Hydrogeochemical characteristics of groundwater influenced by reclamation, seawater intrusion, and land use in the coastal area of Yeonggwang, Korea

다국어 초록 (Multilingual Abstract)

The coastal line of Yeonggwang, South Korea, has been continuously changed by reclamation of tidal land to expand the residential and agricultural area, which is critical factor to understand the regional hydrogeochemistry in this area. In this study, we investigate the major factor to influence on the hydrogeochemical characteristics of groundwater in the reclaimed coastal area. Groundwaters from this area can be classified into four groups (A, B, C, and D) by a cluster analysis using their physico-chemical properties. Groups C and D have an enriched NO3– concentration (maximum ~210 mg/L), which is the result of anthropogenic inputs (particularly chemical fertilizers), whereas observations (e.g., high Cl–, Na+, and the correlation between Cl– and major anions/cations) have demonstrated that groups A and B are affected by old seawater intrusion. Agricultural activities also influence Group B because Br–/Cl– ratios vary, and values of the major cations/Cl– of this group are higher than those of seawater and Group A. The underlying organic matter and microbials have been influenced by the reclamation processes and the subsurface environment has experienced sudden changes, which have led to sub-/anoxic conditions that are sufficient to cause redox reactions. Because Mn and Fe reduction processes occur after NO3 reduction finishes, groups A and B have low Eh, dissolved oxygen (DO), and NO3– while they have high Fe2+, Mn2+, and HCO3– with depleted δ13CDIC. Furthermore, SO42– concentrations were very low compared to the estimated values from a simple two-component (seawater and freshwater) mixing model, with the enriched δ34SSO4 values (30.7~57.3‰) in these groups clearly demonstrating the occurrence of SO4 reduction. The reclamation process also appears to affect the recharge time of the regional groundwater system in the study area. Overall, the regional groundwater system in the coastal area of Yeonggwang has been influenced by the reclamation, old seawater intrusion, land use, and reduction process resulting in highly complicated hydrogeochemical characteristics.

참고문헌 (Reference)

1 Kim, J. -H., "Use of time series analysis for identification of tidal effect on groundwater in the coastal area of Kimje, Korea" 300 : 188-198, 2005

2 Strebel, O., "Use of isotope fractionation of sulfate-sulfur and sulfate-oxygen to asses bacterial desulfurication in a sandy aquifer" 121 : 155-172, 1990

3 Solomon, D. K., "Tritium and 3He as groundwater age tracers in the Borden Aquifer" 28 : 741-755, 1992

4 Groffman, A. R., "Transient redox regimes in a shallow alluvial aquifer" 161 : 415-442, 1999

5 Canfield, D. E., "Towards a consistent classification scheme for geochemical environments, or, why we wish the term ‘suboxic’ would go away" 7 : 385-392, 2009

6 Stuyfzand, P. J., "The impact of land reclamation on groundwater quality and future drinking water supply in the Netherlands" 32 : 47-57, 1995

7 Price, B. N., "The contrasting geochemical behaviors of iodine and bromine in resent sediments from the Nambian Shelf" 41 : 1769-1775, 1977

8 Canfield, D. E., "The anaerobic degradation of organic matter in Danish coastal sediments : Fe reduction, Mn reduction and sulfate reduction" 57 : 3867-3883, 1993

9 Helena, B., "Temporal evolution of ground water composition in an alluvial aquifer(Pisuerga River, Spain)by principal component analysis" 34 : 807-816, 2000

10 Yamanaka, M., "Sulfur isotope constraint on the provenance of salinity in a confined aquifer system of the southwestern Nobi Plain, central Japan" 325 : 35-55, 2006

11 APHA, "Standard Methods for the Examination of Water and Wastewater(19th edition)" American Public Health Association 1995

12 Böttcher, M. E., "Stable sulfur isotopes indicate net sulfate reduction in near sediment of the deep Arabian Sea" 47 : 2769-2783, 2000

13 Choi, B. Y., "Sources and biogeochemical behavior of nitrate and sulfate in an alluvial aquifer : hydrochemical and stable isotope approaches" 26 : 1249-1260, 2011

14 Koo, J. W., "Soil properties of reclaimed tidal lands and tidelands of western sea coast in Korea" 31 : 120-127, 1998

15 Kim, R. -H., "Salinization properties of a shallow groundwater in a coastal reclaimed area, Yeonggwang, Korea" 49 : 1180-1194, 2006

16 Bergelson, G., "Salinization and dilution history of groundwater discharging into the Sea of Galilee, the Dead Sea Transform, Israel" 14 : 91-118, 1999

17 Grobe, M., "Saline groundwater in the Münsterland Cretaceous Basin, Germany : clues to its origin and evolution" 19 : 307-322, 2002

18 Snyder, M., "Redox zonation at the saline-influenced boundaries of a permeable surficial aquifer : effects of physical forcing on the biogeochemical cycling of iron and manganese" 296 : 164-178, 2004

19 Genereux, D., "Quantifying uncertainty in tracer-based hydrograph separation" 34 : 915-919, 1998

20 Barker, A. P., "Processes affecting groundwater chemistry in a zone of saline intrusion into an urban sandstone aquifer" 13 : 735-749, 1998

21 Tuttle, M. L. W., "Process affecting δ34S and δ18O values of dissolved sulfate in alluvium along the Canadian River, central Oklahoma, USA" 265 : 455-467, 2009

22 Yanagisawa, F., "Precipitation of SO4 for sulfur isotope ratio measurement by thermal decomposition of BaSO4-V2O5-SiO2 mixtures" 55 : 985-987, 1983

23 Canfield, D. E., "Pathways of organic carbon oxidation in three continental margin sediments" 113 : 27-40, 1993

24 Yao, W., "Oxidation of hydrogen sulfide by hydrous Fe(III)oxides in seawater" 52 : 1-16, 1996

25 Cary, L., "Origins and processes of groundwater salinization in the urban coastal aquifers of Recife (Pernambuco, Brazil): a multi-isotope approach" 530-531 : 411-429, 2015

26 De Montety, V., "Origin of groundwater salinity and hydrogeochemical processes in a confined coastal aquifer : case of the Rhone delta(southern France)" 23 : 2337-2349, 2008

27 Louvat, D., "Origin and residence time of salinity in the Äspö groundwater system" 14 : 917-925, 1999

28 Canter, L. W., "Nitrate in Groundwater" Lewis Publisher 263-, 1997

29 Kim, J. -H., "Multivariate statistical analysis to identify the major factors governing groundwater quality in the coastal area of Kimje, South Korea" 19 : 1261-1276, 2005

30 Kuivila, K. M., "Methane cycling in the sediments of Lake Washington" 33 : 571-581, 1988

31 Wetzel, R. G., "Limnological Analalysis" Springer- Verlag 391-, 1991

32 Koh, D. -C., "Land-use controls on sources and fate of nitrate in shallow groundwater of an agricultural area revealed by multiple environmental tracers" 118 : 62-78, 2010

33 Samad, O. E., "Investigation of seawater intrusion using stable and radioisotopes at coastal area south of Beirut, the Capital of Lebanon" 76 : 187-, 2017

34 Barbecot, F., "Identification and characterization of a saline wedge in the Bajocian-Bathonian coastal aquifer of the area of Caen(France)" 326 : 539-544, 1998

35 Koh, D. -C., "Hydrogeochemistry and environmental isotopes of ground water in Jeju volcanic island, Korea : implications for nitrate contamination" 19 : 2225-2245, 2005

36 Kim, J. -H., "Hydrogeochemical characterization of major of shallow groundwater in the coastal area at Kimje in South Korea" 44 : 478-489, 2003

37 Jeen, S. -W., "Hydrogeochemical characteristics of groundwater in a mid-western coastal aquifer system, Korea" 4 : 339-348, 2011

38 Chae, G. -T., "Hydrochemical and stable isotopic assessment of nitrate contamination in an alluvial aquifer underneath a riverside agricultural field" 96 : 1819-1827, 2009

39 Cruz, J. V., "Groundwater salinization in Pico island(Azores, Portugal) : origin and mechanisms" 39 : 1181-1189, 2000

40 Chapple, F. H., "Ground Water Microbiology and Geochemistry" Wiley 424-, 1993

41 Appelo, C. A. J., "Geochemistry, Groundwater and Pollution" Balkeman 536-, 1993

42 Vengosh, A., "Geochemical and boron, strontium, and oxygen isotopic constraints on the origin of the salinity in groundwater from the Mediterranean coast of Israel" 35 : 1877-1894, 1999

43 Vítoria, L., "Fertilizer characterization : isotopic data(N, S, O, C, and Sr)" 38 : 3254-3262, 2004

44 Argamasilla, A., "Factors controlling groundwater salinization and hydrogeochemical processes in coastal aquifers from southern Spain" 580 : 50-68, 2017

45 Krouse, H. R., "Environmental Tracers in Subsurface Hydrology" Springer 195-231, 2000

46 Berner, R. A., "Early Diagenesis" Princeton University Press 241-, 1980

47 Lee, J., "Determination of groundwater flow regimes in underground storage caverns using tritium and helium isotopes" 63 : 763-770, 2011

48 Mehta, S., "Controls on the regionalscale salinization of the Ogallala aquifer, Southern High Plains, Texas, USA" 15 : 849-864, 2000

49 Vengosh, A., "Chloride/bromide and chloride/fluoride ratios of domestic sewage effluents and associated contaminated ground Water" 36 : 815-824, 1998

50 Nadler, A., "Chemical reactions of seawater with rocks and freshwater : experimental and field observations on brackish waters in Israel" 44 : 879-886, 1985

51 Elderfield, H., "Chemical diagnesis in Narragandett Bay sediments" 281 : 1021-1055, 1981

52 Vega, M., "Assessment of seasonal and polluting effects on the quality of river water by exploratory data analysis" 32 : 3581-3592, 1998