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Precipitation and Air Temperature Impact on Seasonal Variations of Groundwater Levels

. Latvijas valsts izdevniecība, Rīga, 1960. 203 lpp. 16. Levina, N., Levins, I. Pazemes ūdeņu pamatmonitorings, 2004. gads . Latvijas vides, ģeoloģijas un meteoroloģijas aģentūra, Rīga, 2005. 42 lpp. 17. Schneider, R. Correlation of groundwater levels and air temperatures in the winter and spring in Minnesota . Minnesota Division of Waters, 1961, vol. 1, p. 219-228. 18. Wu, J., Zhang, R. Analysis of rainfall-infiltration recharge to groundwater. In: Proceedings of Fourteenth Annual American Geophysical Union

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Assessing the suitability of extreme learning machines (ELM) for groundwater level prediction

References ACHARYA N., SHRIVASTAVA N.A., PANIGRAHI B.K., MOHANTY U.C. 2014. Development of an artificial neural network based multi-model ensemble to estimate the northeast monsoon rainfall over south peninsular India: an application of extreme learning machine. Climate Dynamics. Vol. 43. Iss. 5-6 p. 1303-1310. ADAMOWSKI J., CHAN H.F. 2011. A wavelet neural network conjunction model for groundwater level forecasting. Journal of Hydrology. Vol. 407. Iss. 1 p. 28-40. ALLEN D.M., STAHL K., WHITFIELD P.H., MOORE R

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Development of groundwater levels as a consequense of climate change

Development of groundwater levels as a consequense of climate change

Climate change poses a significant threat to many wetland ecosystems. Wetlands exist in a transition zone between aquatic and terrestrial environments and can be affected by slight alterations in regional hydrology, which can influence climate change through air temperature changes, regional changes in a rainfall regime, surface run-off, snow, duration of the winter season, groundwater resources and evapotranspiration.

Climate change in wetland areas is most significantly reflected in water levels and adjacent groundwater levels, and it can significantly change the hydroecological proportions of wetland ecosystems and endanger rare wetland fauna and flora communities. The focus of this paper is the impact of climate change on the groundwater level in the Záhorie Protected Landscape area in the Zelienka national nature reservation. The impact of the climate change was solved through the meteorological characteristic changes adapted by the GISS98 and CCCM2000 climatic scenarios. The groundwater level was determined by the HYDRUS-ET model for the time frames 2010, 2030 and 2075 in 20-year time intervals and consequently compared to the reference period of 1971-1990.

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The Advantages of Using Sequential Stochastic Simulations when Mapping Small-Scale Heterogeneities of the Groundwater Level

Abstract

In the environmental risk assessment of oil fields, a detailed knowledge of the heterogeneity of groundwater surfaces is absolutely indispensable. Based on theoretical considerations, in order to analyse small-scale heterogeneities, we decided that the Sequential Gaussian Simulation (SGS) approach seemed to be the most appropriate one. This method gives preference to the reproduction of small-scale heterogeneities at the expense of local accuracy. To test whether this kind of heterogeneity of the groundwater level corresponds to sedimentological variability, a point bar of the River Tisza (South-Hungary) was chosen. In variograms, the longest range was derived from the large-scale sedimentological heterogeneity of the point-bar, the medium range was in accordance with the radius of the meander and its direction coincided with the depositional strike of the meander, while the shortest range corresponded to the lateral heterogeneity of the deposits where the ground water level was measured. The similarities and differences of the realizations of SGS express the uncertainty of the map representation of the ground water surface. The E-type estimates of 100 equiprobable realizations resulted in a very detailed surface. The hydraulic gradient map obtained from the E-type estimates can provide us with a better understanding of the local flow characteristics.

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The effects of uninsulated sewage tanks on groundwater. A case study in an eastern Hungarian settlement

the groundwater level]. Theory meets practice in GIS VII. p. 311–317. M ichéli E., F uchs M., H egymegi P., S tefanovits P. 2006. Classification of the major soils of Hungary and their correlation with the World Reference Base for Soil Resources (WRB). Agrochemistry and Soil Science. Vol. 55. Iss. 1 p. 19–28. MSZ-21464:1998. Mintavétel a felszín alatti vizekből [Sampling of groundwaters]. M üller H.W., D ohrmann R., K losa D., R ehder S., W olf E ckelmann W. 2009. Comparison of two procedures for particle-size analysis: Köhn pipette and X

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The impact of climate change on the annual variation of shallow groundwater levels in Latvia

References 1. Bergström, S. 1995. The HBV model. In: Singh, V.P. (eds.), Computer Models of Watershed Hydrology. Water resources publications, Highlands Ranch, CO., 443-476. 2. Chelmicki, W. 1993. The annual regime of shallow groundwater levels in Poland. Ground Water. 31(3), 383-388. 3. Draveniece, A. 2007. Okeāniskās un kontinentālās gaisa masas Latvijā. Latvijas Veģetācija, 14, 135. 4. Doe, W., W., Saghafian, B., Julien, P. 1996. Land-Use Impact On Watershed Response: The

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Landscape degradation at different spatial scales caused by aridification

of the Danube-Tisza Interfluve. Theses of the PhD Doctoral Dissertation, Budapest, Eötvös Loránd University. KUTI, L., VATAI, J., MÜLLER, T., KERÉK, B. (2002): Change of the groundwater level on the Danube-Tisza Hilly Region. Földtani Közlöny 132 (Special Issue): 317–325. LADA (2016): Field Manual for Local Level Land Degradation Assessment in Drylands. LADA-L Part 1: Methodological Approach, Planning and Analysis. Rome, FAO. LADÁNYI, Z., RAKONCZAI, J., DEÁK, J. Á. (2011a): A Hungarian landscape under strong natural and human impact in the last

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Changes of soil water regime types in the area adjacent to the Tomisławice open-cast lignite mine (central Poland)

Abstract

This work presents the results of a four-year study on the determination of the range of soil groundwater drainage caused by the operation of the Tomisławice lignite open-cast mine. The performed analyses covered the area of 9600 ha which included 24 villages. It was found that operation of Tomisławice open-cast mine caused noticeable changes of soil groundwater level in the areas adjacent to the excavation. It consequently resulted in considerable changes in soil water regimes types on grassland areas but it did not always lead to soil degradation processes. However, the deterioration of soils hydrological conditions may cause disappearance of certain hydrophilous grass species.

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Diagnosis Of The Impact Of The Gabčíkovo Water Project On Soil Water Regime In The Surroundings

Abstract

Rye Island is a unique natural formation, which lies between the main flow of the Danube River and the Little Danube River and is the largest river island in Europe. It is located in the southwest of Slovakia and with its mild to slightly warm climate is one of the most fertile agricultural areas in Slovakia. The whole Rye Island is also our greatest reservoir of quality waters used for drinking purposes, where groundwaters of Rye Island are permanently supplied with water from the Danube River. It means that as water levels in the Danube River were unstable before the construction of the Gabčíkovo Water Project, also the groundwater level faced large fluctuations. Changes occurred after putting the Gabčíkovo Water Project into service, with a decrease in groundwater levels. Thereby, the conditions for agriculture have improved and drying of surrounding protected floodplain forests has stopped. Through the present contribution we decided to analyse the impact of Gabčíkovo on soil water regime in the area of Rye Island, and evaluate the course of groundwater level, precipitation and soil water storage over time. For the representative area we chose a forest ecosystem of Král’ovská Lúka and evaluated the period 1999 to 2009.

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Assessment of the impact of the Odra river water levels on groundwater levels in Rzeczyca region

Abstract

Groundwater table levels in a river valley depend, among other factors, on meteorological and hydrogeological conditions, land use and water levels in watercourses. The primary role of a watercourse is to collect surface and groundwater, and it becomes an infiltrating watercourse at high water levels. Changes in groundwater levels and the range of these changes depend chiefly on the shape, height and duration of the flood wave in the river channel.

The assessment of flood wave impact on groundwater was based on long-term measurements of groundwater levels in the Odra valley and observations of water levels in the river channel. Simulations were performed with the use of in-house software FIZ (Filtracja i Zanieczyszczenia; Filtration and Contamination), designed for modelling unsteady water flows within a fully saturated zone. A two-dimensional model with two spatial variables was employed. The process of groundwater flow through a porous medium, non-homogeneous in terms of water permeability, was described with Boussinesq equation. The equation was solved with the use of finite element method. The model was applied to assess groundwater level fluctuations in the Odra valley in the context of actual flood waves on the river.

Variations in groundwater table in the valley were analysed in relation to selected actual flood water levels in the Odra in 2001-2003 and 2010. The period from 2001 to 2003 was used to verify the model. A satisfactory agreement between the calculated and the measured values was obtained. Based on simulation calculations, it was proved that flood waves observed in 2010 caused a rise in groundwater table levels in a belt of approximately 1000 metres from the watercourses. It was calculated that at the end of hydrological year 2009/2010, the highest growths, of up to 0.80 m, were observed on piezometers located close to the Odra river channel. The passage of several flood waves on the Odra caused an increase of subsurface retention by 3.0% compared to the initial state.

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