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  • Water contraction drives stronger the formation of diatom assemblages in stream than human induced microhabitat-variability
    211-228
    Views:
    323

    Today, climate change, together with other anthropogenic influences is considered as a major threat affecting aquatic ecosystems in several ways. Here, altering water contraction (standing and flowing phases) and human-induced habitat variability (natural and artificial stream sections) were studied as modifying factors driving community changes in benthic diatom assemblages of a Hungarian small lowland stream (Létai-ér). We assumed notable compositional differences between phases and habitats, but we expected these differences to decrease with drying. Moreover, lower diversity was hypothesized in assemblages of both artificial section and flowing phase. While taxonomic composition did not reveal significant differences between the sections, well pronounced compositional changes were found between phases. Surprisingly, no significant diversity changes were observed during water contraction. Compared to the natural microhabitat, however, artificial stream section was found to maintain more diverse diatom community. These results emphasize that modification effects of climate change induced hydrological extremes can lead to remarkable compositional changes in benthic algal assemblages even on a short time scale, that must be taken into account in both water management and nature conservation strategies.

  • Contributions to the algal flora of a recently-formed peat moss bog near Kőszeg (W Hungary)
    113–130
    Views:
    549

    The Alsó-erdő peat bog near Kőszeg has undergone a significant transformation since its first mention in the literature. In addition to the original single patch, a smaller one appeared a few decades later. The process did not stop and a third unit, discussed here, was formed. The succession of its macrovegetation towards the typical peat moss association started slowly but surely, due to balanced water regime and other optimal environmental conditions. The process is more advanced for the algal vegetation, which shows the characteristics of peat bogs already. The high species diversity found makes the habitat highly valuable itself. Although a special, unique algal species has not been found in previous studies, 27 Desmidiales taxa listed as endangered occur sometimes with high density and make the habitat even more valuable. Based on our results, the area deserves special attention both from the habitat conservation and research point of view. At the same time, its further monitoring can provide crucial information for exploring and understanding the succession of similar habitats, and thereby for their more efficient protection.

  • New species and changes in the bryophyte flora of the Mecsek valleys (Hungary)
    157–176
    Views:
    245

    The paper discusses the bryophyte flora of 77 sites in the Mecsek Mountains, mainly in deeper valleys. It includes species that are new to the area’s flora and/or endangered in Hungary, as well as mosses that have become more widespread or locally abundant compared to data from 1968 and 1983. The names of the locations, their geographical centers (centroids), and the grid unit IDs of the Hungarian Flora Mapping Programme (HFMP), where the sites are located, are listed and refer­enced according to their number in the list. Some of the species are national rarities, such as Scleropo­dium touretii, newly recorded in the Mecsek in 2023. Its second known occurrence in Hungary is re­ported in the Enumeration. We detail the occurrences of several species new to South Transdanubia, including Dicranum spurium, Diplophyllum albicans, Hypnum jutlandicum, Isothecium myosuroides, Kindbergia praelonga, Rhynchostegiella curviseta, Riccardia palmata, and Sciuro-hypnum plumosum. Additionally, species newly recorded from the Mecsek Mountains include Fontinalis antipyretica, Lepto­don smithii, Plagiomnium ellipticum, Pseudocampylium radicale, and Tortula brevissima. For two taxa, we present data of importance not only for the Mecsek, but also for the North-Hungarian Mts: Riccardia palmata, new for the Tornai-karszt, and Dicranum spurium, for which we confirm a very old record in the Zemplén Mts. We also note the widespread, sometimes massive occurrence of some aquatic and subaquatic mosses, e.g. Rhynchostegiella teneriffae, Hygrohypnum luridum, which have been recorded only once in the mountains in the last 50 years. The taxonomically uncertain Hygroamblystegium fluvia­tile with similar habitat requirements can now be found widely throughout the mountains. New popu­lations of Palustriella commutata, considered endangered and declining in the country, have been found in the Mecsek. The expansion of (sub-)aquatic species is particularly surprising in the light of recent hydroecological studies indicating that the streams in the Mecsek are drying up. The situation is similar regarding Rhynchostegium rotundifolium, previously thought to be a Tilio-Acerion (slope and ravine forest) species, which is legally protected in Hungary and only had one record from the Mecsek in the last century. This forest species is now found in peri-urban, sub-urban, slightly to moderately disturbed and secondary habitats throughout the mountains. Similar to its preference in Germany, outside of semi-natural habitats it occurs mainly on built structures in forest edges, ruins, abandoned mine sites, often in stands mixed with black locust and contaminated with litter. Microeurhynchium pumilum, which prefers sub-Mediterranean and sub-Atlantic climate, shady and humid habitats, has become one of the most widespread and abundant forest bryophytes in the Mecsek, in contrast to its few records 60 years ago. Half (50%) of the new mosses in the flora of the Mecsek can be connected to the cooler bore­al biome, while 21% is associated with the milder Mediterranean-Atlantic biome. The average of MAT (mean annual daily mean air temperatures averaged over one year) and MAP (accumulated precipita­tion amount over one year) of the 14 new species according to BET (Bryophytes of Europe Traits) indi­cates areas with much lower temperatures (7.7°C) than in Hungary, but with precipitation conditions (749 mm) similar to those in the Mecsek. The vast majority of the new species are extremely rare in Hungary, and are inconsistent with current climate warming trends. In contrast to the mosses with striking increase in records, the detection of new species is likely due to chance, in addition to system­atic research at finer spatial scales, rather than to local expansion of the species. However, in the case of expanding and abundant species, it is still an open question whether their dynamics compared to 40-60 year old references are apparent or real: the result of sampling bias in previous surveys or a conse­quence of climate change. In any case, the abundance of the above mentioned bryophytes in the Mecsek is not consistent with their current Hungarian Red List threat classification, and this cannot be attribut­ed to changes in definitions since 2010. The detected distribution and abundance, as well as the in­crease in the number of new species in the country within a decade, highlights the need for an updated Red List of Hungarian bryophytes.

  • Distribution of Calamagrostis stricta (Timm) Koeler in the Southern Nyírség (E Hungary)
    188-196
    Views:
    331

    This study presents the current distribution of narrow small-reed (Calamagrostis stricta (Timm) Koeler) in the southern part of Nyírség (E Hungary). Beyond the efforts to confirm previously known occurrences, a high number of potential habitats were surveyed. Field work was carried out from late autumn to early spring taking advantage of the better perceptibility of dry foliage. The species was detected in 43 localities inside the boundary of 15 settlements, which considerably exceeded our expectations. Although most of the populations were quite small, in some cases their extent reached over 1000 m².  Populations around the settlements of Penészlek, Fülöp and Nyírábrány were the most frequent and the largest in size. The endangered status of the species is caused by the insufficient water supply of suitable habitats in the region. Besides habitat change, desiccation can also amplify the effect of anthropogenic disturbances (e.g. ploughing, fishpond development), which poses a further threat to populations.

  • Disappearing botanical and cultural heritage of wooden headboard-graveyards in Eastern-Hungary and Transylvania (Romania)
    51-64
    Views:
    537

    Degradation or disappearance of natural habitats are global phenomena nowadays, hence the role of small and secondary (seminatural) habitats like cemeteries in preserving natural values are more and more appreciated. The botanical values and burial customs were examined in a total of 51 graveyards in three different regions of Hungary and Romania (10, 19 and 22 graveyards in the North Hungarian Mountains, the Great Hungarian Plain and Transylvania, respectively). Altogether 25 in Hungary legally protected plant species were found, 1.5 protected species per graveyard on average. As we observed, traditional burials with wooden headboards are rapidly superseded by modern burial customs. Based on our non-representative poll (n=102), 90% of citizens on average are satisfied with current conditions in Hungarian graveyards. A two-thirds majority of respondents would prefer more frequent lawn-mowing in graveyards. 75% of respondents prefer modern tombs to traditional graves. Disappearance of old burial customs characterised by the use of wooden headboards (and the simultaneous change in traditional, habitat-friendly practices in graveyards) means not only a loss of cultural values, but threatens the natural biodiversity of graveyards as well.

  • Data to the flora of Sopron Hills and its foreground
    239-242
    Views:
    403

    The present study reports additional records to the flora of Sopron Hills and Sopron Basin. The records were collected during our field surveys between 2010 and 2014 and contain occurrence data of 19 vascular plant taxa. The genus Orobanche is represented by 5 species. Two taxa are new for the flora of Sopron Hills (Amaranthus blitoides, Orobanche teucrii), others are interesting because of their old or uncertain indication (e.g. Dianthus superbus, Myosotis sparsiflora, Orobanche lutea, Orobanche purpurea).

  • Notes to the vascular flora of Sopron Mountains and its foreground
    187–194
    Views:
    660

    Records of 26 vascular plant species from the territory of Sopron Mountains (16 species) and Sopron Basin (11 species) are presented. Our field works (between 2014 and 2020) focused on some localities at the eastern and southern parts of the region. Tetragonolobus maritimus is new for the Sopron Mts, whereas Ajuga chamaepithys and Lycopsis arvensis are new for the Hungarian part of the hills. Some protected plants like Agrostemma githago, Gentianopsis ciliata and Sesleria uliginosa were rediscovered in the region. Comments about all species and their local chorology are added. A remarkable degradation process of bogs around Harka village, caused mainly by insufficient water supply of meadows, was observed. The spread of occurrences of several naturalized weed such as Aegilops cylindrica, Galium parisiense, Geranium rotundifolium, Kochia scoparia, Lepidium virginicum, Oenothera salicifolia, Sagina apetala subsp. apetala and Verbascum lychnitis was noticed. The most surprising observations refer to Galium parisiense; the spread of the species by transport had no precedent in Hungary before.

  • The degradation of hygrophilous plant associations of the Nyárjas Lake (E Hungary)
    63–77
    Views:
    228

    The Nyárjas Lake (located near Kállósemjén, East Hungary) was one of the most typical bogs in the Nyírség until the early 1980’s. Most of its area was covered by the association of Carici-Menyanthetum. The number of species characteristic to the mentioned association was generally high. As the climate became drier, hotter and were characterised by higher magnitude of extremities, the water coverage became no longer as permanent. This resulted that the Menyanthes trifoliata and Listera ovata became extinct by 2000. Lemno-Potamea species were not found after 2010. Bidentetalia, Calystegietalia, Chenopodietea and Secalietea species became more prevalent, particularly in drier periods, and locations where Carici-Menyanthetum used to be characteristic. Cirsium arvense in the mid-1990’s and that of Urtica dioica in the mid-2010’s became dramatically abundant. Both the number and coverage of species indicating habitat degradation have increased. The composition of wet meadow plant associations shifted towards the drier Arrhenatheretea. A moderate revitalisation of wetland associations was, however, observed coinciding years with higher precipitation.