A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece)
Aquifer overexploitation in coastal aquifers has led to seawater intrusion that causes severe salinization effects on the groundwater system. The most widespread method for assessing groundwater vulnerability to seawater intrusion, the dominant cause of salinization in coastal aquifers, is the GALDI...
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MDPI AG
2022-11-01
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| Series: | Water |
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| Online Access: | https://www.mdpi.com/2073-4441/14/22/3689 |
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| author | Despina Chronidou Evangelos Tziritis Andreas Panagopoulos Efstathios K. Oikonomou Athanasios Loukas |
| author_facet | Despina Chronidou Evangelos Tziritis Andreas Panagopoulos Efstathios K. Oikonomou Athanasios Loukas |
| author_sort | Despina Chronidou |
| collection | DOAJ |
| description | Aquifer overexploitation in coastal aquifers has led to seawater intrusion that causes severe salinization effects on the groundwater system. The most widespread method for assessing groundwater vulnerability to seawater intrusion, the dominant cause of salinization in coastal aquifers, is the GALDIT method, with numerous applications globally. The present study proposes a modified version of the GALDIT method (GALDIT-Ι) to evaluate the vulnerability of salinization, including its potential additional sources. Both methods have been applied to Rhodope coastal aquifer, an intensively cultivated agricultural area subject to multiple salinization sources. The basic modifications of the proposed GALDIT-I method include different weighting factors and modification of classes for critical parameters, the use of a different indicator (TDS) for the estimation of the Impact factor and, overall, the address of the concept of groundwater salinization instead of seawater intrusion only. The differences in the results of the two methods were significant, as the modified version exhibited a more finite and realistic vulnerability capture, according to the area’s existing hydrogeological and hydrogeochemical knowledge. The original GALDIT method showed an area of nearly 80% as medium vulnerable with very limited spatial deviations. On the other hand, the proposed modified GALDIT method depicted high vulnerability hotspots away from the shoreline, indicating various salinity sources. The validation of the modified method showed that nearly 80% of the sampling points present very good to perfect match between the salinity assessment and the concentration of Cl<sup>−</sup>, indicating the successful validation of the method. Overall, the GALDIT-I method facilitated groundwater vulnerability assessment to salinization more accurately and exhibited a more discrete spatial assessment, thus, it could be regarded as a promising proactive tool for groundwater management and decision-making. |
| first_indexed | 2024-03-09T17:56:30Z |
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| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-09T17:56:30Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Water |
| spelling | doaj.art-bd01aab0e26b4940ad837d9f7af57d212023-11-24T10:21:23ZengMDPI AGWater2073-44412022-11-011422368910.3390/w14223689A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece)Despina Chronidou0Evangelos Tziritis1Andreas Panagopoulos2Efstathios K. Oikonomou3Athanasios Loukas4Soil and Water Resources Institute, ELGO-DIMITRA, 57001 Thessaloniki, GreeceSoil and Water Resources Institute, ELGO-DIMITRA, 57001 Thessaloniki, GreeceSoil and Water Resources Institute, ELGO-DIMITRA, 57001 Thessaloniki, GreeceSchool of Rural and Surveying Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, GreeceSchool of Rural and Surveying Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, GreeceAquifer overexploitation in coastal aquifers has led to seawater intrusion that causes severe salinization effects on the groundwater system. The most widespread method for assessing groundwater vulnerability to seawater intrusion, the dominant cause of salinization in coastal aquifers, is the GALDIT method, with numerous applications globally. The present study proposes a modified version of the GALDIT method (GALDIT-Ι) to evaluate the vulnerability of salinization, including its potential additional sources. Both methods have been applied to Rhodope coastal aquifer, an intensively cultivated agricultural area subject to multiple salinization sources. The basic modifications of the proposed GALDIT-I method include different weighting factors and modification of classes for critical parameters, the use of a different indicator (TDS) for the estimation of the Impact factor and, overall, the address of the concept of groundwater salinization instead of seawater intrusion only. The differences in the results of the two methods were significant, as the modified version exhibited a more finite and realistic vulnerability capture, according to the area’s existing hydrogeological and hydrogeochemical knowledge. The original GALDIT method showed an area of nearly 80% as medium vulnerable with very limited spatial deviations. On the other hand, the proposed modified GALDIT method depicted high vulnerability hotspots away from the shoreline, indicating various salinity sources. The validation of the modified method showed that nearly 80% of the sampling points present very good to perfect match between the salinity assessment and the concentration of Cl<sup>−</sup>, indicating the successful validation of the method. Overall, the GALDIT-I method facilitated groundwater vulnerability assessment to salinization more accurately and exhibited a more discrete spatial assessment, thus, it could be regarded as a promising proactive tool for groundwater management and decision-making.https://www.mdpi.com/2073-4441/14/22/3689coastal aquifergroundwater salinizationGALDITvulnerabilityRhodope |
| spellingShingle | Despina Chronidou Evangelos Tziritis Andreas Panagopoulos Efstathios K. Oikonomou Athanasios Loukas A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece) Water coastal aquifer groundwater salinization GALDIT vulnerability Rhodope |
| title | A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece) |
| title_full | A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece) |
| title_fullStr | A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece) |
| title_full_unstemmed | A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece) |
| title_short | A Modified GALDIT Method to Assess Groundwater Vulnerability to Salinization—Application to Rhodope Coastal Aquifer (North Greece) |
| title_sort | modified galdit method to assess groundwater vulnerability to salinization application to rhodope coastal aquifer north greece |
| topic | coastal aquifer groundwater salinization GALDIT vulnerability Rhodope |
| url | https://www.mdpi.com/2073-4441/14/22/3689 |
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