of the plant communities in the coastal wetlands invaded by S. alterniflora. Environmental factors, particularly soil salinity, significantly influence the distribution of vegetation (Amores et al., 2013;Telesh et al., 2013;Archer et al., 2021;Danihelka et al., 2022). Because our investigations did not account for environmental indicators such as soil, this study did not analyze the environmental impact on different vegetation communities. ...
Plant invasions in coastal wetlands lead to the degradation of native vegetation; the introduction of freshwater in coastal wetlands would prevent the spread of invasive plants and facilitate the restoration of native vegetation. In this study, we evaluated the effects of freshwater on plant communities in the coastal wetlands of Yancheng, China, invaded by Spartina alterniflora Loisel. Two field investigations were conducted in 2008 and 2018 before and after the introduction of freshwater (started in 2011). The characteristics of plant communities were subjected to hierarchical cluster analysis and compared using several diversity indices. In addition, differences in habitat community composition and interspecific relationships of dominant species were analyzed. The results showed that S. alterniflora reduced the overall species diversity in the region. Plant species diversity increased after freshwater was introduced into the study site when compared to the areas without freshwater introduction. The introduction of freshwater caused a shift often changes in the interspecific relationships between Suaeda salsa (L.) Pall. and other species. The intensified invasion of S. alterniflora changed the interspecific relationship of native halophytes from negative to positive. Although freshwater effectively inhibited further invasion of S. alterniflora, it also increased the risk of expansion of the glycophytes in the community. The results of this study highlight the need for early intervention for restoration of coastal wetlands, preservation of biodiversity, and management of plant resources.
... Classification of the south European coastal part of salt marsh communities also already exists, based on Croatian data (Dítě et al., 2019). Danihelka et al. (2022) presented halophytic vegetation of southern Moravia and northern Lower Austria. However, there is still a gap in the current classification system for inland salt-marsh vegetation across whole temperate Europe, although some of it was analyzed on the basis of data from the North German Plain (Dítě et al., 2022). ...
... Currently association is rather not listed in southern or western Europe, incl. in Romania (Dítě et al., 2021). This may be related to the local extinction of T. maritima and G. maritima (Danihelka et al., 2022), which was earlier noted also in inland positions of western Europe. The Agrostio stoloniferae-Juncetum ranarii association was recorded in our data set only on inland salt marshes in the United Kingdom and France. ...
Inland salt marshes are recognized as habitats of unique and valuable vegetation at the European scale. There is still a lack of generalization regarding its vegetation syntaxonomy and environmental requirements, which is needed for its effective protection. To falsify our hypothesis about vegetation dependence on environmental requirements we aimed at description of the syntaxonomical units present in temperate European inland salt marshes and identification of their main environmental drivers. In our work we focused on the vegetation from the northern part of temperate salt marshes to limit confusion related to the geographical ranges of species. We collected the database of 968 vegetation plots from different European countries and applied the Cocktail method to analyze the data. Based on results, expert knowledge, existing syntaxonomical classifications and information from the literature, we identified diagnostic, constant and dominant species for individual syntaxonomical units. Then, we compiled maps of the vegetation unit distribution, and identified the most important environmental factors for the analyzed vegetation using statistical and multivariate methods, including canonical variate analysis. We classified the analyzed vegetation into nine classes, including two typical for salt-marsh vegetation – the Therosalicornietea and Festuco-Puccinellietea. Within these two classes, we distinguished two alliances and a total of five associations. The classes differs the most in terms of species preferences to salinity, soil moisture, light availability and soil nitrogen content. In addition salt marsh associations differ also by soil reaction and soil organic matter content. This provides direct implications for salt marsh sustainable management.
... Im Pannonikum außerhalb des Seewinkels stark gefährdet.Oft nur mehr sehr kleine Populationen. Außerhalb des Neusiedlersee-Gebiets und des Leithabodens heute fast überall ausgestorben, mit Ausnahme bei Zwingendorf im Pulkautal (Niederösterreich), wo die Art 2020 das letzte Mal beobachtet wurde(Danihelka & al. 2022).Außerhalb des Pannonikums und seiner Randlagen unbeständig. Ehemals an Ruderal-und Segetalstandorten des Pannonikums, seit jeher selten. ...
Red list of Austrian vascular plants.
... Im Pannonikum außerhalb des Seewinkels stark gefährdet.Oft nur mehr sehr kleine Populationen. Außerhalb des Neusiedlersee-Gebiets und des Leithabodens heute fast überall ausgestorben, mit Ausnahme bei Zwingendorf im Pulkautal (Niederösterreich), wo die Art 2020 das letzte Mal beobachtet wurde(Danihelka & al. 2022).Außerhalb des Pannonikums und seiner Randlagen unbeständig. Ehemals an Ruderal-und Segetalstandorten des Pannonikums, seit jeher selten. ...
Alien plant invasions have been systematically studied for more than half a century and we already have extensive scientific evidence of their negative role in the current biodiversity decline. Here we aim to draw attention to expansive plants, i.e. native plant species that exhibit similar ecological behaviour to invasive alien plants, being promoted by recent environmental changes. Some of them can also have various negative impacts on native plant communities and ecosystems. However, they have been much less studied than alien species. Our goal was to create an up-to-date catalogue of expansive species (including aggregates or subspecies where needed) in the Czech Republic, compare their functional traits and ecological strategies with non-expansive native species and provide a list of regions and habitats where they spread. We conducted a questionnaire survey, asking local experts to evaluate the expansive character of preselected species in 17 regions and 27 broadly defined habitat types (66 regional ass
In Bulgaria, Galatella cana was found only once near Lom town (Montana District) in 1892 and it had remained with an unconfirmed status ever since. A new locality, in the Thracian Lowland floristic region , was discovered in 2023, based on some misidentified specimens in the historical collection of Václav Stříbrný. The aim of the present article is to confirm the occurrence of G. cana in Bulgarian flora and to provide data of its only surviving population. An updated dichotomous key to the Bulgarian representatives of the genus Galatella is also presented.
