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| Author | Di Lorenzo, T.; Galassi, D.M.P. | ||||
| Title | Agricultural impact on Mediterranean alluvial aquifers: do groundwater communities respond? | Type | Journal Article | ||
| Year | 2013 | Publication | Fundamental and Applied Limnology/Archiv für Hydrobiologie | Abbreviated Journal | |
| Volume | 182 | Issue  |
4 | Pages | 271-282 |
| Keywords | alluvial aquifers, groundwater, stygobiont, nitrate, overexploitation | ||||
| Abstract | In Mediterranean countries agricultural development heavily depends on groundwater availability due to arid and semi-arid climate and poor surface-water resources. Agriculture represents one of the most relevant pressures which generate impacts in alluvial aquifers by means of fertilizers and pesticides usage and groundwater overexploitation. Until now, very few studies have addressed the ecological response of groundwater fauna to groundwater contamination and overexploitation due to agricultural practices. We investigated a Mediterranean alluvial aquifer heavily affected by nitrates contamination and groundwater abstraction stress due to crop irrigation. The aim of this study was to evaluate the sensitivity of groundwater communities to (a) groundwater nitrate contamination, (b) groundwater abstraction due to irrigation practices, and (c) saltwater intrusion. The present work suggests that nitrate concentration lower than 150 mg l –1 is not an immediate threat to groundwater biodiversity in alluvial aquifers. This conclusion must be carefully considered in the light of the total lack of knowledge of the effects of long-term nitrate pollution on the groundwater biota. Moreover, local extinctions of less tolerant species, prior to monitoring, cannot be ruled out. Conversely, species abundances in ground water are affected by groundwater withdrawal, but species richness may be less sensitive. This result is attributable to the disappearance of saturated microhabitats and to the depletion of fine unconsolidated sediments, reducing the surface available to bacterial biofilm, which represent the trophic resource for several groundwater invertebrates and where the main aquifer self-purification processes, such as denitrification, take place. Saltwater intrusion seems not to affect groundwater species at the values measured in this coastal aquifer. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | E. Schweizerbart'sche Verlagsbuchhandlung | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1863-9135 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | THL @ luqianxue.zhang @ DiLorenzo2013 | Serial | 43 | ||
| Permanent link to this record | |||||
| Author | Qi, H.; Ma, C.; He, Z.; Hu, X.; Gao, L. | ||||
| Title | Lithium and its isotopes as tracers of groundwater salinization: A study in the southern coastal plain of Laizhou Bay, China | Type | Journal Article | ||
| Year | 2019 | Publication | The Science of the Total Environment | Abbreviated Journal | Sci Total Environ |
| Volume | 650 | Issue |
Pt 1 | Pages | 878-890 |
| Keywords | Brine and seawater intrusion; Groundwater salinization; Hydrochemistry; Lithium isotope; Southern coastal plain of Laizhou Bay | ||||
| Abstract | In the southern coastal plain of Laizhou Bay, due to intensive exploitation of groundwater since the early 1970s, the shallow aquifer has been severely influenced by saltwater intrusion, which causes the extraction to shift from shallow to deeper aquifer changing the hydrogeological condition greatly. This study was conducted to investigate the groundwater salinization using hydrochemistry and H, O and Li isotope data. Dissolved Li shows a linear correlation with Cl and Br in seawater, brine and saline groundwater indicating the marine Li source, whereas the enrichment of Li in surface water, brackish and fresh groundwater is impacted by dissolution of silicate minerals. The analyses of hydrochemistry and isotopes (H, O and Li) indicate that brine originated from seawater evaporation, followed by mixing processes and some water-rock interactions; shallow saline groundwater originated from brine diluted with seawater and fresh groundwater; deep saline groundwater originated from seawater intrusion. The negative correlation of δ(7)Li and Li/Na in surface water, brackish and fresh groundwater is contrary to the general conclusion, indicating the slow weathering of silicate minerals and hydraulic interaction between surface water and shallow groundwater in this area. The analyses of hydrochemistry and isotopes (Li, H and O) can well identify the salinity sources and isotope fractionation in groundwater flow and mixing, especially groundwater with high TDS. As both mixing with saltwater and isotope fractionation can explain the combination of high δ(7)Li and low TDS in brackish groundwater, isotope fractionation may limit their use in recognizing salinity sources of groundwater with low TDS. | ||||
| Address | School of Environmental Studies, China University of Geosciences, Wuhan 430074, China | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0048-9697 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:30308862 | Approved | no | ||
| Call Number | THL @ christoph.kuells @ | Serial | 184 | ||
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