Evidence for the existence of nitrile selenides, potential 1,3-dipolarophiles in cycloaddition reactions, has been provided by direct spectroscopic methods. The parent nitrile selenide, selenofulminic acid (HCNSe), and its methyl and cyano derivatives have been photolytically generated in an inert solid argon matrix from 1,2,5-selenadiazoles by 280, 254, and 313 nm UV irradiation, respectively, and studied by ultraviolet spectroscopy and mid-infrared spectroscopy. Ground-state geometries have been obtained from quantum-chemical calculations at the CCSD(T)/aug-cc-pVTZ level. Nitrile selenides are predicted to be linear with a relatively weak N-Se bond.
Semi-natural grasslands were previously established through traditional land use and maintained by active management, but their extension nowadays is declining rapidly, particularly in areas that also have tourism potential. In parallel, the conservation value of the remaining areas is increasing. The shore of Lake Balaton is a particularly good example, as Lake Balaton is an area highly affected by tourism, yet there have been valuable habitats able to survive and provide refuge for many vulnerable, protected species. Fortunately, we have reliable information about the vegetation of the area from two decades ago. Comparing these data with our recent surveys we investigated the changes in habitats and the distribution of protected plant species in connection with the active conservation treatments such as grazing or cutting. Our results show that in areas where treatments are still ongoing, protected plant species are more likely to survive, or even other species can appear, which is in clear contrast with conditions experienced in abandoned areas, where at least seven protected species have disappeared. According to our results, minor, but appropriately chosen and well-executed management interventions, can help in the long-term maintenance of species-rich habitats and improving the conservation status of threatened species.
Üde és nedves réttársulásaink átalakulása, elszegényedése a hagyományos gyepkezelések felhagyása, valamint a lecsapolások és a klímaváltozás miatt országszerte általános probléma. A Batyki-láprét (120 ha) természetességi állapotát és fajkészletét tekintve kiemelkedik Nyugat-Magyarország megmaradt rétkomplexumai közül. Munkánk célja e terület kutatástörténeti előzményeinek összefoglalása, valamint aktuális állapotának, védett és ritka edényes növényfajainak felmérése volt. A terepi felmérések 2019 és 2021 között történtek, melynek során a védett növényfajok egyedszámát is rögzítettük. A kutatástörténet leírásához az irodalmi forrásokon túl a Magyar Természettudományi Múzeum Növénytára herbáriumának (BP) a területre vonatkozó lapjait is kikerestük. Vizsgálataink során 40 védett faj recens előfordulását dokumentáltuk, ezek között nyolc faj új a területre (Cardamine amara, Carex umbrosa, Cephalanthera damasonium, Eleocharis uniglumis, Dryopteris carthusiana, Epipactis tallosii, Leucojum vernum, Neottia nidus-avis), és négy olyan van, amit 1955 óta nem jeleztek innen (Carex appropinquata, C. davalliana, Juncus alpinoarticulatus, Thelypteris palustris). A legnagyobb egyedszámban (> 500 000 hajtás) az Iris sibirica, valamint (> 50 000 hajtás) a Veratrum album és az Ophioglossum vulgatum fordult elő. Egyes tipikus lápréti fajok populációmérete riasztóan alacsony (Carex appropinquata, C. davalliana, Parnassia palustris), jónéhány korábban jelzett faj pedig nem került elő (Eriophorum angustifolium, E. latifolium, Menyanthes trifoliata, Pedicularis palustris, Ranunculus lingua). Eredményeink megerősítik a Batyki-láprét kiemelkedő botanikai és természetvédelmi jelentőségét, de rámutatnak a növényzet átalakulásának tendenciájára és a terület kiszáradására is, ami alapján sürgető feladat a vízellátás javítása, valamint a megfelelő természetvédelmi kezelés kialakítása az értékek megőrzése érdekében.
Fritillaria meleagris is an endangered Eurasian species with declining populations in most of its distribution area. The signifi cance of the present study is to provide details for improving methods, how age-state structure can be identifi ed in a population. This could help finding the appropriate way of site-management where this species occurs. We investigated two F. meleagris populations in the western part of Hungary (Gyékényes, Tüskeszentpéter). We grouped the recorded plants into five age-state categories: dormant, juvenile, subadult, vegetative- and reproductive adult. We investigated diff erent plant traits such as plant height, number of leaves, leaf width and leaf length. The relative frequencies of leaf numbers differed signifi cantly between the two sites each year. Generally, the majority of the flowering plants had 5-6 leaves at both sites. Only plant height was positively related to plant reproductive success, but there were no clear trends in leaf width and leaf length. There are considerable diff erences in age-state ratios between our sampling sites. The proportion of reproductive plants was noticeably higher in both years in Tüskeszentpéter. Transition into dormant state was regular from all age groups at both sites.
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