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Modelamiento y evaluación de la intrusión marina en el acuífero Chilca, Lima / Modeling and analysis of seawater intrusion in the aquifer of Chilca, LimaZúñiga Calderón, María José, Galvez Infante, Abdul 23 October 2019 (has links)
La demanda de agua en Chilca ha aumentado considerablemente en la última década, debido al aumento de la población y el desarrollo económico en la zona, y a la falta de recursos hídricos disponibles en la cuenca. Esta situación ha incrementado la sobre explotación de los recursos hídricos subterráneos. Estudios actuales revisados arrojaron evidencias de la contaminación del agua extraída. Por lo tanto, esta investigación plantea determinar el grado de extensión de la intrusión marina en la zona costera de Chilca, Lima. Para tal efecto, se modela numéricamente el flujo del agua subterránea con MODFLOW, que incluyen parámetros hidrogeológicos e hidrodinámicos del acuífero. Asimismo, se representa la dinámica de la intrusión marina con el modelo numérico SEAWATER INTRUSION. Se utilizaron datos de cargas hidráulicas en una red de pozos desde el 2005 al 2014, los que se usaron para calibrar el modelo y realizar un análisis de sensibilidad. Con el modelo calibrado, se simuló la intrusión marina en 10, 20 y 40 años. Los resultados muestran que la extensión en longitud de la intrusión podría avanzar hasta 4350 m con respecto al litoral para el año 2057. / The water demand in Chilca has increased considerably in the last decade, due to the increase in population and economic development in the area, and the lack of available water resources in the basin. This situation has increased the overexploitation of groundwater resources. Current studies reviewed showed evidence of contamination of extracted water. Therefore, this research proposes to estimate the extent of the marine intrusion in the coastal zone of Chilca, Lima. For this purpose, first, the groundwater flow is represented using MODFLOW model, which include hydrogeological and hydrodynamic parameters of the aquifer. Second, the dynamics of the marine intrusion is represented with the numerical model SEAWATER INTRUSION. Hydraulics heads from 2005 to 2014 were used from a network wells, which were used to calibrate the model and perform a sensitivity analysis. With the calibrated model, the marine intrusion was simulated in 10, 20 and 40 year-periods. The results show that the extension in terms of length of the intrusion could advance up to 4350 m from the coast line by the year 2057. / Tesis
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Exploring the Soil-Plant-Atmosphere Continuum: Advancements, Integrated Modeling and Ecohydrological InsightsD'Amato, Concetta 31 May 2024 (has links)
In recent years, the Soil-Plant-Atmosphere (SPA) continuum has faced unprecedented challenges due to anthropogenic modifications and climate change. Understanding the complex dynamics of this system in response to such changes is crucial for addressing contemporary environmental concerns. Albert Einstein's famous quote, "The measure of intelligence is the ability to change", resonates deeply throughout this doctoral thesis. This thesis aims to address the complex issue of SPA interactions by developing a comprehensive set of models capable of representing the intricate dynamics of this system. At the core of this research lies the integration of sophisticated descriptions of hydrological and plant biochemical processes into a novel ecohydrological model, GEOSPACE-1D (Soil Plant Atmosphere Continuum Estimator model in GEOframe). Through a combination of theoretical exploration, engineering methodologies, and empirical experiments, this thesis aims to advance our understanding of SPA interactions. The development of adaptable models, represents a significant contribution to the field. The thesis emphasizes the practical implications of employing models to analyze experimental data, thereby enhancing our comprehension of various phenomena. In conclusion, this thesis provides valuable insights into SPA interactions and lays the groundwork for future research and applications. By embracing the challenge of understanding and modeling the SPA continuum, this work contributes to the ongoing efforts to address environmental challenges and promote sustainable practices.
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Srážko-odtokový proces v podmínkách klimatické změny / Rainfall runoff process in time of climate changeBenáčková, Kateřina January 2018 (has links)
The aim of The Diploma Thesis was to compile a conceptual rainfall-runoff model, that would be eligible to model discharge in conditions of climate changes. After thorough verifications of possible variants, user program Runoff Prophet that is eligible to simulate discharge in closing profile of any river basin was compiled within this paper. Runoff Prophet is deterministic lumped model with monthly computation time step and from the hydrologic phenomena it takes soil moisture, evapotranspiration, groundwater flow and the watercourse flow into account. Its calibration is based on the differential evolution principle with Nash–Sutcliffe model efficiency coefficient as the calibration criterion. Developed software was tested on Vír I. catchment basin and the results of this probe were evaluated from viewpoints of air temperature, precipitation and discharge characteristics in the Dalečín measurement river cross section in distant future according to A1B SRES climate scenario, implemented in LARS-WG weather generator.
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Analysis and Model-Based Assessment of Water Quality under Data Scarcity Conditions in two rural WatershedsLopes Tavares Wahren, Filipa Isabel 10 June 2020 (has links)
Pollution of surface and groundwater, due to improper land management, has become a major problem worldwide. Integrated watershed modelling provides a tool for the understanding of the processes governing water and matter transport at different scales within the watershed. The Soil Water Assessment Tool (SWAT) has been successfully utilized for the combined modelling of water fluxes and quality within a large range of scales and environmental conditions across the world. For suitable assessments integrated watershed models require large data sets of measured information for both model parameterization as for model calibration and validation. Data scarcity represents a serious limitation to the use of hydrologic models for supporting decision making processes, and may lead unsupported statements, poor statistics, misrepresentations, and, ultimately, to inappropriate measures for integrated water resources management efforts. In particular, the importance of spatially distributed soil information is often overlooked. In this thesis the eco-hydrological SWAT model was been applied to assess the water balance and diffuse pollution loadings of two rivers within a rural context at the mesoscale watershed level: 1) the Western Bug River, Ukraine, 2) the Águeda River, Portugal. Both watersheds in focus serve as examples for areas where the amount and quality of the measured data hinders a strait forward hydrologic modelling assessment. The Dobrotvir watershed (Western Bug River, Ukriane) is an example of such a region. In the former Soviet Union, soil classification primarily focused on soils of agricultural importance, whereas, forested, urban, industrial, and shallow soil territories were left underrepresented in the classification systems and resulting soil maps. Similarly the forest-dominated Águeda watershed in North-Central Portugal is a second example of a region with serious soil data availability limitations. Through the use of pedotransfer functions (PTFs) and the construction of soil-landscape models the data gaps could be successfully diminished, allowing a subsequent integrated watershed modelling approach. A valuable tool for the data gap closure was the fuzzy logic Soil Land Inference Model (SoLIM) which, combined with information from several soil surveys, was used to create improved maps. In the Dobrotvir watershed the fuzzy approach was used to close the gaps of the existing soil map, while in the Águeda watershed a new soil properties map, based upon the effective soil depths of the landscape, was constructed. While the water balance simulation in both study areas was successful, a calibration parameter ensemble approach was tested for the Águeda watershed. In the common modelling practice the individual best simulation and best parameter set is considered, the tested approach involved merging individual model outputs from numerous acceptable parameter sets, tackling the problematic of parameter equifinality. This procedure was tested for both original soil map and the newly derived soil map with differentiation of soil properties. It was noticeable that a better model set-up, with a better representation of the soil spatial distribution, was reflected in tighter model output spreads and narrower parameter distances. A further challenge was the calibration of water quality parameters, namely nitrate-N in the Dobrotvir watershed and sediment loads in the Águeda watershed. The limited amount of water quality observations were handled by assessing and by process verification at the smallest modelling unit, the hydrological response unit (HRU). The ruling hydrological processes could be depicted by combining own measured data and modelling outputs. The management scenario simulations showed the anticipated response to changes in management and reflected the rational spatial variation within the watershed reasonably well. The impacts of the different intervention options were evaluated on water balance, nitrate-N export and sediment yield at the watershed, sub-watershed and, when feasible, HRU level. This thesis covers two regional case studies with particular data limitations and specific processes of water and matter fluxes. Still, data reliability is a problem across the globe. This thesis demonstrates how relevant it is to tackle shortages of spatially differentiated soil information. The considered approaches contribute toward more reliable model predictions. Furthermore, the tested methods are transferable to other regions with differing landscape and climate conditions with similar problems of data scarcity, particularly soil spatially differentiated information.
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Hydrological and hydro-geological model of the Western Dead Sea catchment, Israel and West BankSachse, Agnes Christiane Felicia 01 April 2016 (has links)
Groundwater is the only fresh water resource in the semi-arid to hyper-arid Western Dead Sea catchment. Due to exploitation of groundwater the water level is decreasing in the surrounding Cretaceous aquifer system and sustainable water management is needed in order to prevent the progressive yields and contamination of those water resources. In addition, the water level of the Dead Sea decreases dramatically by at least one meter per year. This is connected to channel off the water from the Jordan River to supply intensive agriculture in the semi-arid to hyper-arid region.
Hydrological and hydro-geological analysis and modelling in arid regions, like the study area, frequently suffer from data scarcity and uncertainties regarding rainfall and discharge measurements. The study showed that spatial and temporal interpolations as well as additional methods (e.g. empirical relationships and simultaneous numerical approaches) were suitable tools to overcome data shortage for modelling.
Water balances are the result of a calibrated model and are the basis for sustainable management of surface and subsurface water resources. The present study investigates beside the hydrological characterisation of selected sub-catchments (wadis) also the hydro-geology of the Judean limestone aquifer and calculates a comprehensive water balance of the entire western flank of the Dead Sea by the application of two numerical open source codes: OpenGeoSys (OGS) and J2000g.
The calibrated two-dimensional hydrological model J2000g provides a 33 years time series of temporal and spatial distributed groundwater recharge for the numerical groundwater flow model of OGS. The mean annual groundwater recharge of 139.9 · 10^6 m^3ˑ a^-1 is nearly completely depleted by abstractions from pumping wells close to the replenishment area in the Judea Mountains.:Acknowledgements
Abstract
Nomenclature
Content
List of Figures
List of Tables
1 Introduction
1.1 Motivation
1.2 State of the Field
1.3 General research questions
1.4 Challenges
1.5 Structure of the Thesis
2 Theory and Methods
2.1 Data analysis
2.2 Governing equations
2.2.1 Surface Flow - Hydrological Model: J2000g
2.2.2 Subsurface Flow - Groundwater Flow Model: OpenGeoSys
2.3 Groundwater recharge
3 Study area
3.1 Study site selection
3.2 Geography
3.2.1 Climate
3.2.2 Soils
3.2.3 Vegetation
3.2.4 Land use
3.3 Hydrology
3.3.1 Wadis
3.3.2 Flashfloods
3.3.3 Dead Sea
3.4 Geology
3.5 Hydro-geology
3.5.1 Springs
3.5.2 Well fields
4 Hydrological Model
4.1 Conceptual Model
4.2 Hydrological Model J2000g
4.2.1 Data base
4.2.2 Simulation results from J2000g
5 Structural geological model
5.1 Stratigraphy
5.2 Database
5.3 Workflow
6 Numerical groundwater flow model
6.1 Work flow of 2D and 3D meshing
6.2 Parametrisation
6.3 Boundary conditions
6.4 Model Set-up
6.5 Calibration of Steady-State model
6.6 Transient Model
6.6.1 Model assumptions
6.6.2 Challenges
6.6.3 Preliminary results
7 Conclusions and Outlook
7.1 Important results from the hydrological model
7.2 Important results from the geological structural model
7.3 Important results from the hydro-geological model
7.4 Deficiencies
7.5 Outlook
References
8 Enclosed Publications
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