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Ito equations are derived for simple stochastic cellular automaton with parameters describing efficiencies for avalanche triggering
and cell occupation. Analytical results are compared with the numerical one obtained from the histogram method. Good agreement
for various parameters supports the wide applicability of the Ito equation as a macroscopic model of some cellular automata
and complex natural phenomena which manifest random energy release. Also, the paper is an example of effectiveness of histogram
procedure as an adequate method of nonlinear modeling of time series. 相似文献
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Local‐ and regional‐scale biomorphodynamics due to tree uprooting in semi‐natural and managed montane forests of the Sudetes Mountains,Central Europe 
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下载免费PDF全文 In this work, direct and indirect geomorphic consequences of wind‐related tree uprooting are examined, using an extensive dataset from the mountain range of the Sudetes, Poland. The role of local conditions in influencing the geomorphic efficacy of tree uprooting is examined, as well as issues of upscaling individual observations from experimental sites. This problem is approached at a range of spatial and observational scales, from monitoring of root plate degradation over time through to examination of wind effects at a slope scale and region‐wide analysis. In our study area the mean root plate volume is between 0.4 and 4.2 m3 for spruce and 2.4 m3 for beech, and their degradation may last tens of years. The density of relict pit‐and‐mound microtopography varies from 2.7 up to 40 pairs per hectare and the maximum coverage of terrain is 4.7%. The volume of treethrow mounds varies from 0.5 to 3.1 m3 and mounds seem to outlive the pits formed in the same episode of disturbance. However, in specific lithological and topographic conditions, pit‐and‐mound topography does not form. The maximum biogenic transport attributable to a single windstorm event is c. 80 m3 ha?1, while soil turnover times are calculated in the order of 1000–10 000 years. Rock fragment ‘mining’ is an important biogeomorphic process, both in terms of impact on hillslope surfaces and on soil properties. Gravel armours and small‐scale stepped topography may form instead of typical pit–mound associations in specific circumstances. Managed forests appear more prone to wind damage and associated geomorphic consequences. In the Sudetes Mountains, the variable role of tree uprooting in local and regional hillslope denudation is governed by forest stand structure, topography and regolith properties, with the former significantly influenced by human activity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Sergey Dolomatov Walery Zukow Maciej Dzierzanowski Jan Mieszkowski Radoslaw Muszkieta Mariusz Klimczyk 《Water Resources》2016,43(1):177-183
The paper reviews scientific and practical aspects of research on the metabolism of nitrates into nitrate (nitrite) reductase in the nitric oxide cycle in fish under hypoxic conditions. Literature data are given about enzymes involved in nitrate reductase reactions and how oxygen shortage affects their activity. The environmental factors that may participate in the processes of nitrate reduction to nitrites as well as the ones which may influence the kinetics of nitrate in fishes are considered. Examined results indicate that certain components of the conservative L-arginine-dependent nitric oxide cycle pass in a number of vertebrate animals. Then, the contour cycle of nitric oxide in the fish shows a wide range of diversity which is represented by phylogenetically ancient biochemical mechanisms of nitrite (nitrate) reductase. First of all, the presence or absence of hemoglobin is distinguished. Secondly, a wider range of expression of different myoglobin isoforms appears. Furthermore, the kinetics of nitrates in fish is distinctly dependent on abiotic environmental factors. The analysis of the literature confirms the thesis that nitrates are an important substrate for the nitrate (nitrite) reductase loop cycle of nitric oxide in fishes. Secondly, their role in the compensation of arginineindependent NO synthesis increases with decreasing oxygen levels in the environment. Thirdly, the provided research results are a basis for indicating xanthine oxidase and possibly the microflora of the digestive system as the basic units of the nitrate reductase system in the body of fish. The practical aspect of the question, in our opinion, is the most meaningful presence of numerous studies that emphasize the need to find physiological reactions that precede the formation of pathological changes induced by the influence of combined effects of nitrates and hypoxia on the organism of fish. 相似文献
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Anna?KlosEmail author Janusz?Bogusz Mariusz?Figurski Maciej?Gruszczynski 《Studia Geophysica et Geodaetica》2016,60(1):17-34
Each of the GPS time series that describes the changes of topocentric components consists of a deterministic and a stochastic part, whose character influences the errors of the deterministic parameters. As to the uncertainties of reliable velocities of permanent satellite station systems, surveys that estimate and take into account any dependencies that may affect subsequent operational efficiency are very important. For this analysis, we used 42 stations from the IGS (International GNSS Service) network from Europe, processed at the Military University of Technology EUREF Permanent Network Local Analysis Centre (MUT LAC). The deterministic part of the GPS time series was removed using the least squares method. The seasonal periods in topocentric components were determined assuming the existence of the residual Chandler oscillation (1.67 cpy), as well as the annual tropical (1 cpy) and draconitic (1.04 cpy) oscillations with their harmonics up to 4th. We assumed the character of the residue as a combination of white and powerlaw noise. The obtained results show, that in the case of the European sub-network of IGS stations we are dealing with the coloured noise between white and flicker noise with the amplitudes between 3 to 6 mm/year-k/4 for horizontal components and between 6 to 15 mm/year-κ/4 for the vertical ones, where κ is a spectral index. Finally, we showed that the amplitudes and spectral indices of noise are reduced after performing a spatio-temporal filtering. All the elicited results referred to the uncertainties of velocities by estimating them before and after filtration and the simulation of their values for different lengths of the time series. 相似文献
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Mariusz Lamentowicz 《Journal of Paleolimnology》2010,43(3):499-511
Our palaeoecological study covers 73 years of history (1929–2002) of a kettle hole peatland inundated by water from a nearby,
dammed lake. Testate amoebae, pollen and non-pollen palynomorphs (NPPs) were used to track the shift to wetter conditions
in the peatland. Lead-210 was used to try and construct the chronology. We investigated how peatland testate amoebae communities
changed since the damming of a nearby river. Furthermore, we evaluated how rapidly local vegetation responded to the increase
in wetness, and how vegetation changes correlated with shifts in testate amoebae and NPPs. The Mukrza kettle hole provided
palaeoecological evidence of trophic state and hydrological changes since the lake filled with water in 1929. Three stages
of development were revealed. The first two were associated with initial inundation, and the third was related to Sphagnum expansion and acidification. Quantitative reconstruction of groundwater level and pH, inferred using testate amoebae, confirmed
our hypotheses about changes in hydrology and trophic state. Subfossil desmid remains lend qualitative support to the reconstruction.
The ecology of several testate amoeba taxa is discussed in the context of succession and population establishment. There was
complete species replacement since the time of inundation. Our investigation has two important applied aspects: (1) it enables
prediction of the response of peatlands to a rise in water table on restored sites; and (2) it provides analogues for palaeoclimatological
studies. The history of the Mukrza mire is an example of how palaeoecological studies can be used to assess the degree of
change in peatlands transformed by human activities. 相似文献
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Nicola Masini Luigi Capozzoli Gerardo Romano Dominika Sieczkowska Maria Sileo Jose Bastante Fernando Astete Victoria Mariusz Ziolkowski Rosa Lasaponara 《Surveys in Geophysics》2018,39(6):1239-1262
Even if, in recent decades, the use of remote sensing technologies (from satellite, aerial and ground) for archaeology is stepping into its golden age, in Southern America geophysics for preventive archaeology is more recent and less used than in Europe, Central America and Middle East. In this paper, we provide a brief overview and show the preliminary results obtained from the investigations conducted in Chachabamba (Peru). The archaeological area is located on a strategic terrace overlooking three Inca roads, which served the most important ceremonial centres (including Machu Picchu) of the Urubamba Valley also known as the Sacred Valley. In particular, Chachabamba investigations were conducted with two principal aims: (1) to give new impetus to archaeological research with targeted investigations aimed at improving and completing the site’s knowledge framework; (2) to experiment and validate an archaeogeophysical approach to be reapplied in other sites of the Urubamba valley, including Machu Picchu, having similar characteristics as those found in Chachabamba. 相似文献
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Edyta Puskarczyk Paulina Krakowska Mariusz Jędrychowski Magdalena Habrat Paweł Madejski 《Acta Geophysica》2018,66(6):1453-1461
The main goal was the analysis of parameters describing the structure of the pore space of carbonate rocks, based on tomographic images. The results of CT images interpretation, made for 17 samples of Paleozoic carbonate rocks were shown. The qualitative and quantitative analysis of a pore system was performed. Objects were clustered according to the pore size. Within the clusters, the geometry parameters were analysed. The following dependences were obtained for carbonate rocks, also for individual clusters (due to the volume): (1) a linear relationship (on a bilogarithmic scale) between the specific surface and the Feret diameter and (2) a strong linear relationship between specific surface area and Feret diameter and average diameter of the objects calculated for the sphere. The results were then combined with available results from standard laboratory tests, including NMR and MICP. 相似文献
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Ptak Mariusz 《中国地理科学(英文版)》2017,27(1):8-12
Water deficits observed in many regions of the world make it necessary to implement measures intended to improve this situation. Poland is one of the countries with the poorest water resources in Europe due to its natural conditions and human impact. As a result of land reclamation carried out over decades, many elements of its hydrographic system have been changed, and some of them, like lakes, have disappeared altogether. In the days of the socio-economic transformation and more frequent extreme events, what seems worth considering is the renaturalisation of non-existing lakes, an idea presented in this paper on a selected example. 相似文献