The decline in groundwater levels is a cause of concern in many regions of the world, including the Sand Ridge of Hungary. The causes of the regional depletion range from rising air temperatures, changes in precipitation, domestic and agricultural groundwater use and past amelioration and recent afforestation, including the effects of drilling for crude oil exploration. The relations between the decline, the soil water regime and groundwater recharge under existing aged forests remained unclear thus far. Based on our monitoring of groundwater and soil moisture we aim to clarify this interplay in a new experimental site on the hilltop of the Sand Ridge. We compared three land-uses: a 41-year-old black locust (Robinia Pseudoacacia) offshoot forest, an 83-year-old first generation black pine (Pinus nigra) forest, and a grassland control site. The observed differences in the soil moisture profiles and dynamics were connected to the use of water by the given type of vegetation. We indicated a connection between the disruption of the groundwater recharge and the loss of contact of the rooting system of the forests with the deepening of the unconfined aquifer. Even if the aged forests could locally contribute to the decline, we conclude that the decline at the hilltop site that may be more strongly driven by other regional factors.
The aim of the study was to evaluate the climate and geographic factors controlling the hydrological drought of the rivers located in the Upper Vistula catchment in the Polish Carpathians. Drought was identified based on the daily flow (based on water stage measered once a day at 6 UTC) series dating from between 1975 and 2019 at 49 gauging cross-sections. Four physico-geographical regions were identified in the Polish Carpathians and spatial variabilities of the basic drought characteristics were developed within these regions. Such spatial distributions were treated as maps indicating drought hazard areas in the region. In addition, an analysis was undertaken to study the seasonality of the start and end times of the drought (all in the multi-annual period), the longest duration of droughts, the droughts of the highest volume in multi-annual period, as well as the number of drought days. Multi-annual variability of the number of drought days was also analysed. The results suggest that droughts in the Polish Carpathians are events characteristic of summer and autumn, whereas in the Tatra Mountains and the Podhale region - of autumn and winter. The greatest hazard of a prolonged and highvolume drought occurs in the Podhale region and the Tatra Mountains, while the lowest hazard is observed in the Bieszczady Mountains and the eastern part of the studied area.
The application of Brilliant Blue FCF tracer enables to identify flow types in multi-domain porous systems of soils via analyses of morphologic parameters of stained objects occurring in dye pattern profiles, as they represent the footprint of flow processes which occurred in soil during both the infiltration and the redistribution of dye solution. We analysed the vertical dye pattern profiles exposed for different time lengths, and revealed temporal evolution of dye solution redistribution leading to changes in flow types. The field experiment was performed with the Brilliant Blue tracer (the 10 g l–1 concentration) applied on 1m x 1m surface of the Dystric Cambisol. The top litter horizon had been removed before 100 l of the tracer was applied. Four vertical profiles were excavated on the experimental plot (always 20 cm apart) at different times after the irrigation had been finished: 2 hours (CUT 2), 24 hours (CUT 24), 27 hours (CUT 27) and 504 hours (CUT 504). The analyses of the dyed patterns profiles showed the spatio-temporal changes in the dye coverage, surface area density, average BB concentration, and stained path width, which allowed us to specify three stages of dye solution redistribution history: (i) a stage of preferential macropore flow, (ii) a stage of strong interaction between macropore-domain and soil matrix leading to the generation of heterogeneous matrix flow and fingering flow types, and (iii) a final stage of dye redistribution within the soil body connected with leaching of BB caused by meteoric water. With increasing time, the macropore flow types convert to mostly matrix-dominated FTs in the upper part of the soil profile. These results were supported by soil hydrological modelling, which implied that more than 70% of the soil moisture profiles variability among CUT 2–CUT 504 could be explained by the time factor.
Theoretical assumptions and practical approaches to temporal and spatial distribution of rainfall intensity in urban watersheds is still a research topic. The speed and direction of movement of rainfall events above urban watersheds are principal hydrologic parameters, which influence a rainfall-runoff process. This contribution reviews three methods, namely the Inverse Distance-Weighted Method (IDWM), Time Shift Method (TSM) and newly developed Geometrical Method (GM). The principal assumption of all three methods is based on the calculation of fictitious rainfall intensity at a particular location as weighted interpolation among the nearest real rain gauge stations. Any rainfall event above the urban watershed can be classified either as moving or non-moving storm. While the Inverse Distance-Weighted Method can be used for non-moving storms, the other two methods can describe the parameters of moving storms. Model RainGen, which was originally developed to create a basic source of rainfall data for rainfallrunoff mathematical models in urban watersheds, may be used not only for visualization but as well as for comparing of the measured and computed results. Case study for moving storms in Prague shows the results of TSM and GM methods. and Teoretické předpoklady a praktické přístupy k řešení časového a plošného rozložení srážek v urbanizovaných povodích jsou stále předmětem výzkumu. Rychlost a směr pohybu dešťových událostí nad urbanizovanými povodími představují hlavní hydrologické veličiny, které ovlivňují srážko-odtokový proces. Příspěvek se zabývá třemi metodami výpočtu, a to inverzní váhovou metodou, metodou časového posunu a nově navrženou geometrickou metodou. Hlavní předpoklad u všech tří metod je ve zvoleném místě založen na výpočtu fiktivní intenzity deště a to na základě interpolace s využitím váhové funkce mezi nejbližšími srážkoměrnými stanicemi. Každou srážkovou událost nad urbanizovaným povodím lze klasifikovat buď jako pohyblivou, nebo nepohyblivou. Zatímco inverzní váhová metoda může být použita pro nepohyblivé srážkové události, metodu časového posunu a geometrickou metodu lze doporučit pro pohyblivé srážkové události. Model RainGen, který byl původně vytvořen k tvorbě základních srážkových dat pro potřeby matematických modelů povrchového odtoku z urbanizovaných povodí, může být využit nejen k vizualizaci výsledků, ale rovněž k jejich vzájemnému porovnávání. Případová studie pohyblivých srážkových událostí v Praze ukazuje porovnání výsledků metody časového posunu a geometrické metody.
According to possibilism, or non-actualism, fictional characters are possible individuals. Possibilist accounts of fiction do not only assign the intuitively correct truth-conditions to sentences in a fiction, but has the potential to provide powerful explanatory models for a wide range of phenomena associated with fiction (though these two aspects of possibilism are, I argue, crucially distinct). Apart from the classic defense by David Lewis the idea of modeling fiction in terms of possible worlds have been widely criticized. In this article, I provide a defense of a possibilist account against some lines of criticism. To do so, I assume that names for fictional characters are directly referential and a possible-worlds model that accommodates transworld identity. On this background, I argue, it is possible to construct an elegant model of fictional discourse using familiar models of information exchange in ordinary discourse, and I sketch how this model can be used to i) make a natural distinction between fictional and counterfactual discourse, ii) account for creativity, and iii) sustain a natural definition of truth-in-fiction that avoids certain familiar objections to possibilism. Though I set aside questions about the metaphysical commitments of a possible-world interpretation here, there is accordingly reason to think that the battle over possibilist treatments of fiction will have to be fought over metaphysical foundations rather than technical shortcomings., Podle možnosti, nebo non-realismus, smyšlené znaky jsou možné jednotlivci. Potenciální účty beletrie nejenže přiřazují intuitivně správné pravdivostní podmínky věcem ve fikci, ale mají potenciál poskytovat silné vysvětlující modely pro širokou škálu jevů spojených s fikcí (ačkoli tyto dva aspekty possibilismu jsou, jak tvrdí, zásadně odlišné). Kromě klasické obrany Davida Lewise byla myšlenka modelování beletrie z hlediska možných světů široce kritizována. V tomto článku poskytuji obhajobu možného účtu proti některým kritikám. Abych tak učinil, předpokládám, že jména pro smyšlené postavy jsou přímo referenční a možný světový model, který přizpůsobuje transworld identitu. Na tomto pozadí argumentuji, je možné vytvořit elegantní model fiktivního diskursu za použití známých modelů výměny informací v běžném diskursu a načrtám, jak lze tento model využít k tomu, aby i) rozlišoval mezi fiktivním a protikladným diskurzem, ii) odpovídal za kreativitu a iii) udržovat přirozenou definici fikce pravdy, která se vyhýbá některým známým námitkám proti možnosti., Ačkoli jsem odložil otázky týkající se metafyzických závazků interpretace možného světa, je proto důvod domnívat se, že bitva o možnostech léčby beletrie se bude muset bojovat spíše na metafyzických základech než na technických nedostatcích. a načrtám, jak lze tento model využít k tomu, aby i) rozlišoval mezi fiktivním a kontrafaktuálním diskurzem, ii) odpovídal za kreativitu a iii) udržoval přirozenou definici pravdy-fiction, která se vyhýbá některým známým námitkám proti možnosti. Ačkoli jsem odložil otázky týkající se metafyzických závazků interpretace možného světa, je proto důvod domnívat se, že bitva o možnostech léčby beletrie se bude muset bojovat spíše na metafyzických základech než na technických nedostatcích. a načrtám, jak lze tento model využít k tomu, aby i) rozlišoval mezi fiktivním a kontrafaktuálním diskurzem, ii) odpovídal za kreativitu a iii) udržoval přirozenou definici pravdy-fiction, která se vyhýbá některým známým námitkám proti možnosti. Ačkoli jsem odložil otázky týkající se metafyzických závazků interpretace možného světa, je proto důvod domnívat se, že bitva o možnostech léčby beletrie se bude muset bojovat spíše na metafyzických základech než na technických nedostatcích., and Fredrik Haraldsen
Iodine is conventionally used as a contrast agent in hydrological laboratory experiments using polychromatic X-ray computed tomography (CT) to monitor two-phase Darcy flow in porous geological media. Undesirable beam hardening artifacts, however, render the quantitative analysis of the obtained CT images difficult. CT imaging of porous sand/bead packs saturated with iodine and tungsten-bearing aqueous solutions, respectively, was performed using a medical CT scanner. We found that sodium polytungstate (Na6H2W12O40) significantly reduced the beam hardening compared with potassium iodide (KI). This result is attributable to the location of the K absorption edge of tungsten, which is nearer to the peak of the polychromatic X-ray source spectrum than that of iodine. As sodium polytungstate is chemically stable and less toxic than other heavy element bearing compounds, we recommend it as a promising contrast agent for hydrological CT experiments.
The main purpose of the research was to determine the conditions affecting ice phenomena, including the three-phase cycle of ice: expansion, retention and decay of the ice cover on selected rivers of the Baltic coastal zone in the Northern Poland (Przymorze region). The analysis has been elaborated for the years 1951–2010 against the backdrop of currently occurring climatic changes, with particular emphasis on the development and phase variability of the NAO. The article presents the impact of the variability in atmospheric circulation which has manifested in an increase in air temperature, over the last 20 years, on thermal conditions during winter periods in the South Baltic Coastal Strip. The increase in air temperature has contributed to an increase in the temperature of river waters, thus leading to a shortening of the duration of ice phenomena on rivers in the Przymorze region. The article also brings to light an increased occurrence of winter seasons classified as cool, and a disruption in the occurrence of periods classified as normal over the last 30 observed years. The research has demonstrated a significant dependence between the seasonal change in air temperature and the variability of thermal conditions of water, which has a direct impact on the variability of the icing cycle of rivers in the Przymorze region. The authors also show that the variability in forms of ice phenomena for individual river sections is determined by the local factors, i.e. anthropogenic activity, impact of urbanized areas or inflow of pollutants.
The water retention capacity of coarse rock fragments is usually considered negligible. But the presence of rock fragments in a soil can play an important role in both water holding capacity and in hydraulic conductivity as well. This paper presents results of maximum water holding capacity measured in coarse rock fragments in the soil classified as cobbly sandy loam sampled at High Tatra mountains. It is shown, that those coarse rock (granite) fragments have the maximum retention capacity up to 0.16 volumetric water content. Retention curves of the four particular granite fragments have shown water capacity available for plants expressed in units of volumetric water content of 0.005 to 0.072 in the soil water potential range (0, -0.3 MPa). Available water capacity of stone fragments can contribute to the available water capacity of soil fine earth considerably and help to plants to survive during dry spells. and Hodnoty vodnej retenčnej kapacity hrubozrnných častíc skeletu v pôdach sa zvyčajne považujú za zanedbateľné. Avšak prítomnosť častíc skeletu v pôdach môže významne ovplyvňovať hodnoty vodnej kapacity pôdy ako aj jej hydraulickej vodivosti. Tento príspevok prezentuje výsledky merania maximálnej vodnej kapacity skeletu obsiahnutého v pôde. Pôdne vzorky boli odoberané v lokalite FIRE, Vysoké Tatry. Podľa meraní, hodnoty maximálnej retenčnej kapacity skeletu dosahovali 0,16 objemovej vlhkosti. Na základe retenčných kriviek pre 4 vybrané žulové kamene môžeme povedať, že hodnoty využiteľnej vodnej kapacity, vyjadrené v jednotkách objemu vody v pôde sa pohybovali od 0,005 do 0,072 pre vodný potenciál pôdy od 0 do -0,3 MPa. Využiteľná vodná kapacita častíc skeletu takto môže významne doplňovať využiteľnú vodnú kapacitu jemnozeme a pomáha rastlinám prežiť suché obdobia.
The ways how water from rain or melting snow flows over and beneath the Earth‘s surface affects the timing and intensity at which the same water leaves a catchment. Several mathematical techniques have been proposed to quantify the transit times of water by e.g. convolving the input-output tracer signals, or constructing frequency response functions. The primary assumption of these techniques is that the transit time is regarded time-invariant, i.e. it does not vary with temporarily changing e.g. soil saturation, evaporation, storage volume, climate or land use. This raises questions about how the variability of water transit time can be detected, visualized and analyzed. In this paper we present a case study to show that the transit time is a temporarily dynamic variable. Using a real-world example from the Lower Hafren catchment, Wales, UK, and applying the Continuous Wavelet Transform we show that the transit time distributions are time-variant and change with streamflow. We define the Instantaneous Transit Time Distributions as a basis for the Master Transit Time Distribution. We show that during periods of elevated runoff the transit times are exponentially distributed. A bell-shaped distribution of travel times was observed during times of lower runoff. This finding is consistent with previous investigations based on mechanistic and conceptual modeling in the study area according to which the diversity of water flow-paths during wet periods is attributable to contributing areas that shrink and expand depending on the duration of rainfall. The presented approach makes no assumptions about the shape of the transit time distribution. The mean travel time estimated from the Master Transit Time Distribution was ~54.3 weeks.
In this paper, I suggest a way of resolving the whole-part dilemma suggested in the Parmenides. Specifically, I argue that grabbing the second horn of the dilemma does not pose a significant challenge. To argue for this, I consider two theses about Forms, namely, the oneness and indivisibility theses. More specifically, I argue that the second horn does not violate the oneness thesis if we treat composition as identity and that the indivisibility thesis ought to be reinterpreted given Plato’s later dialogues. By doing so, I suggest a compositional understanding of Plato’s theory of Forms, which can resolve the whole-part dilemma.