This paper examines the changes in the species composition of aphids living in dry calcareous grasslands in Central Europe over a 25-year period. To the best of our knowledge, this is the first analysis of this type in the world that takes into account both previous and current data on species richness as well as groups of aphids that are distinguishable on the basis of biological and ecological criteria such as host-alternation and feeding types, life cycle, ecological niche, symbiosis with ants and their ecological functional groups. Over the period of more than 25 years, there has been a significant decrease in aphid α-diversity, from 171 to 105 species. The gain, which is in species not previously recorded, was 17 taxa. The loss of biodiversity occurred despite the fact that these habitats are protected and are valuable regional biodiversity hotspots. The losses are mostly related to intensive human activity in adjacent areas, which, unfortunately, has resulted in the isolation of these small, protected environmental islands by the removal of ecological corridors. Since, as is shown in this study, the frequencies between individual biological and ecological groups of aphids have been retained, it would be possible to restrict this loss of biodiversity if appropriate actions are taken., Barbara Osiadacz, Roman Hałaj, Damian Chmura., and Obsahuje bibliografii
Winter season temperatures are becoming warmer. However, the transformation of the ice regime on the Vistula River in Toruń has also been affected by river engineering. In particular, the construction and operation of the Włocławek Dam had a significant impact on ice processes. The article presents the results of an analysis determining the contribution of natural and anthropogenic factors to the duration of ice phenomena and ice cover on the Vistula River in the city of Toruń. Compared to the end of the nineteenth century, there has been a reduction in the duration of ice phenomena from 88 to 53 days and of ice cover from 40 to 7 days (in the period of 1882-2011). The article compares the duration of ice cover and winter temperature in three different periods: before the completion of river engineering works (1882-1907); for the controlled river (1908-1969), and for the controlled river with the Włocławek Dam upstream of Toruń (1970-2011). The results showed a significant role of these anthropogenic factors in the changes of the ice cover duration on the Vistula River in Toruń.
Land use has direct and indirect effects on the environmental conditions, which play a major role in the dynamics and changes in landscape. In Central Europe, the hemeroby approach is broadly used to quantify human impact on habitats and their vegetation. In this paper, the hemeroby approach was adopted for studying the rural settlements in the East Asian Republic of Korea. Flora and habitats of eight villages were analysed. The habitats were classified according to the five degrees on the hemeroby scale (oligo-, β-meso-, α-meso-, eu-, and polyhemerobic). Hemeroby indicator values were derived for species that were typical of a specific level of hemeroby. Habitats with the same level of hemeroby were grouped. The highest species number was found in habitats that were only moderately influenced by man. This corresponds to the intermediate disturbance hypothesis. The flora of habitats that were subject to the highest level of human impact (polyhemerobic)was characterized by a high proportion of annual species, but unexpectedly not by the highest proportion of non-native species.
Článek prezentuje výsledky pylové analýzy východočeské nížinné lokality Na bahně u Hradce Králové ve srovnání s analýzou rozsáhlého souboru archeologických záznamů z velké oblasti východních Čech. Radiokarbonové datování umožnilo synchronizaci výsledků pylové analýzy s vývojem osídlení od mladší doby železné (doby laténské) do současnosti. Křivky rozsahu osídlení a průměrného zastoupení antropogenních indikátorů vzájemně korespondují. Poprvé se tak pro území České republiky podařilo prokázat úbytek lidského tlaku na krajinu v době stěhování národů. V průběhu raného a především počátkem vrcholného středověku naopak dochází k výrazné synatropizaci krajiny a během novověku k postupné její proměně až po současný stav. and This article presents the results of pollen analyses at the East Bohemian lowland site of Na bahně near Hradec Králové, in comparison with analyses of the extensive archaeological assemblages from a wide area in eastern Bohemia. Radiocarbon dating has made it possible to synchronise the results of pollen analyses with settlement evolution from the later Iron Age (La Tène period) to the present. The curves of settlement extent and the average representation of anthropogenic indicators mutually correspond. For the first time in the Czech Republic, it has thus been possible to demonstrate the decrease in human impact on the landscape during the Migration Period. During the Early and (in particular) the High Middle Ages, on the hand, the pronounced synatrophisation of the landscape is clear, while during the Modern period there is a gradual transformation to the present situation.
Early investigations on the ecology of cities were in the tradition of natural history and focused on single biotopes. Of special interest were the plants and animals introduced into newareas directly or indirectly by man. In Central Europe, studies of anthropogenic plant migrations and cultural history were combined in a specific way, the so called Thellungian paradigm. The succession of vegetation on ruins after the bombing during the Second World War was studied in many cities. Ecological studies on whole cities started in the 1970s with investigations on energy flow and nutrient cycling. Today the term urban ecology is used in two different ways: in developing programs for sustainable cities, and in investigation of living organisms in relation to their environment in towns and cities.
Spatial variations in regional forest composition are analyzed for the period around 2 000 years before present in the territory of the Czech Republic. The results of pollen analyses at 16 different sites (original data and those published by other authors) form the basis of this study. The results are preliminary because of the small number of sites sampled. This article demonstrates the possibilities of the approach and is the first step to a wider application in the future. The conclusions indicate that pollen analysis is accurate enough in most cases for the reconstruction of past forest composition on a regional scale, and different deposits reflect spatial heterogeneity. Altitude, intensity of human impact, and soil type were the major factors affecting past distribution of forest trees. Oak and hornbeam woodlands, although widely affected by human activity, dominated the lowlands. Beech and silver fir were an important admixture in these communities. Although oak was present at higher altitudes, the occurrence of upland oak woodlands was limited more than indicated by recent geobotanical reconstructions. Instead, mixed forests existed at middle altitudes, often dominated by silver fir and beech. In less favourable habitats, spruce was common. Such upland forests extended high into the mountains, where because of the more severe climatic conditions beech and spruce started to dominate over silver fir.
Pollen and macroscopic analyses of two Upper Holocene spring fen sites in the vicinity of the Turček village in the south-western foothills of the Kremnické vrchy Mts (central Slovakia) revealed new and unique information on the precultural and natural climazonal forests, and the origin and development of local meadow fen vegetation. Pollen-analytical data indicate the prevalence of natural spruce (Picea abies) and fir (Abies alba) forests in this region. The mixed beech forests depicted on the geobotanical map of Slovakia must have, therefore occupied much smaller areas than previously thought. After human colonization of the region during the 13th and 14th centuries natural forests were transformed mainly into grasslands and pastures, and to a lesser extent into arable fields. These changes were connected with gold and silver mining in the vicinity of the nearby town of Kremnica, with Turček one of the important areas producing timber for the mining industry. The development of these fen mires is also connected with deforestation and transformation of the landscape. They originated as forest springs but after human colonization of the area they were transformed into treeless fen meadows by the direct or indirect effect of man cutting of trees, grazing livestock and mowing.
In the subcontinental, semiarid lowland region of Central Bohemia (Czech Republic), continuous human impact acting together with diverse natural environmental conditions resulted in the present extraordinarily complex pattern of vegetation. Three radiocarbon-dated pollen diagrams for the area indicate that this complexity results from past vegetation development. During prehistory, places suitable for settlement (with respect to climate, geology, hydrology, etc.) were colonized and transformed first. This resulted in a diachrony in vegetation development due to human activity starting in the first half of the Holocene. This caused an increase in diversity in the region as plant species persisting from previous periods, along with those associated with different agricultural practices, increased. Local abiotic factors affected not only the chronology of human impact but also its specific effects on the ecosystem. Anthropogenic pressure may have had different effects under different conditions. Human population pressure was the mediator between the abiotic diversity and selectively transformed vegetation suitable for the respective habitats. Differences in the chronology of human impact, mixed oak woodland degradation, and the chronology of beech, silver fir and hornbeam expansion are documented for the different ecological zones of the study area. These differences shed light on the mechanisms resulting in some of the important changes in Holocene vegetation. In the absence of man, the decline in mixed oak woodlands, typical of the Middle Holocene in Central Bohemia, would have been probably much slower and less extensive. Unlike in the uplands and mountains, the expansion in the area of beech, silver fir and hornbeam would have been insignificant. The present vegetation resulted to a large extent from management during High Middle Ages. There is almost no continuity in vegetation from the late prehistory to the present.