Tom 20 (2021): Zeszyt 1 (June 2021)

Hacquetia is entering 20^th year and in editorial we are presenting history of journal in this period, statistics of authors diversity, geographical distribution of published papers and bibliometrics. We highlighted fruitfull collaboration with guest editorsc, the most cited articles and presented future goals.

Eight new localities of the rare, strictly protected macrophyte Vallisneria spiralis have been recorded during a comprehensive survey of water bodies in Croatia. One record is located in the Mediterranean Region, in Butoniga Reservoir, while the remaining records are from the Continental Region, the majority of them situated along the Kupa River. Vallisneria spiralis occurred in slightly basic and alkaline environments and in a wide range of nutrient availability. In Continental localities, the species was present within Myriophyllo-Nupharetum luteae of the alliance Nymphaeion-albae, while in Butoniga, it occurred within the vegetation of the alliance Potamogetonion. Prior to our research, the species was recorded in Croatia only twice, with the older record dating back to the 19^th century and the second from recent years, but neither one was confirmed in later surveys. The low number of records of V. spiralis, in spite of a wide-ranging search through hundreds of localities, confirmed the rare status of this species, although the reasons for such limited distribution remain unclear, especially bearing in mind that suitable aquatic habitats are quite widespread in the country.

Five new alien taxa are here recorded from Tunisia. Reported taxa (Livistona chinensis, Phoenix canariensis, P. reclinata, P. theophrasti and Washingtonia robusta) belong to the subfamily Coryphoideae (Arecaceae). Updated nomenclature, brief descriptions, general and national distributions are provided for each species. Livistona chinensis and Phoenix theophrasti are here reported for the first time in North Africa. Identification keys are also provided.

Sesuvium is a genus of 14 to 17 species of succulent plants, both annual and perennial, widely distributed in tropical and subtropical regions. The genus Sesuvium has not yet been studied in detail in the Southern Cone (Argentina, Southern Brazil, Chile, Paraguay and Uruguay), which has led to a misidentification of numerous specimens as S. portulacastrum. As part of the ongoing floristic, taxonomic and ecologic studies in Argentina, we revise the genus Sesuvium for the Southern Cone. This study is based on field investigation, examination of herbarium specimens, and revision of literature. The taxonomic treatments, maps of distribution, detailed descriptions, photographs, an illustration, a dichotomous key and a comparative table to differentiate the species of the genus Sesuvium occurring in the Southern Cone are presented. Finally, ecological, morphological, and taxonomic aspects of the species are discussed. The new combination of S. americanum (≡ Trianthema americanum Gillies ex Arn.; = S. verrucosum Raf.) is proposed. Lectotypes for three names are here designated (S. revolutifolium Vahl ex Willd.; S. revolutifolium Lam., and S. parviflorum DC.). Four species should be accepted for the Southern Cone: S. americanum, S. humifusum, S. mezianum and S. sessile. Furthermore, S. portulacastrum is excluded from the flora of the Southern Cone.

This is the first record of the liverwort Riccia atromarginata for the Western Balkans. It was found on conglomerate terraces in the city of Podgorica, Montenegro, at the confluence of the rivers Ribnica and Morača. The material from Montenegro as well as living samples from Tenerife, Gran Canaria and Cyprus served as a basis for a detailed description of the main characteristics of the species, on the basis of which Riccia atromarginata can be reliably identified. However, for some characteristics there is a clear variability.

In already known localities in the Julian Alps (Mangart, Malo Polje, Zeleno Jezero, Blehe under Šoštar) and in several new ones (Loška Koritnica, Bavh, Spodnji Lepoč, Mlinarica, Konjska planina, Mali Babanski Skedenj) we inventoried the stands along the subalpine-alpine springs and spring areas where Carex frigida frequently occurs as the predominant vascular plant. We classified them into the following associations: Saxifrago aizoidis-Caricetum ferrugineae, Caricetum davallianae s. lat., Ranunculo traunfellneri-Paederotetum luteae, Carici frigidae-Petasitetum albi (alliance Adenostylion alliariae) and Palustriello decipientis-Caricetum frigidae (alliance Cratoneurion). The latter two were described as new. Based on comparisons with similar communities along mountain springs we discussed the most appropriate classification of the latter into higher syntaxonomic units.

Vegetated walls are an important habitat for urban biodiversity. We conducted an analysis of the plant species that grow on the Elbasan, Albania fortress walls. Walls vary in age from 4^th to 21^st century, and in composition. On 71 walls we assessed 2787 plants of 35 species and recorded plant size, presence of flowers or fruits, height from the ground, crevice depth, wall aspect, wall age and composition, and distance to nearest opposing wall. Eleven species, two of which were ferns, composed 93.8% of the plants. The vast majority of plants flowered and fruited on the walls. Plant density ranged from 0.1–70 plants/m². Species distributions varied significantly based on height on the wall, crevice depth, aspect and distance to the opposing wall. These differences may be influenced by dispersal mechanisms, moisture, substrate composition, and other important environmental factors. For example, Antirrhinum majus was generally found high on south facing walls in deep cracks whereas Umbilicus rupestris was found lower on north facing walls in shallower cracks. It is important that older walls colonized by plants be maintained such that a native flora can persist where natural rocky features are lacking.

We studied the site ecology of Salvia brachyodon (Lamiaceae), a narrow endemic of the eastern Adriatic, which is now restricted to only three sites, using the sigmatistic method and numerical analyses. Four floristically and ecologically well-defined groups of stands, representing different syntaxa, were identified, corresponding to the sampling sites. The majority of stands represent dry eastern (sub)Mediterranean rocky grasslands at different successional stages towards (sub)Mediterranean forest vegetation. Compared to the evolutionary and ecologically closely related and sympatric S. officinalis, the morphologically easily distinguishable S. brachyodon differs in its flowering phenology and prefers relatively cooler, wetter, deeper and nutrient richer soils, which are developed on dolomite or dolomitic limestone at higher elevated sites. Despite its ability to cope with interspecific competition by means of clonal reproduction better than its congener, the populations are severely threatened by abandonment of traditional land use and by fires, making the species endangered (EN) according to IUCN criteria.

We present a summary of part of the phytogeographic results described in the author’s PhD thesis. In this case, we characterise and validate several syntaxa of subsaline meadows in the Trifolion squamosi nom. corr. alliance (class. Juncetea maritimi) in Catalonia (incl. NE Spain and SE France) and in other regions of the Western Mediterranean (N Algeria, Languedoc and Provence). In total, we study six syntaxa in geobotanical terms, based on synthetic tables and factor analyses of correspondence published previously in the thesis: one alliance (Trifolion squamosi), two associations and three subassociations (Agropyro-Trifolietum subass. typicum, subass. festucetosum comb. nova, subass. brachypodietosum nova; Festucetum arundinaceae).

The Žumberak and Samobor highlands are situated in the north-western part of Croatia where the characteristics of the Dinarides, the Alps and the Pannonian Plain meet. The greater part of the area is occupied by beech forests. The aim of the study was to determine the syntaxonomic affiliation of these forest communities, and to explore their floristic and main ecological features. Numerical analyses of floristic compositions were conducted on a data-set consisting of 144 new relevés and 99 relevés from the existing literature. Relevés were made following the standard Braun-Blanquet method. For descriptions of ecological conditions Ellenberg’s indicator values were used. Six plant associations and two subassociations of beech forests were established in Luzulo-Fagion and Aremonio-Fagion alliances. The higher altitudes of the studied area are occupied by ass. Cardamini savensi-Fagetum, whereas the lower altitudes are occupied by ass. Lamio orvalae-Fagetum and Hacquetio-Fagetum. Ass. Hacquetio-Fagetum spreads on southern slopes and ridges, whereas ass. Lamio orvalae-Fagetum occurs in ditches and on northern slopes. In the warmer habitats with shallow soils on a dolomite base ass. Ostryo-Fagetum occurred. A small part of the area is characterized by silicate substrate which is occupied by ass. Luzulo-Fagetum and Gentiano asclepiadeae-Fagetum.

This special issue is a collection of articles about the conservation, restoration and biodiversity of Palaearctic grasslands and was initiated by the Eurasian Dry Grassland Group at the 15th Eurasian Dry Grassland Conference (EDGC), held at Graz, Austria in 2019. The papers in this special issue cover a range of grassland habitats from montane dry grasslands to lowland sandy grasslands, feathergrass steppes and meadow steppes, and focus on the biodiversity values, conservation issues and restoration prospects of Palaearctic grasslands. We hope that the articles in this special issue will contribute to a better understanding of the ecology of grasslands and support their more effective conservation.

This report summarizes the activities and achievements of the Eurasian Dry Grassland Group (EDGG) from July 2019 to December 2020. During this period, Covid-19 allowed only one live event, the 14th EDGG Field Workshop to the alpine vegetation of Switzerland, organised ad hoc as a replacement for the cancelled Field Workshop in the Ukrainian steppes. The cancelled Eurasian Grassland Conference in Spain found a partial replacement in “Talk Grasslands!”, a series of online talks during winter 2020/2021. EDGG’s own diamond open access periodical, Palaearctic Grasslands, is a novel combination of scientific journal, photo magazine and member newsletter. With five issues during the reporting time it contributed much to EDGG’s attractiveness. EDGG edited four Special Features in international journals (Tuexenia, Hacquetia, Flora) and contributed 13 chapters on grasslands and shrublands of the Palaearctic biogeographic realm to the Encyclopedia of the world’s biomes. EDGG’s vegetation-plot database GrassPlot with multi-scale and multi-taxon diversity data of grasslands and other open habitats of the Palaearctic is now integrated into the EDGG website with the GrassPlot Diversity Explorer.

We report an exceptionally fast grassland recovery process from a karst plateau in SW Slovenia. Vegetation of old fields with different ages was sampled using a chronosequence of fields abandoned 1, 3, 6, 9, 13, 15 and 100 years ago. We prepared dendrogram dividing the data set into 9 clusters that were further analyzed: diagnostic species, ecological conditions and life forms were evaluated. The initial stage of succession was characterized by segetal weeds and indicated high levels of soil nutrients. The second stage was dominated by dense patches of perennial forbs (most of them ruderal species) preferring also high levels of soil nutrients. The third stage was dominated by caespitose hemicryptophyte grasses, many of them of sub-Mediterranean origin. The first two stages took 13 years and both could be considered as early successional stages developing on nutrient rich soils. These stages were switched to late successional stage characterized by seminatural grassland species. The quick succession can probably be attributed to the rich species pool of natural grassland flora, the small size and annual mowing of abandoned agricultural fields and the close proximity of seed sources.

Following the rediscovery after 200 years of Ablepharus kitaibelii fitzingeri in 2017, we carried out data collection its habitats regarding vegetation, microclimate, and soil on two prominent dolomite hills of the Eastern Bakony. Data collections were carried out in habitat mosaics (xerothermic forest edges on the plateaus, karst shrub forests in south-facing exposure, dry grasslands among forest patches on the plateaus, rocky grasslands in south-facing exposure) of three sampling blocks. Vegetation was examined by phytosociological relevés, microclimate from April to November continuously by TMS-2 dataloggers, and soil by laboratory analyses focused mainly on percentage of different fractions. According to our results a) shrub forests with a south-facing exposure provide a cooler microclimate with temperated fluctuation in the spring–early summer and late summer–early autumn periods; b) plateau grasslands and shrubs are characterised by looser soil structure. Based on our results, heterogeneous habitat character of forest–grassland mosaics of the Pannonicum can mitigate the expected negative effects of climate change on reptiles.

The aim of our study is to establish the determinant ecological factors that have the greatest differential impact on the distribution of meadow steppe plant communities of Western Podolia (Ukraine) on the base of a synphytoindication analysis. There were 8 study sites within the study area in the L’viv and Ivano-Frankivsk regions. To determine the coenotic affinity of the studied species, 48 relevés were analyzed. Numerical classification based on the Modified TWINSPAN algorithm divided the dataset into five clusters, which have been identified as the associations Pastinaco sativae-Arrhenatheretum elatioris, Geranio sanguinei-Trifolietum alpestris, Inuletum ensifoliae, Jurineo calcareae-Stipetum capillatae and Lembotropio nigricans-Potentilletum arenariae. The results of gradient analyses indicate that the distribution of meadow steppe communities in the Podolia Upland closely correlates with a number of climatic (thermoregime and continentality of climate) and especially edaphic (soil humidity, soil acidity and carbonate content) ecological factors.

Festucetum vaginatae Rapaics ex Soó 1929 em. Borhidi 1996 is a characteristic association of the calcareous sandy areas of the Pannonian basin; its dominant grass species is Festuca vaginata. Another typical species of these sandy areas is the newly discovered F. pseudovaginata. The question is whether F. pseudovaginata forms an independent coenotaxa? Our study proved that F. vaginata and F. pseudovaginata populations grow separately and compose different associations. Stands dominated by F. pseudovaginata had a higher species richness and harboured twice as many Festuco-Brometea species compared to the Festucetum vaginatae stands. Diagnostic species of the Festucetum pseudovaginatae association are Festuca pseudovaginata, Colchicum arenarium, Ephedra distachya, Koeleria majoriflora, and Astragalus onobrychis. The number of species, the density of the individuals, and the variability and diversity of the vegetation separated it from the Festucetum vaginatae association; thus, it can be considered an independent endemic association. Festucetum pseudovaginatae has its own differentiating and dominant species: Carex stenophylla, Cynodon dactylon, Eryngium campestre, Kochia laniflora.

Dry grassland ecosystems are highly fragmented in Ukraine and increasingly threatened from intensification of farming practices. Evaluation of the habitat conservation importance based on multitaxon studies allows for optimizing selection of priority sites. Botanical research of xerothermic habitats in the Kryvorizkyi Iron Ore Basin has been conducted since 2012, while spiders were investigated for the first time in 2017. In the four study sites, we recorded 265 vascular plant species (23 under protection) and 95 spider species (19 are rare). Both vegetation and spider communities of the site Zelena Gully are well preserved and rich in rare and threatened species (18 plant and 11 spider species), which confirms its value as a priority site of the Emerald Network. Chervona Gully and the Slate Rocks should be included in the network. Frequent fires and intensive grazing in Khrystoforova Gully affect the spider diversity, decreasing the number of specialist and rare species, while early flowering plants benefit from this disturbance. Nevertheless, its vegetation is poorer than in Zelena and Chervona gullies. Inclusion in the Emerald Network is critically important to the investigated sites, since expansion of mining activities is constantly threatening natural habitats in industrial regions.