Spatial variability of chloride deposition in a vegetated coastal area: Implications for groundwater recharge estimation

Bresciani, Étienne; Ordens, Carlos M.; Werner, Adrian D.; Batelaan, Okke; Guan, Huade; Post, Vincent

doi:10.1016/j.jhydrol.2014.08.050

Cited by 48 publications

(26 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Knowledge of atmospheric chloride deposition is a prerequisite for applying this method, which is never straightforward given a range of processes that control atmospheric deposition [16][17][18][19] as they fluctuate temporally and are spatially variable, which makes extrapolating point measurements difficult. This has often been recognized as the main source of uncertainty when applying the CMB method [6,15,20,21], along with the right evaluation of the chloride concentration of recharge water [5]. Long-term average CMB data taken at different points are necessary to estimate long-term average recharge values.…”

Section: Introductionmentioning

confidence: 99%

Estimating Natural Recharge by Means of Chloride Mass Balance in a Volcanic Aquifer: Northeastern Gran Canaria (Canary Islands, Spain)

Naranjo

Cruz-Fuentes

Cabrera

et al. 2015

Water

View full text Add to dashboard Cite

Abstract:The chloride mass balance method was used to estimate the average diffuse groundwater recharge on northeastern Gran Canaria (Canary Islands), where the largest recharge to the volcanic island aquifer occurs. Rainwater was sampled monthly in ten rainwater collectors to determine the bulk deposition rate of chloride for the 2008-2014 period. Average chloride deposition decreases inwardly from more than 10 g·m . The application of the chloride mass balance method resulted in an estimated average recharge of about 28 hm 3 /year or 92 mm/year (24% of precipitation) in the study area after subtracting chloride loss with surface runoff. The average storm runoff was estimated to be 12 hm 3 /year (9% of precipitation) for the 1980-2014 period. Runoff was sampled during scarce rainy periods, which produce surface water flow. Average recharge varies from less than a few mm/year near the coast up to 270 mm/year in the highlands (about 33% of average rainfall), with a close-to-linear increase inwardly of about 18 mm·year. Recharge rate uncertainty corresponds to an estimated CV of 0.3-0.4 because of the short data series available.

show abstract

Section: Introductionmentioning

confidence: 99%

Estimating Natural Recharge by Means of Chloride Mass Balance in a Volcanic Aquifer: Northeastern Gran Canaria (Canary Islands, Spain)

Naranjo

Cruz-Fuentes

Cabrera

et al. 2015

Water

View full text Add to dashboard Cite

show abstract

“…Thus, in many environments, the Cl concentration can be assumed to remain equal to that of recharge along the groundwater flowpaths (if the effects of dispersion can be neglected (e.g. Bresciani et al, 2014)). …”

Section: Using Chloridementioning

confidence: 99%

“…Cl in groundwater originates from atmospheric deposition, of which the rate depends on a number of factors including distance to the source (oceanic or terrestrial), elevation, terrain aspect, slope, vegetation cover and climatic conditions (Hutton and Leslie, 1958;Guan et al, 2010;Bresciani et al, 2014). Groundwater Cl concentrations also depend on evapotranspiration, which leaves Cl in solution, implying its enrichment (Eriksson and Khunakasem, 1969), and on the spatial redistribution of recharge through groundwater flow.…”

Section: Using Chloridementioning

confidence: 99%

Using hydraulic head, chloride and electrical conductivity data to distinguish between mountain-front and mountain-block recharge to basin aquifers

Bresciani¹,

Cranswick²,

Banks³

et al. 2017

Preprint

View full text Add to dashboard Cite

Abstract. Numerous basin aquifers in arid and semi-arid regions of the world derive a significant portion of their recharge from adjacent mountains. Recharge can effectively occur through either stream infiltration in the mountain front zone (mountain-front recharge, MFR) or subsurface flow from the mountain (mountain-block recharge, MBR). While a thorough understanding of the recharge mechanisms is critical for water resource management, distinguishing between MFR and 15 MBR is typically difficult. Here we present a relatively simple approach that uses hydraulic head, chloride and electrical conductivity data to distinguish between MFR and MBR. These types of data are inexpensive to measure, and in many cases are readily available from hydrogeological databases. In principle, hydraulic head can inform on groundwater flow directions and stream-aquifer interactions, while chloride can help to distinguish between different groundwater pathways if the sources have distinct concentrations. Electrical conductivity values can be converted to chloride concentrations using an empirical 20 relationship, and hence can be used in a similar manner to chloride, thereby significantly increasing the data set. The practical feasibility and effectiveness of this approach are tested through the case study of the Adelaide Plains basin, South Australia, for which a wealth of historical groundwater level, chloride and electrical conductivity data is available. Hydraulic head data suggest that streams are gaining in the adjacent Mount Lofty Ranges and losing when entering the basin. They also indicate that not only the Quaternary sediments but also the underlying Tertiary sediments receive significant recharge from 25 stream leakage in the mountain front zone. Chloride data also reveal clear spatial patterns suggesting that MFR dominates recharge of the low salinity groundwater found in the basin. This interpretation is further supported by stream water chloride analysis. This study demonstrates that both hydraulic head and chloride data can be effectively used to distinguish between MFR and MBR.Hydrol. Earth Syst. Sci. Discuss., https://doi

show abstract

“…Additionally, these results highlight that vegetation are able to extract significant amounts of water from the unsaturated zone in Uley South [11], arguably in contradiction to Somaratne's [1] sinkhole concepts of point recharge that essentially bypasses the vadose zone. A recent investigation into vegetation influences on chloride loads to Uley South [17] demonstrated high variability in chloride loads to the land surface due to the chloride-capture effects of Uley South vegetation. The implications for CMB estimates of groundwater recharge were found to be significant, although further evaluation of vegetation stand "edge effects" are needed to narrow uncertainty bounds on revisions to CMB-based Uley South recharge [17].…”

Section: Somaratne [1] Cites Martin Et Al'smentioning

confidence: 99%

“…A recent investigation into vegetation influences on chloride loads to Uley South [17] demonstrated high variability in chloride loads to the land surface due to the chloride-capture effects of Uley South vegetation. The implications for CMB estimates of groundwater recharge were found to be significant, although further evaluation of vegetation stand "edge effects" are needed to narrow uncertainty bounds on revisions to CMB-based Uley South recharge [17]. These factors add to the challenges of quantifying the total chloride load to the land surface (i.e., computing both wet and dry deposition) in applying the CMB approach [18].…”

Section: Somaratne [1] Cites Martin Et Al'smentioning

confidence: 99%

Karst Aquifer Recharge: Comments on Somaratne, N. Characteristics of Point Recharge in Karst Aquifers. Water 2014, 6, 2782–2807

Werner

2014

Water

View full text Add to dashboard Cite

Abstract:The article "Characteristics of Point Recharge in Karst Aquifers, Water 6: 2782-2807" by N. Somaratne evaluates various recharge estimation techniques applied to four limestone aquifers in South Australia. Somaratne [1] concludes that methods based on watertable fluctuations, groundwater modelling and water budgets are independent of recharge processes, and are therefore superior to the chloride mass balance (CMB) approach for karst aquifers. The current comment offers alternative interpretations from existing field measurements and previous literature, in particular for the Uley South aquifer, which is the focus of much of the article by Somaratne [1]. Conclusions regarding this system are revised, partly to account for the misrepresentation of previous studies. The aeolianite sediments of Uley South are mostly unconsolidated or poorly consolidated, and dissolution features in the calcrete capping provide point infiltration into a predominantly unconsolidated vadose zone, whereas Somaratne's [1] findings require that the system comprises well-developed conduits in otherwise low-conductivity limestone. Somaratne's [1] assertion that the basic premise of CMB is violated in Uley South is disputable, given strong evidence of relatively well-mixed groundwater arising from mostly diffuse recharge. The characterization of karst aquifer recharge should continue to rely on multiple techniques, including environmental tracers such as chloride.

show abstract

Spatial variability of chloride deposition in a vegetated coastal area: Implications for groundwater recharge estimation

Cited by 48 publications

References 55 publications

Estimating Natural Recharge by Means of Chloride Mass Balance in a Volcanic Aquifer: Northeastern Gran Canaria (Canary Islands, Spain)

Estimating Natural Recharge by Means of Chloride Mass Balance in a Volcanic Aquifer: Northeastern Gran Canaria (Canary Islands, Spain)

Using hydraulic head, chloride and electrical conductivity data to distinguish between mountain-front and mountain-block recharge to basin aquifers

Karst Aquifer Recharge: Comments on Somaratne, N. Characteristics of Point Recharge in Karst Aquifers. Water 2014, 6, 2782–2807

Contact Info

Product

Resources

About