scholarly journals Reliability of recharge rates estimated from groundwater age with a simplified analytical approach

2021 ◽  
Author(s):  
Yanhui Dong ◽  
Yueqing Xie ◽  
Jun Zhang ◽  
Andrew J. Love ◽  
Xin Dai
Keyword(s):  
Analytical Approach ◽  
Groundwater Age ◽  
Recharge Rates

scholarly journals Reliability of recharge rates estimated from groundwater age with a simplified analytical approach

2020 ◽  
Author(s):  
Yanhui Dong ◽  
Yueqing Xie ◽  
Jun Zhang ◽  
Andy Love ◽  
Xin Dai
Keyword(s):  
Groundwater Recharge ◽  
Analytical Approach ◽  
Groundwater Age ◽  
Sampling Point ◽  
Flux Boundary Condition ◽  
Point Of Entry ◽  
Flux Boundary Conditions ◽  
The Mean ◽  
Recharge Rates

Groundwater age is often used to estimate groundwater recharge through a simplified analytical approach. This estimated recharge is thought to be representative of the mean recharge between the point of entry and the sampling point. However, given the complexity in actual recharge, whether the mean recharge is reasonable is still unclear. This study examined the validity of the method to estimate long-term average groundwater recharge and the possibility of obtaining reasonable spatial recharge pattern. We first validated our model in producing reasonable age distributions using a constant flux boundary condition. We then generated different flow fields and age patterns by using various spatially-varying flux boundary conditions with different magnitudes and wavelengths. Groundwater recharge was estimated and analyzed afterwards using the method at the spatial scale. We illustrated the main findings with a field example in the end. Our results suggest that we can estimate long-term average groundwater recharge with 10% error in many parts of an aquifer. The size of these areas decreases with the increase in both the amplitude and the wavelength. The chance of obtaining a reasonable groundwater recharge is higher if an age sample is collected from the middle of an aquifer and at downstream areas. Our study also indicates that the method can also be used to estimate local groundwater recharge if age samples are collected close to the water table. However, care must be taken to determine groundwater age regardless of conditions.

Renewed thinking on groundwater age

2021 ◽  
Author(s):  
Grant Ferguson ◽  
Mark Cuthbert ◽  
Kevin Befus ◽  
Tom Gleeson ◽  
Chandler Noyes ◽  
...  
Keyword(s):  
Environmental Flows ◽  
Numerical Models ◽  
Groundwater Age ◽  
Holistic Approach ◽  
Water Levels ◽  
Residence Times ◽  
Groundwater Sustainability ◽  
Long Time ◽  
Mean Residence Times ◽  
Recharge Rates

<p>Groundwater age and mean residence times have been invoked as measures of groundwater sustainability, with the idea that old or "fossil" groundwater is non-renewable. This idea appears to come from the link between groundwater age and background recharge rates, which are also of questionable use in assessing the sustainability of groundwater withdrawals. The use of groundwater age to assess renewability is further complicated by its relationship with flow system geometry. Young groundwaters near recharge areas are not inherently more renewable than older groundwaters down gradient. Similarly, there is no reason to preferentially use groundwater from smaller aquifers, which will have smaller mean residence times than larger aquifers for the same recharge rate. In some cases, groundwater ages may provide some information where groundwater recharge rates were much higher in the past and systems are no longer being recharged. However, there are few examples where the relationship between depletion and changes in recharge over long time periods has been rigorously explored. Groundwater age measurements can provide insights into the functioning of groundwater flow systems and calibration targets for numerical models and we advocate for their continued use, but they are not a metric of sustainable development. Simple metrics to assess groundwater sustainability remain elusive and a more holistic approach is warranted to maintain water levels and environmental flows.</p>

scholarly journals Regional Isotopic Signatures of Groundwater in Croatia

Water ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1983 ◽  
Author(s):  
Željka Brkić ◽  
Mladen Kuhta ◽  
Tamara Hunjak ◽  
Ozren Larva
Keyword(s):  
Stable Isotopes ◽  
Groundwater Age ◽  
Dinaric Karst ◽  
Isotopic Signatures ◽  
Carbonate Aquifers ◽  
Groundwater Samples ◽  
Tracer Methods ◽  
Recharge Rates ◽  
Northern Croatia ◽  
Isotope Content

Tracer methods are useful for investigating groundwater travel times and recharge rates and analysing impacts on groundwater quality. The most frequently used tracers are stable isotopes and tritium. Stable isotopes of oxygen (δ18O) and hydrogen (δ2H) are mainly used as indicators of the recharge condition. Tritium (3H) is used to estimate an approximate mean groundwater age. This paper presents the results of an analysis of stable isotope data and tritium activity in Croatian groundwater samples that were collected between 1997 and 2014 at approximately 100 sites. The composition of the stable isotopes of groundwater in Croatia originates from recent precipitation and is described using two regional groundwater lines. One of them is applied to groundwater accumulated in the aquifers in the Pannonian part of Croatia and the other is for groundwater accumulated in the Dinaric karst of Croatia. The isotope content shows that the studied groundwater is mainly modern water. A mix of sub-modern and modern water is mostly accumulated in semi-confined porous aquifers in northern Croatia, deep carbonate aquifers, and (sub)thermal springs.

A comparison of recharge rates in aquifers of the United States based on groundwater-age data

2011 ◽  
Vol 19 (4) ◽  
pp. 779-800 ◽  
Author(s):  
P. B. McMahon ◽  
L. N. Plummer ◽  
J. K. Böhlke ◽  
S. D. Shapiro ◽  
S. R. Hinkle
Keyword(s):  
United States ◽  
Groundwater Age ◽  
The United States ◽  
Recharge Rates

scholarly journals Assessing Decadal Trends of a Nitrate-Contaminated Shallow Aquifer in Western Nebraska Using Groundwater Isotopes, Age-Dating, and Monitoring

Water ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 1047 ◽  
Author(s):  
Martin Wells ◽  
Troy Gilmore ◽  
Aaron Mittelstet ◽  
Daniel Snow ◽  
Steven Sibray
Keyword(s):  
Groundwater Age ◽  
Small Region ◽  
The United States ◽  
Nitrate Contamination ◽  
Age Dating ◽  
Shallow Aquifer ◽  
United States Geological Survey ◽  
Biogeochemical Processes ◽  
Mean Values ◽  
Recharge Rates

Shallow aquifers are prone to nitrate contamination worldwide. In western Nebraska, high groundwater nitrate concentrations ([NO3−]) have resulted in the exploration of new groundwater and nitrogen management regulations in the North Platte Natural Resources District (NPNRD). A small region of NPNRD (“Dutch Flats”) was the focus of intensive groundwater sampling by the United States Geological Survey from 1995 to 1999. Nearly two decades later, notable shifts have occurred in variables related to groundwater recharge and [NO3−], including irrigation methods. The objective of this study was to evaluate how changes in these variables, in part due to regulatory changes, have impacted nitrate-contaminated groundwater in the Dutch Flats area. Groundwater samples were collected to assess changes in: (1) recharge rates; (2) biogeochemical processes; and (3) [NO3−]. Groundwater age increased in 63% of wells and estimated recharge rates were lower for 88% of wells sampled (n = 8). However, mean age and recharge rate estimated in 2016 (19.3 years; R = 0.35 m/year) did not differ significantly from mean values determined in 1998 (15.6 years; R = 0.50 m/year). δ15N-NO3− (n = 14) and dissolved oxygen data indicate no major changes in biogeochemical processes. Available long-term data suggest a downward trend in normalized [NO3−] from 1998 to 2016, and lower [NO3−] was observed in 60% of wells sampled in both years (n = 87), but median values were not significantly different. Collectively, results suggest the groundwater system is responding to environmental variables to a degree that is detectable (e.g., trends in [NO3−]), although more time and/or substantial changes may be required before it is possible to detect significantly different mean recharge.

The Dynamics of TAT Process

2014 ◽  
Vol 35 (2) ◽  
pp. 103-133 ◽  
Author(s):  
Benoît Verdon ◽  
Catherine Chabert ◽  
Catherine Azoulay ◽  
Michèle Emmanuelli ◽  
Françoise Neau ◽  
...  
Keyword(s):  
Defense Mechanisms ◽  
Analytical Approach ◽  
Therapeutic Process ◽  
Practice Research ◽  
Rorschach Test ◽  
Mental Functioning ◽  
Projective Tests ◽  
The Subject ◽  
Latent Content ◽  
Rigorous Method

After many years of clinical practice, research and the teaching of projective tests, Shentoub and her colleagues (Debray, Brelet, Chabert & al.) put forward an original and rigorous method of analysis and interpretation of the TAT protocols in terms of psychoanalysis and clinical psychopathology. They developed the TAT process theory in order to understand how the subject builds a narrative. Our article will emphasize the source of the analytical approach developed by V. Shentoub in the 1950s to current research; the necessity of marking the boundary between the manifest and latent content in the cards; the procedure for analyzing the narrative, supported by an analysis sheet for understanding the stories' structure and identifying the defense mechanisms; and how developing hypotheses about how the mental functions are organized, as well as their potential psychopathological characteristics; and the formulation of a diagnosis in psychodynamic terms. In conjunction with the analysis and interpretation of the Rorschach test, this approach allows us to develop an overview of the subject's mental functioning, taking into account both the psychopathological elements that may threaten the subject and the potential for a therapeutic process. We will illustrate this by comparing neurotic, borderline, and psychotic personalities.

Maxim Berezovsky C-dur symphony in a context of new biographical scenario of artist’s life-creativity

2018 ◽  
pp. 13-25
Author(s):  
Olha Shumilina
Keyword(s):  
Eighteenth Century ◽  
Instrumental Music ◽  
Analytical Approach ◽  
Spiritual Direction ◽  
Theoretical Research ◽  
Orchestral Music ◽  
Musical Life ◽  
Analysis And Synthesis ◽  
Mental Modeling ◽  
Independent Work

Relevance of the study. The article studies recently found symphony of the prominent Ukrainian composer of the second half of the eighteenth century Maxim Berezovsky. He is widely known now as the author of cyclic spiritual concerts written for the Orthodox worship, and is practically unknown as a musician instrumentalist associated with the imperial theater and the court musical life. The work of M. Berezovsky as a secular musician determined the creative interest in composing instrumental music intended for secular chamber and orchestral music. Main objective of the article is a clarification of M.Berezovsky symphony as one of secular field artworks in the light of new summaries about artist’s life-creativity. Methodology. Taking into account peculiarities of the material and the analytical approach to its study, the methods of theoretical research have been chosen(abstraction, analysis and synthesis, induction and deduction, mental modeling, ascension from abstract to concrete, etc.). Conclusions. As a result of a study the symphony analysis in a context of new authentic statements about M.Berezovsky’s life-creativity. It was stated that this artwork was written not accidentally and detects absolute awareness of the artist in all composer’s niceties – how to build a topic and build a homophonic construction based on it, in a technique of orchestral construction, form creations of that time and etc. From the beginning of his creative career, M. Berezovsky was well aware of the possibilities of the orchestra as a performer, attached to the Italian opera and instrumental music. Symphony enriches our imagination about the works of M. Berezovsky in the field of secular instrumental and operatic music and extends the range of works of the artist beyond the spiritual direction. Some signs indicate that the Symphony was not an independent work, but an overture to the opera Demofont.

Maxim Berezovsky C-dur symphony in a context of new biographical scenario of artist’s life-creativity

2018 ◽  
pp. 13-25
Author(s):  
Olha Shumilina
Keyword(s):  
Eighteenth Century ◽  
Instrumental Music ◽  
Analytical Approach ◽  
Spiritual Direction ◽  
Theoretical Research ◽  
Orchestral Music ◽  
Musical Life ◽  
Analysis And Synthesis ◽  
Mental Modeling ◽  
Independent Work

Relevance of the study. The article studies recently found symphony of the prominent Ukrainian composer of the second half of the eighteenth century Maxim Berezovsky. He is widely known now as the author of cyclic spiritual concerts written for the Orthodox worship, and is practically unknown as a musician instrumentalist associated with the imperial theater and the court musical life. The work of M. Berezovsky as a secular musician determined the creative interest in composing instrumental music intended for secular chamber and orchestral music. Main objective of the article is a clarification of M.Berezovsky symphony as one of secular field artworks in the light of new summaries about artist’s life-creativity. Methodology. Taking into account peculiarities of the material and the analytical approach to its study, the methods of theoretical research have been chosen(abstraction, analysis and synthesis, induction and deduction, mental modeling, ascension from abstract to concrete, etc.). Conclusions. As a result of a study the symphony analysis in a context of new authentic statements about M.Berezovsky’s life-creativity. It was stated that this artwork was written not accidentally and detects absolute awareness of the artist in all composer’s niceties – how to build a topic and build a homophonic construction based on it, in a technique of orchestral construction, form creations of that time and etc. From the beginning of his creative career, M. Berezovsky was well aware of the possibilities of the orchestra as a performer, attached to the Italian opera and instrumental music. Symphony enriches our imagination about the works of M. Berezovsky in the field of secular instrumental and operatic music and extends the range of works of the artist beyond the spiritual direction. Some signs indicate that the Symphony was not an independent work, but an overture to the opera Demofont.

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