Due to changes in the global climate, isolated alpine sites have become one of the most vulnerable habitats worldwide. The indigenous fauna in these habitats is threatened by an invasive species, dwarf pine (Pinus mugo), which is highly competitive and could be important in determining the composition of the invertebrate community. In this study, the association of species richness and abundance of butterflies with the extent of Pinus mugo cover at individual alpine sites was determined. Butterflies at alpine sites in the High Sudetes Mountains (Mts.) were sampled using Moericke yellow water traps. The results of a Canonical Correspondence Analysis (CCA) indicated that at a local scale the area of alpine habitats is the main limiting factor for native species of alpine butterflies. Butterfly assemblages are associated with distance to the tree-line with the optimum situated in the lower forest zone. In addition the CCA revealed that biotic factors (i.e. Pinus mugo and alpine tundra vegetation) accounted for a significant amount of the variability in species data. Regionally, the CCA identified that the species composition of butterflies and moths is associated with presence and origin of Pinus mugo. Our study provides evidence that the structure of the Lepidopteran fauna that formed during the postglacial period and also the present composition of species assemblages is associated with the presence of Pinus mugo. With global warming, Pinus mugo has the potential to spread further into alpine areas and negatively affect the local species communities.

• Klíčová slova
• Afforestation, Alpine tundra, Biodiversity loss, Central European mountains, Dwarf pine, Lepidoptera, Postglacial development,
• Publikační typ
• časopisecké články MeSH

Water brownification has long altered freshwater ecosystems across the northern hemisphere. The intensive surface water brownification of the last 30 years was however preceded by previous long-lasting more humic browning episodes in many catchments. To disentangle a cascade of browning-induced environmental stressors this longer temporal perspective is essential and can be reconstructed using paleolimnological investigations. Here we present a Holocene duration multi-proxy paleolimnological record from a small forest mountain lake in the Bohemian Forest (Czechia) and show that climate-related soil saturation and peatland development has driven surface water brownification for millennia there. A long core retrieved from the central part of the lake was dated using 14C and 210Pb, subsampled and analyzed for diatoms and zoological indicator (chironomids, planktonic cladocerans) remains. X-ray fluorescence (XRF) provided a record of elements sensitive to biogeochemical processes connected to browning and catchment development (P, Ti, Al/Rb, Fe/Ti, Mn/Ti, Si/Ti). Three threshold shifts related to the processes of water browning were detected in both diatom and chironomid successions at ~10.7, ~5.5 and ~4.2 cal. ky BP. Since, postglacial afforestation of the catchment ~10.7 cal. ky BP the lake experienced strong thermal stratification of the waters, but after ~6.8 cal. ky BP soil saturation and expansion of peatlands led to effective shading and probable nutrient limitation within the lake ecosystem. The more intensive in-wash of dissolved organic matter appears to decline after ~4.2 cal. ky BP, when the paludified catchment soils became permanently anoxic. Two temporary negative and positive anomalies of browning progress occur at the same time and may be connected with the "8.2 ka event" and the "4.2 ka event", respectively. The key role of peatlands presence in the catchment was manifested in millennial-scaled browning process and a climatic forcing of long-lasting browning is evidenced by coincidence with the moistening of climate across the northern hemisphere after ~6 cal. ky BP.

• Klíčová slova
• Bohemian Forest, Dystrophication, Humic substances, Mid-Holocene climate transition, Natural acidification, Paludification,
• MeSH
• ekosystém MeSH
• půda * MeSH
• voda * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• půda * MeSH
• voda * MeSH

The prevailing paradigm about the Quaternary ecological and evolutionary history of Central European ecosystems is that they were repeatedly impoverished by regional extinctions of most species during the glacial periods, followed by massive recolonizations from southern and eastern refugia during interglacial periods. Recent literature partially contradicts this view and provides evidence to re-evaluate this Postglacial Recolonization Hypothesis and develop an alternative one. We examined the long-term history of the flora of the Carpathian (Pannonian) Basin by synthesising recent advances in ecological, phylogeographical, palaeoecological and palaeoclimatological research, and analysing the cold tolerance of the native flora of a test area (Hungary, the central part of the Carpathian Basin). We found that (1) many species have likely occurred there continuously since before the Last Glacial Maximum (LGM); (2) most of the present-day native flora (1404 species, about 80%) can occur in climates as cold as or colder than the LGM (mean annual temperature ≤+3.5°C); and (3) grasslands and forests can be species-rich under an LGM-like cold climate. These arguments support an alternative hypothesis, which we call the Flora Continuity Hypothesis. It states that long-term continuity of much of the flora in the Carpathian Basin is more plausible than regional extinctions during the LGM followed by massive postglacial recolonizations. The long-term continuity of the region's flora may have fundamental implications not only for understanding local biogeography and ecology (e.g. the temporal scale of processes), but also for conservation strategies focusing on protecting ancient species-rich ecosystems and local gene pools.

• Klíčová slova
• Carpathian Basin, Last Glacial Maximum, Pleistocene, biodiversity conservation, paleoecology, phylogeography, recolonization, refugia, vegetation history,
• MeSH
• ekosystém * MeSH
• fylogeneze MeSH
• fylogeografie MeSH
• genetická variace * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH