Zmiany we florze zbiorowisk leśnych rezerwatu "Uroczysko Obiszów" (Wzgórza Dalkowskie) w latach 1973–1998

Changes in the flora of the forest communities of the “Uroczysko Obiszów” reserve (Wzgórza Dalkowskie, Lower Silesia) in 1973–1998. Fragmenta Floristica et Geobotanica Polonica 10: 119–130. Kraków. PL ISSN 1640 629X. ABSTRACT: The paper discusses changes in the flora of the forest communities of the “Uroczysko Obiszów” reserve on the hills of Wzgórza Dalkowskie (Wał Trzebnicki, Lower Silesia) which occurred in 1973–1998. During this time many species were vanishing. This group is represented mostly by plants of meadows and streams as well as thermophilous and synanthropic ones, which are replaced by new forest species. The forest communities have undergone substantial changes. Moist oak hornbeam forests (Galio Carpinetum stachyetosum) occurring in the reserve have got transformed into typical (Galio Carpinetum typicum), which have later turned into dry forms. The alder forest (Fraxino Alnetum) has lost over 50% of its plant composition since 1988. Its species diversity has declined with a simultaneous increase in the percentage and area coverage of several rush plants. Changes in the tree stand composition of the two communities are also observed.