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Will Xerothermic Grasslands of the Ponidzie Region Survive?

Abstract

Xerothermic grasslands are veritable botanical gems of the Ponidzie region, located in the upland zone of Poland. Most of these exceptional plant communities have been formed as a result of deforestation, in habitats characterized by specific climatic, hydrological and soil conditions. The result of the natural reserve protection of the xerothermic grassland, however, is opposite to the desired result. The survival of the xerothermic grassland depends on the change in the approach to their protection. Xerothermic grasslands are an excellent example of the difficulties with maintaining very valuable, but semi-natural and anthropogenic communities, related to a large extent to traditional, extensive forms of agriculture. Similar problems occur in the case of gladiolus meadows in lower subalpine forest zones or of once-mown molinion meadows in river valleys.

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Borders on the old maps of Jizera Mountain

Introduction The state border is a barrier that most people perceive and use to construct their identity vis-à-vis the neighbouring country ( van Houtum 1999 ). However, boundaries and their depiction on maps can bear multiple forms: most of the time, we provide other administrative–political boundaries where states are divided into smaller units, such as regions, provinces, counties or districts. Some of these borders have survived since their creation to the present, others serve as memory (see Jańczak’s concept of the phantom border, 2014). In our article

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Euryhaline preferences of the decapod crab Mioplax socialis enabled it to survive during the Badenian/Sarmatian extinction (Miocene) in the Central Paratethys

Abstract

Although decapod crustaceans of the Central Paratethys were diverse during the Badenian (Langhian-Early Serravallian), a dramatic drop in their diversity occurred at the boundary with the Sarmatian. A crab Mioplax socialis is one of the few decapods reported from the Lower Sarmatian (Mohrensternia Zone) of the Paratethys. Until now, this species has been known from only a handful of specimens from Austria, Croatia and Bulgaria (Central Paratethys), and its systematics and ecology remain poorly known. Here, on the basis of new specimens from the Sarmatian tuffitic clays of the Stretava Formation (Skároš, Eastern Slovakia) we confirm that this species belongs to the subfamily Chasmocarcininae. The diagnostic characters of the male sternum that allow this classification are reported for the first time. The molluscan assemblage co-occurring with M. socialis demonstrate that this species tolerated conditions with variable salinity. Its tolerance of a broad range of salinity regimes may thus explain its survival across the Badenian-Sarmatian extinction event. Preservation of near-complete and fully articulated individuals of M. socialis suggests calm conditions and short residence times on the sediment-water interface.

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Human-planted alder trees as a protection against debris flows (a dendrochronological study from the Moxi Basin, Southwestern China)

Abstract

Large debris flows have destroyed the infrastructure and caused the death of people living in the Moxi Basin (Sichuan Province, Southwestern China). Inhabitants of the Moxi Basin live on the flat surfaces of debris-flow fans, which are also attractive for farming. During the monsoon season debris flows are being formed above the fans. Debris flows can destroy the houses of any people living within the fan surfaces. In order to prevent the adverse effects of flows, people plant alder trees (Alnus nepalensis) at the mouths of debris flow gullies running above debris flow fans. Alders are able to capture the debris transported during flow events. Trees are well adapted to surviving in conditions of environmental stress connected with abrupt transport and deposition of sediment from debris flows. Numerous wounds, tilting and bending of alder trees caused by debris flows only very rarely cause the death of trees. By dating scars and dating the time of alder tilting (through the analysis of annual rings), we have determined the frequency of debris flows occurring at the mouth of the Daozhao valley. In 1980–2012 within the studied debris-flow fan and the Daozhao gully, 2 large debris flow events occurred (1996, 2005) and some smaller events were probably recorded every 2–3 years.

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The influence of wealth on philanthropy: A cross-regional study

Abstract

Even in situations when welfare state budgets can be considered generous, many socially responsible, beneficial activities remain that cannot survive without the financial support of private individual or corporate donors. The article seeks an answer to questions of to what extent the willingness to donate one’s own money depends on wealth and income, and what the role of other socio-cultural factors is. The data about the amount of private and corporate donations in particular regions of the Czech Republic in the period of the years 2011–2015 is compared with data about the regional economic prosperity and income. The regression analysis results show that it was only possible to explain to certain level the amount of donations by the rate of the wealth of firms and individuals in particular regions. In case of the companies, it is a medium-strong correlation, while the correlation is strong in terms of individuals. Particularly in terms of the corporate donation, the willingness to donate is significantly related also with other, non-economic factors in the region.

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The Valley-Fill Deposits of the Kłodnica River (Southern Poland): Environmental Drivers of Facies Changes from the Late Vistulian Through the Holocene

The Valley-Fill Deposits of the Kłodnica River (Southern Poland): Environmental Drivers of Facies Changes from the Late Vistulian Through the Holocene

Lithological analyses and radiocarbon dating were used to elucidate the patterns and controls of Late Quaternary valley floor development of the Kłodnica River, the Upper Odra Basin. The research results were discussed with data obtained from valleys of rivers draining piedmont basins and highlands of southern Poland. In consequence, five stages of morpho-sedimentary evolution of the Kłodnica valley were distinguished. In the Late Vistulian a large-scale deposition of channel alluvium took place in the conditions of high river discharges. This sedimentary style probably still existed in the Early Pre-Boreal as long as open grass communities survived in the Kłodnica catchment. The next phase, in the Late Pre-Boreal and Boreal, is characterized by a significant increase in accumulation rate of biochemical facies. The considerable restriction of minerogenic deposition was connected with widespread of forest and gradual limitation of the river discharges. The third stage began at the decline of the Boreal and was defined by decrease of accumulation rate or even biogenic accumulation break. Synchronously, periodic increases of fluvial activity were noticed in the form of cutoffs of meander loops and overbank deposition in oxbows. The beginning of the fourth period took place not earlier than in the Early Sub-Boreal. This stage was distinguished by renewed peat growth/increase in biochemical accumulation rate and periodic increase in alluviation, generally taking place in the conditions of low channel-forming flows. The latest phase (from the Middle Sub-Atlantic till now) is characterized by common initiation of slope deposition and a rapid increase in fluvial sedimentation, especially overbank and tributary fan facies. An increase in minerogenic deposition occurred in response to human impact, which became more significant from the Roman Period and occurred on a large scale from the early Middle Ages. Older settlement phases, including intense settlement from the Hallstatt Period, were not clearly recorded in the Kłodnica valley fill.

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Phenological Analysis of the Last Glacial Vertebrates from the Territory of Moravia (the Czech Republic) – Continuity and Change in Faunistic Communities

Abstract

Due to the vertical zonality of the studied area, its environment varied greatly over a relatively short distance within the same time span. It is possible to distinguish the following different types of environment: (1) Alluvial floodplains around larger water flows. I assume in the Last Glacial there was continuous coniferous forest, with occasional sporadic occurrences of thermophilous deciduous trees in favourable locations mainly in south Moravia. (2) Lower foothills up to about 300 m a.s.l. along the floodplains, probably the most widespread type of environment in the studied area. Open grasslands with isolated trees and shrubs were predominant. (3) At the higher altitudes of the hills (ca. 300-500 m a.s.l.) there was only steppe. (4) The highest parts of highlands and the mountains (500-1,400 m a.s.l.). During the cold and dry events these areas were mostly without grassy vegetation. The boundaries of the above mentioned environments fluctuated throughout the whole of the Last Glacial. A series of new investigations of Last Glacial Moravian sites took place over the recent decades. The result was a relatively large amount of fossil vertebrate findings, from karst areas (caves), and from open air sites. All findings were assigned to precisely defined layers which were in most cases radiometrically and/or archaeologically dated. It allowed association of the fauna communities with stratigraphical events and therefore produced a clearer picture of changes during the entire Last Glacial. The study showed that the species structure of the communities was not stable during the Last Glacial. The changes did not exhibit gradual linear development. The time span of the individual communities varied greatly. In two cases a total species change occurred very rapidly. In other cases the changes occurred over a longer period of time and may have involved penetration of new species into existing communities to a significant extent. The changes of communities associated with single stratigraphical events were palaeoecologically evaluated. In comparison with changes in the environment, I can conclude that both changes occurred simultaneously. I am therefore convinced that the primary impulse for community change was induced by environmental change. The Eemian communities of regions east of Germany differ from coeval communities of Western and the west part of Central Europe. This difference was driven by variation in precipitation, a more humid climate in the West and continental climate in the East. We have therefore two different Eemian provinces in Central Europe, the more humid west (oceanic weather) and the drier east (continental weather). The first half of the Last Glacial, about 40 ka from its beginning, had a wide range of climatic oscillations of different intensity. In layers of Moravian localities with interglacial species, the numbers of finds are always limited (small number). They were previously assigned to the Eemian. The earlier stratigraphic scale of the Late Pleistocene corresponded with this view. According to recent opinion, however, the rare finds of interglacial species in these localities are not from the Eemian interglacial, but from the first interstadials of the Last Glacial. Larger temperature oscillations occurred only in the second half of the Last Glacial and the most significant cooling was at the very end of this time. In the first occurrence of the typical Holocene assemblage in the Moravian Karst there are still some species which are typical for the Last Glacial (reindeer and lemmings). Lemmings died out first, but reindeer survived up to the Neolithic age. This area had, and still has today, differing environments within a relatively short distance caused by vertical zonation. There was a significantly colder climate in the deep and relatively narrow valleys. The upper part of the insolation slopes was mainly covered with grass and the average annual temperature there was much higher than in the valleys. This was reflected of course in the fauna. The in-migration of animals was not only via a meridional route. Migration was not only caused by oscillation of the average temperature or rainfall, but also by the need to find the best conditions for living. Seasonal migration was caused mainly by annual changes in the energy value of the food plants.

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Historical Influence of Man on the Vegetation Record in the Prášilské Lake Sediments (Bohemian Forest, Czech Republic)

, geomorphological and palaeoecological research of the sediments in the Srni area). Zpr. geol. Výzk. v Roce 2005, 62-64. Praha. Břízová E., Juřičková L. 2011. Could canopy forests survive agricultural colonization in the Polabi lowland (Czech Republic)? Bulletin of Geosciences 86, 2, 283-300. ISSN 1214-1119. DOI 10.3140/bull.geosci.1260. Břízová, E., Mentlík, P. 2005a. Za tajemstvim Stare jimky na Prašilsku. Šumava, 11, jaro 2005, 18-19. Vimperk. Břízová, E., Mentlík, P. 2005b. Preliminary results of geomorphological research and

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A review of the Pleistocene dwarfed elephants from the Aegean islands, and their paleogeographic context

: 2037–2044. https://doi.org/10.1016/j.csr.2008.11.005 Markov, G. N. (2007): Elephas antiquus (Mammalia: Proboscidea) in Bulgaria. – Historia naturalis bulgarica, 18: 161–166. Marra, A. C. (2009): Pleistocene mammal faunas of Calabria (Southern Italy): biochronology and palaeobiogeography. – Bollettino della Società Paleontologica Italiana, 48(2): 113–122. Masseti, M. (2001): Did endemic dwarf elephants survive on Mediterranean islands up to prehistorical times? – In: Cavarretta, G., Gioia, P., Mussi, M., Palombo, M. R. (eds), The World of

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Some novel features of post-500°C heating blue stimulated OSL emission of fired natural quartz

carried out to see the thermal stability of different OSL components of quartz showed the removal of both, the fast and medium component with preheating at higher temperatures, around 400°C ( Jain et al ., 2003 ; Singarayer and Bailey, 2003 ). The component of OSL observed to survive with such high pre-heating temperature was found to be only the slow component Singarayer and Bailey, 2003 ; Bailey, 2000 ). The nature of bleaching of fast and medium components was seen to be similar with different stimulation photon energies ( Singarayer and Bailey, 2003 ). The ratio

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