The dynamics of cultivation and floods in arable lands of Central Argentina

Abstract. Although floods in watersheds have been associated with land-use change since ancient times, the dynamics of flooding is still incompletely understood. In this paper we explored the relations between rainfall, groundwater level, and cultivation to explain the dynamics of floods in the extremely flat and valuable arable lands of the Quinto river watershed, in central Argentina. The analysis involved an area of 12.4 million hectare during a 26-year period (1978–2003), which comprised two extensive flooding episodes in 1983–1988 and 1996–2003. Supported by information from surveys as well as field and remote sensing measurements, we explored the correlation among precipitation, groundwater levels, flooded area and land use. Flood extension was associated to the dynamics of groundwater level. While no correlation with rainfall was recorded in lowlands, a significant correlation (P<0.01) between groundwater and rainfall in highlands was found when estimations comprise a time lag of one year. Correlations between groundwater level and flood extension were positive in all cases, but while highly significant relations (P<0.01) were found in highlands, non significant relations (P>0.05) predominate in lowlands. Our analysis supports the existence of a cyclic mechanism driven by the reciprocal influence between cultivation and groundwater in highlands. This cycle would involve the following stages: (a) cultivation boosts the elevation of groundwater levels through decreased evapotranspiration; (b) as groundwater level rises, floods spread causing a decline of land cultivation; (c) flooding propitiates higher evapotranspiration favouring its own retraction; (d) cultivation expands again following the retreat of floods. Thus, cultivation would trigger a destabilizing feedback self affecting future cultivation in the highlands. It is unlikely that such sequence can work in lowlands. The results suggest that rather than responding directly and solely to the same mechanism, floods in lowlands may be the combined result of various factors like local rainfall, groundwater level fluctuations, surface and subsurface lateral flow, and water-body interlinking. Although the hypothetical mechanisms proposed here require additional understanding efforts, they suggest a promising avenue of environmental management in which cultivation could be steered in the region to smooth the undesirable impacts of floods.

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The dynamics of cultivation and floods in arable lands of central Argentina

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-5-2319-2008 ◽

2008 ◽

Vol 5 (4) ◽

pp. 2319-2345 ◽

Cited By ~ 3

Author(s):

E. F. Viglizzo ◽

E. G. Jobbagy ◽

L. V. Carreño ◽

F. C. Frank ◽

R. Aragón ◽

...

Keyword(s):

Land Use ◽

Groundwater Level ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Reciprocal Influence ◽

Central Argentina ◽

Cyclic Mechanism ◽

Subsurface Lateral Flow ◽

Land Cultivation ◽

Flooded Area

Abstract. Although floods in watersheds have been associated with land-use change since ancient times, the dynamics of flooding is still incompletely understood. In this paper we explored the relations between rainfall, groundwater level, and cultivation to explain the dynamics of floods in the extremely flat and valuable arable lands of the Quinto river watershed, in central Argentina. The analysis involved an area of 12.4 million hectare during a 26-y period (1978–2003), which comprised two extensive flooding episodes in 1983–1988 and 1996–2003. Supported by information from surveys as well as field and remote sensing measurements, we explored the correlation among precipitation, groundwater levels, flooded area and land use. Flood extension was associated to the dynamics of groundwater level, but these two variables displayed a poor association with rainfall, being particularly decoupled from it during the rainy periods. Correlations between groundwater level and flood extension were positive in all cases, but while highly significant relations (P<0.01) were found in highlands, non significant relations (P>0.05) predominate in lowlands. Our analysis supports the existence of a cyclic mechanism driven by the reciprocal influence between cultivation and groundwater levels in highlands. This cycle would involve the following stages: (a) cultivation boosts the elevation of groundwater levels through decreased evapotranspiration; (b) as groundwater level rises, floods spread causing a decline of land cultivation; (c) flooding propitiates higher evapotranspiration favouring its own retraction; (d) cultivation expands following the retreat of floods. Thus, cultivation would trigger a destabilizing feedback self affecting future cultivation in the highlands. It is unlikely that such sequence can work in lowlands. The results suggest that rather than responding directly and solely to the same mechanism, floods in lowlands may be the combined result of various factors like local rainfall, groundwater level fluctuations, surface and subsurface lateral flow, and water-body interlinking. Although the hypothetical mechanisms proposed here require additional understanding efforts, they suggest a promising avenue of environmental management in which cultivation could be steered in the region to smooth the undesirable impacts of floods.

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The Role of Environmental Background Processes in Determining Groundwater Level Variability—An Investigation of a Record Flood Event Using Dynamic Factor Analysis

Water ◽

10.3390/w12092336 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2336

Author(s):

Balázs Trásy ◽

Norbert Magyar ◽

Tímea Havril ◽

József Kovács ◽

Tamás Garamhegyi

Keyword(s):

Factor Analysis ◽

Groundwater Level ◽

Coefficient Of Determination ◽

Dynamic Factor Analysis ◽

Dynamic Factor ◽

Climate Change Scenarios ◽

Background Factors ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Environmental Background

Since groundwater is a major source of water for drinking and for industrial and irrigation uses, the identification of the environmental processes determining groundwater level fluctuation is potentially a matter of great consequence, especially in light of the fact that the frequency of extreme climate events may be expected to increase, causing changes in groundwater recharge systems. In the recent study, data measured at a frequency of one hour were collected from the Szigetköz, an inland delta of the Danube. These were then used to determine the presence, or not, and magnitude of any hidden environmental background factors that may be causing groundwater level fluctuations. Through the application of dynamic factor analysis, it was revealed that changes in groundwater level are mainly determined by (i) the water level of neighboring rivers and (ii) evapotranspiration. The intensity of these factors may also be estimated spatially. If the background factors determined by dynamic factor analysis do indeed figure in the linear model as variables, then the time series of groundwater levels can be said to have been accurately estimated with the use of linear regression. The accuracy of the estimate is indicated by the fact that adjusted coefficient of determination exceeds 0.9 in 80% of the wells. The results, via an enhanced understanding of the reasons for changes in the fluctuation of groundwater, could assist in the development of sustainable water management and irrigation strategies and the preparation for varying potential climate change scenarios.

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Groundwater Modeling with Machine Learning Techniques: Ljubljana polje Aquifer

Proceedings ◽

10.3390/proceedings2110697 ◽

2018 ◽

Vol 2 (11) ◽

pp. 697 ◽

Cited By ~ 6

Author(s):

Klemen Kenda ◽

Matej Čerin ◽

Mark Bogataj ◽

Matej Senožetnik ◽

Kristina Klemen ◽

...

Keyword(s):

Machine Learning ◽

Groundwater Level ◽

Groundwater Modeling ◽

Machine Learning Techniques ◽

Physical Parameters ◽

Strongly Correlated ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Decision Making Processes ◽

Input Variables

In this study a thorough analysis is conducted concerning the prediction of groundwater levels of Ljubljana polje aquifer. Machine learning methodologies are implemented using strongly correlated physical parameters as input variables. The results show that data-driven modelling approaches can perform sufficiently well in predicting groundwater level changes. Different evaluation metrics confirm and highlight the capability of these models to catch the trend of groundwater level fluctuations. Despite the overall adequate performance, further investigation is needed towards improving their accuracy in order to be comprised in decision making processes.

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Wildfire Impacts on Groundwater Aquifers: A Case Study of the 1996 Honey Boy Fire in Beaver County, Utah, USA

Water ◽

10.3390/w13162279 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2279

Author(s):

Benjamin T. Johnk ◽

David C. Mays

Keyword(s):

Groundwater Level ◽

Temporary Reduction ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Monitoring Wells ◽

Groundwater Aquifers ◽

Before And After ◽

Beaver County ◽

Level Reduction

It is well known that wildfires destroy vegetation and form soil crusts, both of which increase stormwater runoff that accelerates erosion, but less attention has been given to wildfire impacts on groundwater aquifers. Here, we present a systematic study across the contiguous United States to test the hypothesis that wildfires reduce infiltration, indicated by temporary reductions in groundwater levels. Geographic information systems (GIS) analysis performed using structured queried language (SQL) categorized wildfires by their proximity to wells with publicly available monitoring data. Although numerous wildfires were identified with nearby monitoring wells, most of these data were confounded by unknown processes, preventing a clear acceptance or rejection of the hypothesis. However, this analysis did identify a particular case study, the 1996 Honey Boy Fire in Beaver County, Utah, USA that supports the hypothesis. At this site, daily groundwater data from a well located 790 m from the centroid of the wildfire were used to assess the groundwater level before and after the wildfire. A sinusoidal time series adjusted for annual precipitation matches groundwater level fluctuations before the wildfire but cannot explain the approximately two-year groundwater level reduction after the wildfire. Thus, for this case study, there is a correlation, which may be causal, between the wildfire and temporary reduction in groundwater levels. Generalizing this result will require further research.

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Modelling of the Complex Groundwater Level Dynamics during Episodic Rainfall Events of a Surficial Aquifer in Southern Italy

Water ◽

10.3390/w12102916 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2916

Author(s):

Nicola Pastore ◽

Claudia Cherubini ◽

Angelo Doglioni ◽

Concetta Immacolata Giasi ◽

Vincenzo Simeone

Keyword(s):

Groundwater Level ◽

Southern Italy ◽

Infiltration Rate ◽

Water Volume ◽

Rainfall Events ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Groundwater Supply ◽

Non Linear ◽

Surficial Aquifer

We analyzed the complex dynamics that are involved the groundwater level variations due to the episodic rainfall supply in the Ionian coastal plain surficial aquifer located in Southern Italy. In this aquifer, as a consequence of the particular hydrogeological framework, both direct and lateral recharge mechanisms coexist. Hence, the dynamics of groundwater level variations are quite complex and strongly non-linear. Our focus was essentially on the short-term behavior of groundwater levels, with a specific analysis on episodic rainfall events. To model these dynamics, due to the presence of the preferential pathways in the infiltration processes, a kinematic dispersion wave model was used. Specifically, a one-dimensional and non-linear particle-based numerical model was developed. It uses ideal particles with constant water volume travel, according to celerity and hydraulic dispersion, to simulate the infiltration rate wave through the vadose zone. The infiltration rate that reaches the water table represents the input function to evaluate the aquifer groundwater level fluctuations. As a consequence of the special lithological and storage capacity characteristics of the surficial layers, groundwater flow conditions change from unconfined to confined. The developed model analyzes the direct groundwater supply under natural conditions, including episodic rainfall, and it has been validated using a high-resolution time series of rainfall data and groundwater level obtained from the monitoring station Terra Montonata.

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The Effect Of Rainfall Relationship periode 2003 – 2013 Of Groundwater South Jakarta Region

Jurnal Lingkungan dan Bencana Geologi ◽

10.34126/jlbg.v11i3.301 ◽

2020 ◽

Vol 11 (3) ◽

pp. 125

Author(s):

Arini Dian ◽

Nana Sulaksana ◽

A. Asseggaf

Keyword(s):

Groundwater Level ◽

Rainy Season ◽

Rainfall Intensity ◽

Rainfall Event ◽

Clean Water ◽

Aquifer System ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Fine Grained ◽

Groundwater Basin

ABSTRAKKebutuhan air bersih di Jakarta sangat meningkat sehingga pemerintah daerah mulai melakukan pengamatan muka airtanah. Penelitian ini dilakukan dengan menganalisis fluktuasi muka airtanah pada AWLR, intensitas curah hujan, dan penampang bawah permukaan pada beberapa buah titik logbor selama tahun 2003 - 2013 di wilayah Jakarta Selatan. Jumlah curah hujan di daerah penelitian berkisar antara 0,2 - 831,4 mm/bulan. Dari data AWLR dapat diketahui ketinggian muka airtanah berkisar antara 9,29 - 13,97 m aml, terdangkal terjadi pada bulan Oktober - Febuari (ketika musim penghujan) dan ketinggian muka airtanah terdalam berkisar antara14,60 - 20,41 m aml terjadi pada bulan Maret - September (ketika musim kemarau). Penelitian ini dilakukan untuk mengidentifikasi adanya pengaruh hubungan curah hujan dan muka airtanah dengan karakteristik sistem akuifer yang berada pada daerah penelitian sekitarnya khususnya di Jakarta Selatan. Berdasarkan analisis tenggang waktu dan fluktuasi muka airtanah yang dipengaruhi oleh intensitas curah hujan.Serta adanya lapisan akuitar pada penampang geologi dan posisi muka airtanah yang terdapat dibagian atas lapisan akuifer, maka dapat dikatakan bahwa sistem akuifer yang terdapat di daerah penelitian bersifat semi tertekan. Sistem akuifer tersebut pada bagian atasnya merupakan material berbutir halus (akuitar) sehingga airtanah masih memungkinkan untuk bergerak di dalamnya.Kata kunci: airtanah, AWLR, curah hujan, fluktuasi, JakartaABSTRACTThe need for clean water in Jakarta has increased significantly, so the groundwater levels of Jakarta Groundwater Basin need to be researched. This research was conducted by analyzing the fluctuation of the groundwater level using the AWLR data, rainfall intensity, and subsurface sections to several logbor during the year of 2003 - 2013 in South Jakarta area. Rainfall event in the area is in range of 0.2 mm/year up to 831.4 mm/year. From the AWLR data, the highest groundwater level were at 9.29 - 13.97 masl in October - Febuari (during rainy season) and the deepest groundwater level were at 14.60 - 20.41 masl) in March - September (during dry season). Based on the analysis of the timescale and the groundwater level fluctuations that influenced by rainfall, and the aquitard layer in the geology section, and groundwater level exist above the aquifer, so that the aquifer system in this regions is classified as semi depressed aquifer. In this aquifer system, the underlying material is fine grained (aquitard) that allows groundwater moving inside the layer.Keywords: groundwater, AWLR, rainfall, fluctuation, Jakarta

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Analysis of groundwater levels in piezometers in the Vipava Valley

Acta hydrotechnica ◽

10.15292/acta.hydro.2020.05 ◽

2020 ◽

pp. 61-78

Author(s):

Mateja Jelovčan ◽

Mojca Šraj

Keyword(s):

Surface Water ◽

Water Level ◽

Groundwater Level ◽

Tectonic Structure ◽

Unique Region ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

The Third ◽

Autumn And Winter ◽

The Impact

The Vipava Valley is a unique region in south-western Slovenia. In addition to surface water, groundwater is also important, although it is hidden from the eye. The paper presents an analysis of groundwater levels in piezometers in the Vipava Valley. The analysis was performed on 10 piezometers, which are still operating today, and includes a display of levels and basic statistics, correlations, the impact of distance from the Vipava riverbed, trends, and seasonality. According to the groundwater level, piezometers in the Vipava Valley can be divided into three groups. The first group with the highest levels includes piezometers Gradišče, Vipavski Križ, and Ajdovščina, the second group piezometers Prvačina, Šempeter, Volčja Draga, Renče, and Vrtojba, and the third group with the lowest groundwater levels includes the piezometers Miren and Orehovlje. The results of the analyses showed good or bad connections between groundwater levels in piezometers, as well as between groundwater levels and the Vipava River water level at various gauging stations. The fluctuation of the groundwater level is conditioned by the distance from the Vipava riverbed and the area’s geological or tectonic structure. An unambiguous trend of groundwater levels cannot be determined. The seasonality of groundwater level fluctuations is not pronounced, but the highest values of groundwater levels occur in autumn and winter, and the lowest in summer.

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Effect of groundwater fluctuation, construction, and retaining system on slope stability of Avas Hill in Hungary

Open Geosciences ◽

10.1515/geo-2020-0294 ◽

2021 ◽

Vol 13 (1) ◽

pp. 1139-1157

Author(s):

Eslam M. Hemid ◽

Tamás Kántor ◽

Ahmed A. Tamma ◽

Mostafa A. Masoud

Keyword(s):

Slope Stability ◽

Groundwater Level ◽

Pore Water Pressure ◽

Water Pressure ◽

Slope Instability ◽

Negative Effects ◽

Destructive Effect ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

The Church

Abstract Landslides are one of the natural hazards, which have significant negative effects on both humans and the environment. Thus, slope stability analyses and stabilization processes are necessary to obviate or mitigate landslides. In this study, the effect of groundwater level fluctuations and the construction of a building (i.e., a recently built church) on slope stability was investigated on the eastern slope of the Avas Hill, at Miskolc, in Northeast Hungary. Soil movements and groundwater levels were monitored and geological and slope stability models were constructed. Furthermore, the possibility of constructing a retaining system was evaluated to minimize the detrimental effects of both groundwater level fluctuations and the construction of the church. The findings showed that the fluctuation in groundwater levels had a destructive effect on slope stability due to pore-water pressure, which decreased the soil strength of the slope and slope stability. On the other hand, the church added an external load onto the underlying soil leading to an increase in slope instability. Hence, we suggested constructing retaining structures such as gravity retaining walls to increase the soil shear strength and enhance slope stability in the long term.

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Land subsidence in the San Joaquin Valley, California, USA, 2007–2014

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-372-23-2015 ◽

2015 ◽

Vol 372 ◽

pp. 23-27 ◽

Cited By ~ 4

Author(s):

M. Sneed ◽

J. T. Brandt

Keyword(s):

Land Use ◽

Surface Water ◽

Land Subsidence ◽

Groundwater Level ◽

Land Surface ◽

Land Use Changes ◽

San Joaquin Valley ◽

Flood Hazards ◽

Groundwater Levels ◽

Measured Rate

Abstract. Rapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater pumping, groundwater-level declines, and land subsidence. Differential land subsidence has reduced the flow capacity of water-conveyance systems in these areas, exacerbating flood hazards and affecting the delivery of irrigation water. Vertical land-surface changes during 2007–2014 were determined by using Interferometric Synthetic Aperture Radar (InSAR), Continuous Global Positioning System (CGPS), and extensometer data. Results of the InSAR analysis indicate that about 7600 km2 subsided 50–540 mm during 2008–2010; CGPS and extensometer data indicate that these rates continued or accelerated through December 2014. The maximum InSAR-measured rate of 270 mm yr−1 occurred in the El Nido area, and is among the largest rates ever measured in the SJV. In the Pixley area, the maximum InSAR-measured rate during 2008–2010 was 90 mm yr−1. Groundwater was an important part of the water supply in both areas, and pumping increased when land use changed or when surface water was less available. This increased pumping caused groundwater-level declines to near or below historical lows during the drought periods 2007–2009 and 2012–present. Long-term groundwater-level and land-subsidence monitoring in the SJV is critical for understanding the interconnection of land use, groundwater levels, and subsidence, and evaluating management strategies that help mitigate subsidence hazards to infrastructure while optimizing water supplies.

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The Groundwater Drought Initiative (GDI): Analysing and understanding groundwater drought across Europe

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-383-297-2020 ◽

2020 ◽

Vol 383 ◽

pp. 297-305

Author(s):

Bentje Brauns ◽

Daniela Cuba ◽

John P. Bloomfield ◽

David M. Hannah ◽

Christopher Jackson ◽

...

Keyword(s):

Groundwater Level ◽

Large Scale ◽

Spatial Coherence ◽

Meteorological Drought ◽

Arid Environments ◽

Groundwater Levels ◽

Groundwater Level Fluctuations ◽

Continental Scale ◽

European Collaboration ◽

Groundwater Drought

Abstract. In Europe, it is estimated that around 65 % of drinking water is extracted from groundwater. Worryingly, groundwater drought events (defined as below normal groundwater levels) pose a threat to water security. Groundwater droughts are caused by seasonal to multi-seasonal or even multi-annual episodes of meteorological drought during which the drought propagates through the river catchment into the groundwater system by mechanisms of pooling, lagging, and lengthening of the drought signals. Recent European drought events in 2010–2012, 2015 and 2017–2018 exhibited spatial coherence across large areas, thus demonstrating the need for transboundary monitoring and analysis of groundwater level fluctuations. However, such monitoring and analysis of groundwater drought at a pan-European scale is currently lacking, and so represents a gap in drought research as well as in water management capability. To address this gap, the European Groundwater Drought Initiative (GDI), a pan-European collaboration, is undertaking a large-scale data synthesis of European groundwater level data. This is being facilitated by the establishment of a new network to co-ordinate groundwater drought research across Europe. This research will deliver the first assessment of spatio-temporal changes in groundwater drought status from ∼1960 to present, and a series of case studies on groundwater drought impacts in selected temperate and semi-arid environments across Europe. Here, we describe the methods used to undertake the continental-scale status assessment, which are more widely applicable to transboundary or large-scale groundwater level analyses also in regions beyond Europe, thereby enhancing groundwater management decisions and securing water supply.

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