BevezetésKorábban megjelent tanulmányunkban Magyarország különböző tájairól (Dél-Dunántúl, Duna-Tisza köze és Tiszántúl) közültünk előfordulási adatokat ritka vagy különleges élőhelyen előforduló növényfajokról. Sok esetben cönológiai felvételt is készítet-tünk a fajok élőhely-preferenciájának alaposabb megismeréséhez. Jelen tanulmányban ugyanezeket a szempontokat tartottuk szem előtt: csak olyan fajok adatait közöljük, melyek ritkaságuk vagy váratlan helyen történő megjelenésük miatt lehetnek érdekesek.A Maros menti területek természetközeli és másodlagos élőhelyeinek 2014 és 2015 kö-zötti kutatása újabb eredményeket hozott. A terepi mintavételezések elsősorban a vonalas létesítmények (folyók töltései és vasúti töltések) növényzetére, valamint a szikes élőhelyek (cickórós puszták, szikes mocsarak és szikes rétek) növényzetére koncentrálódtak.

Hydrological background of the dune slack vegetation in the Kiskunság In the southern Kiskunság the natural vegetation (sand steppe, fen meadow, fen or marsh and alkali vegetation) survived in the dune slack meadows (DSM). The vegetation of these meadows are species rich, and has high natural value. The main goal of this study is to reveal the hydrological backgrounds in order to help conservation of the natural values. Two DSM was investigated (MM and CS site): vegetation was sampled, observation wells were planted, and data of other wells in similar position were used to describe the hydrological background of the vegetation. The characteristic groundwater level of the same vegetation type in the relatively wet 2005 year was higher in MM site, than in the CS site. We suppose, that this is a consequence of the earlier vegetation change because of the strong decrease of groundwater level in the region of MM site. The model of hydraulic flow system showed that the DSMs are situated in hydraulic discharge zones. We suppose, that an upward flow plays an important role in development of alkali vegetation in the CS site. Cross-correlation coefficient between groundwater and previous precipitation indicated a quick infiltration of rainwater into the soil, and a pressure front of the groundwater stream reaching the area of well after 22-23 days after rainfall. The quick and strong regional hydrological changes, especially the decrease of groundwater level would endanger this valuable vegetation, but certain resistance and plasticity of it is rather possible.

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Data to the flora and vegetation of Hungary III.

Aim:We evaluated stands of the invasive grass, Sporobolus cryptandrus in its native North American range and its non-native European range, where it is a recent invader.Our aim was to reveal how the species' increasing abundance affects functional diversity and the ecosystem service-provisioning capacities of plant communities in both ranges.Location: Sand grasslands in the Kiskunság, Hungary and in Montana, USA.Methods: All vascular plant species and their relative abundances were recorded in a stratified random manner in 1 m × 1 m plots in each range, using the following cover categories of Sporobolus as strata: 1%-25%, 26%-50%, 50%-75%, and 75%-100%.The functional characteristics of the plant communities in the two continents were compared. We performed comparisons of the communities both with and without including Sporobolus.Results: Increasing Sporobolus cover resulted in a lower functional diversity and species richness, reduced average specific leaf area and increased the height of whole plant communities in both ranges but these effects were significantly stronger in the non-native stands. Sporobolus also negatively affected the cover of insect-pollinated plant species and the proportion of native perennials, switching the rest of the community from perennial-dominated to annual-dominated. In plant communities without Sporobolus, increasing Sporobolus cover led to a higher specific leaf area and seed mass in both ranges, but average height was decreasing along the Sporobolus abundance gradient in the native range, whereas it was increasing in the non-native range. Conclusions:The spread of Sporobolus, away from its native range, leads to the impoverishment of host communities and compromises the biomass and floral resourceprovisioning capacity of the vegetation to higher trophic levels. Tackling the spread of this new invader should therefore be a priority task.