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1282. Soudobé dějiny
- Type:
- model:periodicalitem and TEXT
- Language:
- Czech, English, and Slovak
- Description:
- 2
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1283. Soudobé dějiny
- Type:
- model:periodicalitem and TEXT
- Language:
- Czech, English, and Slovak
- Description:
- 4
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1284. Soudobé dějiny
- Type:
- model:periodicalitem and TEXT
- Language:
- Czech, English, and Slovak
- Description:
- 4
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1285. Soudobé dějiny
- Type:
- model:periodicalitem and TEXT
- Language:
- Czech, English, and Slovak
- Description:
- 3-4
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1286. Spatial and temporal variability of snow isotopic composition on Mt. Zugspitze, Bavarian Alps, Germany
- Creator:
- Hürkamp, Kerstin, Zentner, Nadine, Reckerth, Anne, Weishaupt, Stefan, Wetzel, Karl-Friedrich, Tschiersch, Jochen, and Stumpp, Christine
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- stable isotopes of oxygen and hydrogen in water, snow profile, snowmelt runoff, and isotope fractionation
- Language:
- Slovak
- Description:
- High amounts of precipitation are temporarily stored in high-alpine snow covers and play an important role for the hydrological balance. Stable isotopes of hydrogen (δ2H) and oxygen (δ18O) in water samples have been proven to be useful for tracing transport processes in snow and meltwater since their isotopic ratio alters due to fractionation. In 18 snow profiles of two snowfall seasons, the temporal and spatial variation of isotopic composition was analysed on Mt. Zugspitze. The δ18O and δ2H ranged between –26.7‰ to –9.3‰ and –193.4‰ to –62.5‰ in 2014/2015 and between –26.5‰ to –10.5‰ and –205.0‰ to –68.0‰ in 2015/2016, respectively. Depth-integrated samples of entire 10 cm layers and point measurements in the same layers showed comparable isotopic compositions. Isotopic composition of the snowpack at the same sampling time in spatially distributed snow profiles was isotopically more similar than that analysed at the same place at different times. Melting and refreezing were clearly identified as processes causing isotope fractionation in surficial, initial base or refrozen snow layers. For the future, a higher sampling frequency with detailed isotopic composition measurements during melt periods are recommended to improve the understanding of mass transport associated with snowmelt.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1287. Spatial variability of snow water equivalent - the case study from the research site in Khibiny Mountains, Russia
- Creator:
- Komarov, Anton Yu., Seliverstov, Yury G., Grebennikov, Pavel B., and Sokratov, Sergey A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- snow water equivalent, snow height, snow density, and accuracy of measurements
- Language:
- Slovak
- Description:
- The aim of the investigation was assessment of spatial variability of the characteristics of snowpack, including the snow water equivalent (SWE) as the main hydrological characteristic of a seasonal snow cover. The study was performed in Khibiny Mountains (Russia), where snow density and snow cover stratigraphy were documented with the help of the SnowMicropen measurements, allowing to determine the exact position of the snow layers’ boundaries with accuracy of 0.1 cm. The study site was located at the geomorphologically and topographically uniform area with uniform vegetation cover. The measurement was conducted at maximum seasonal SWE on 27 March 2016. Twenty vertical profiles were measured along the 10 m long transect. Vertical resolution depended on the thickness of individual layers and was not less than 10 cm. The spatial variation of the measured snowpack characteristics was substantial even within such a homogeneous landscape. Bulk snow density variability was similar to the variability in snow height. The total variation of the snowpack SWE values along the transect was about 20%, which is more than the variability in snow height or snow density, and should be taken into account in analysis of the results of normally performed in operational hydrology snow course SWE estimations by snow tubes.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1288. Spatio-temporal analysis of remotely sensed and hydrological model soil moisture in the small Jičinka River catchment in Czech Republic
- Creator:
- Đukić, Vesna, Erić, Ranka, Dumbrovsky, Miroslav, and Sobotkova, Veronika
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- SHETRAN hydrological model, downscaled remotely sensed soil moisture, runoff and soil moisture validation, spatio-temporal variability of soil moisture, flash floods, and small catchment
- Language:
- Slovak
- Description:
- The knowledge of spatio-temporal dynamics of soil moisture within the catchment is very important for rainfall– runoff modelling in flood forecasting. In this study the comparison between remotely sensed soil moisture and soil moisture estimated from the SHETRAN hydrological model was performed for small and flashy Jičinka River catchment (75.9 km2) in the Czech Republic. Due to a relatively coarse spatial resolution of satellite data, the satellite soil moisture data were downscaled, by applying the method developed by Qu et al. (2015). The sub-grid variability of soil moisture was estimated on the basis of the mean soil moisture for the grid cell and the known hydraulic soil properties. The SHETRAN model was calibrated and verified to the observed streamflow hydrographs at the catchment outlet. The good correlation between the two different soil moisture information was obtained according to the majority of applied criteria. The results of the evaluation criteria indicate that the downscaled remotely sensed soil moisture data can be used as additional criteria for the calibration and validation of hydrological models for small catchments and can contribute to a better estimation of parameters, to reduce uncertainties of hydrological models and improve runoff simulations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1289. Spatio-temporal variation of throughfall in a hyrcanian plain forest stand in Northern Iran
- Creator:
- Yousefi, Saleh, Sadeghi, Seyed Hamidreza, Mirzaee, Somayeh, van der Ploeg, Martine, Keesstra, Saskia, and Cerdà, Artemi
- Type:
- article, model:article, and TEXT
- Subject:
- Caspian Hyrcanian Forest, deciduous forest, Forest hydrology, interception storage, and precipitation loss.
- Language:
- Slovak
- Description:
- Elucidating segregation of precipitation in different components in forest stands is important for proper forest ecosystems management. However, there is a lack of information on important rainfall components viz. throughfall, interception and stemflow in forest watersheds particularly in developing countries. We therefore investigated the spatiotemporal variation of important component of throughfall for a forest stand in a Hyrcanian plain forest in Noor City, northern Iran. The study area contained five species of Quercus castaneifolia, Carpinus betulus, Populus caspica and Parrotia persica. The research was conducted from July 2013 to July 2014 using a systematic sampling method. Ninetysix throughfall collectors were installed in a 3.5 m × 3.5 m grid cells. The canopy covers during the growing/leaf-on (i.e., from May to November) and non-growing/leaf-off (i.e., from December to March) seasons were approximately 41% and 81%, respectively. The mean cumulative throughfall during the study period was 623±31 mm. The average throughfall (TF) as % of rainfall (TFPR) during leaf-on and leaf-off periods were calculated 56±14% and 77±10%, respectively. TF was significantly (R2 = 0.97, p = 0.00006) correlated with gross precipitation. Percent of canopy cover was not correlated with TF except when gross precipitation was <30 mm. A comparison between leaf-off and leaf-on conditions indicated a significantly higher TFPR and corresponding hotspots during leaf-on period. TFPR also differed between seasons with a maximum amount in winter (82%). The results of the study can be effectively used by forest watershed managers for better perception of hydrological behavior of the Hyrcanian forest in the north of Iran under different silvicultural circumstances leading to getting better ecosystem services.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1290. Species as individuals: just another class view of species
- Creator:
- Pušić, Bruno
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- essential properties, ontological status of species, species as individuals, species as classes, and specific mate recognition system
- Language:
- Slovak
- Description:
- In this paper I will present an argument that the view of species having the ontological status of individuals implies that species actually have the ontological status of classes, despite the fact that the representatives of the view that species are individuals (or SAI) claim the contrary. Representatives of the SAI view try to argue that species cannot be classes because classes cannot change. I will show that, according to the representatives of the SAI view, groups of organisms must fulfill four necessary conditions in order to be treated as species. They must be: 1. integrated and continuous spatiotemporal genealogical lineages of organisms that are their constituent elements; 2. separated from the continuous genealogical lineage, from the last known common ancestor to modern organisms, by evolutionary unity; 3. made up of organisms going through the same or similar evolutionary processes; 4. groups of organisms whose members reproduce sexually. I will also show that when these conditions are compared to the list of extrinsic essential properties made by Caplan and Devitt it will be apparent that they are the same. In conclusion I will argue that if, under the SAI view, one of the necessary conditions that groups of organisms must fulfill in order to be treated as species is that members of the species must reproduce sexually, then each member of the species must possess the same specific mate recognition system or SMRS, which in turn makes SMRS an intrinsic essential property of each member of the species. What follows from this is that, according to the species and individuals view, species are in fact classes. and V tomto příspěvku předkládám argument, že názor druhu, který má ontologický status jednotlivce, naznačuje, že druhy skutečně mají ontologický status tříd, navzdory skutečnosti, že zástupci názoru, že druhy jsou jednotlivci (nebo SAI) . Zástupci názoru SAI se snaží tvrdit, že druhy nemohou být třídy, protože se třídy nemohou měnit. Ukážeme, že podle zástupců názoru SAI musí skupiny organismů splňovat čtyři nezbytné podmínky, aby byly považovány za druhy. Musí to být: 1. integrované a nepřetržité vesmírné směrové genealogické počty organismů, které jsou jejich složkami; 2. odděleno od kontinuálního genealogického počinu, od posledního známého společného předka moderním organismům, evoluční jednotou; 3. složený z organismů procházejících stejnými nebo podobnými evolučními procesy; 4. skupiny organismů, jejichž členové reprodukují sexuálně. Budu také ukázat, že když jsou tyto podmínky porovnány se seznamem hlavních vnějších vlastností, které vytvořily Caplan a Devitt, bude zřejmé, že jsou stejné. Závěrem se domnívám, že pokud podle názoru SAI je jednou z nezbytných podmínek, které musí skupiny organismů splnit, aby se s nimi zacházelo jako s druhem, je to, že členové druhu musí reprodukovat sexuálně, pak každý člen druhu musí mít stejnýspecifický systém rozpoznávání matek nebo SMRS, což zase dělá SMRS podstatnou základní vlastností každého člena druhu. Z toho vyplývá, že podle pohledu druhů a jednotlivců jsou druhy ve skutečnosti třídy.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public