Application of Isotopes and Recharge Analysis in Investigating Surface Water and Groundwater in Fractured Aquifer under Influence of Climate Variability

Nyende, Jacob; G, van Tonder; Vermeulen, Danie

doi:10.4172/2157-7617.1000148

Cited by 9 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many groundwater isotope compositions plot close to meteoric water lines, implying little if any evaporation occurs prior to recharge (e.g., Oman: Clark et al, ; Cameroon: Wirmvem, Ohba, et al, ). In other areas, δ 2 H and δ 18 O values plot below LMWLs, and evaporative isotope effects have likely impacted groundwater isotope compositions (Nyende et al, ). Groundwaters influenced by evaporative isotope effects are often identified by low deuterium excess values and δ 2 H/δ 18 O slopes of ~3 to ~6 (Figure ).…”

Section: Threshold Rainfall Intensities For Rechargementioning

confidence: 99%

Global Isotope Hydrogeology―Review

Jasechko

2019

Reviews of Geophysics

215

124

View full text Add to dashboard Cite

Groundwater 18O/16O, 2H/1H, 13C/12C, 3H, and 14C data can help quantify molecular movements and chemical reactions governing groundwater recharge, quality, storage, flow, and discharge. Here, commonly applied approaches to isotopic data analysis are reviewed, involving groundwater recharge seasonality, recharge elevations, groundwater ages, paleoclimate conditions, and groundwater discharge. Reviewed works confirm and quantify long held tenets: (i) that recharge derives disproportionately from wet season and winter precipitation; (ii) that modern groundwaters comprise little global groundwater; (iii) that “fossil” (>12,000‐year‐old) groundwaters dominate global aquifer storage; (iv) that fossil groundwaters capture late‐Pleistocene climate conditions; (v) that surface‐borne contaminants are more common in younger groundwaters; and (vi) that groundwater discharges generate substantial streamflow. Groundwater isotope data are disproportionately common to midlatitudes and sedimentary basins equipped for irrigated agriculture, but less plentiful across high latitudes, hyperarid deserts, and equatorial rainforests. Some of these underexplored aquifer systems may be suitable targets for future field testing.

show abstract

Section: Threshold Rainfall Intensities For Rechargementioning

confidence: 99%

Global Isotope Hydrogeology―Review

Jasechko

2019

Reviews of Geophysics

215

124

View full text Add to dashboard Cite

show abstract

“…A general mathematical explanation of the EARTH model derived from the equation of de Vries 1974 cited in [20] is given by [21], as follows:…”

Section: Satflow (Saturated Flow)mentioning

confidence: 99%

Impact of Climate Change on Groundwater Resources in the Klela Basin, Southern Mali

2016

View full text Add to dashboard Cite

Abstract:Investigations of groundwater resources in order to understand aquifer system behavior are vital to the inhabitants of the Klela Basin, Mali, because groundwater is the only permanent water resource and is used for drinking water and irrigation. Due to climate change, this vital resource is being threatened. Therefore, MODFLOW was applied in this study to simulate groundwater dynamics. The aim of this study was to evaluate the impact of climate change on groundwater resources in the Klela basin using the RCP4.5 (Representative Concentration Scenario 4.5 W/m 2 ) climate scenario. Climatological, geological, hydrogeological, hydraulic and demographic data were collected and used as model input data. Groundwater recharge was estimated to be approximately 165.3 mm/year using the EARTH (Extended model for Aquifer Recharge and soil moisture Transport through the unsaturated Hardrock) model. Recharge was then used as groundwater model input. The sandstone aquifer in the study area was simulated in steady and transient conditions. The results showed that hydraulic conductivity values varied from 1.1 to 13.9 m/day. The model was used for scenario quantification after model calibration and verification using three different piezometer data sets. The results of the simulated MODFLOW model showed a decrease in groundwater levels over time.

show abstract