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Author Wigley, T.M.L.; Plummer, L.N. doi  openurl
  Title Mixing of carbonate waters Type Journal Article
  Year 1976 Publication Geochimica et Cosmochimica Acta Abbreviated Journal  
  Volume 40 Issue 9 Pages 989-995  
  Keywords  
  Abstract When mineral solutions of different compositions are mixed, the molalities and activities of individual ions in the mixture are often non-linear functions of their end-member values. This non-linearity is particularly significant in determining mineral saturation levels. Mixtures of saturated solutions may be either undersaturated or supersaturated depending on the end-member compositions and the physical conditions in which end-members and their mixtures exist. In carbonate solutions important non-linear effects occur due to redistribution of carbonate species. In extreme cases this causes mixture pH to be below both the end-member pH values. A simple but precise computer program (WATMIX) has been developed for calculating mixture composition for closed and open system mixing of arbitrary end-members. A number of mixing examples are considered which allow one to isolate three important processes leading to non-linear behaviour: the algebraic effect, the δPCO2 effect, and the ionic strength effect.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue (up) Edition  
  ISSN 0016-7037 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Wigley1976 Serial 40  
Permanent link to this record
 

 
Author Zhou, X.; Li, C. url  openurl
  Title Hydrogeochemistry of deep formation brines in the central Sichuan Basin, China Type Journal Article
  Year 1992 Publication Journal of Hydrology Abbreviated Journal  
  Volume 138 Issue 1 Pages 1-15  
  Keywords  
  Abstract Subsurface brines are abundant in the Sichuan Basin, China. Five brine-bearing aquifers have been identified within rocks of Triassic age in the central part of the basin. These are of two types: brine-bearing clastic and brine-bearing carbonate aquifers. Brines in this region have high total dissolved solids and chemical species that are different from those of evaporatively concentrated seawater. Deep formation brines in clastic aquifers, in which evaporites do not exist, are characterized by high concentrations of Ca, Sr, Ba, Br and I, low concentrations of Mg and K, and lack of SO4, and are dominated by the NaCaCl type. Brines in carbonate aquifers, which have interbeds of evaporites, are characterized by high total dissolved solids, low concentrations of Ca, Mg and SO4, and lack of Ba, and are of the NaCl type. The brines in clastic aquifers originate from connate continental sedimentary waters mixed with marine waters; membrane filtration through shales has played an important part in modifying the chemical compositions and increasing the salinity of the brines. Those in carbonate aquifers are bittern marine sedimentary waters, with chemical compositions mainly controlled by precipitation of evaporites.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue (up) Edition  
  ISSN 0022-1694 ISBN Medium  
  Area Asia Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Zhou19921 Serial 41  
Permanent link to this record
 

 
Author Alexakis, D.; Gotsis, D.; Giakoumakis, S. url  doi
openurl 
  Title Evaluation of soil salinization in a Mediterranean site (Agoulinitsa district—West Greece) Type Journal Article
  Year 2015 Publication Arabian Journal of Geosciences Abbreviated Journal  
  Volume 8 Issue 3 Pages 1373-1383  
  Keywords Agricultural soil . Soil quality . Soil salinization  
  Abstract Soil salinization is an environmental problem having

significant impacts on the soil–water–plant system. This

problem is more frequent in coastal areas due to seawater

intrusion into the land. Assessing the soil salinization is a

critical issue for the agricultural areas situated in the

Mediterranean basin. This paper examines the deterioration

of soil quality in the cultivated land of a Mediterranean site

(Agoulinitsa district—West Greece). Soil samples were collected

in both pre-irrigation and post-irrigation seasons.

Electrical conductivity (EC), pH and the ions Br−, Ca2+, Cl−,

F−, K+, Li+, Mg2+, Na+, NH4

+, NO2

−, NO3

−, PO4

3− and SO4

2−

were determined by the 1:2 (soil/water ratio on weight basis)

method. The salts which were present in both seasons in the

soils of the area studied are KCl, MgCl2, NaCl, CaSO4 and

K2SO4. The wide spatiotemporal variation of EC in the cultivated

land in both seasons demonstrates that soil salinity is

controlled mainly by seawater intrusion and anthropogenic

factors such as the application of salt-rich water which is

directly pumped from the drainage ditches. Seawater intrusion

provides the affected soil with elevated contents of Ca2+, Cl−,

K+, Mg2+, Na+ and SO4

2−. Classification of the soils by using

criteria given by the literature is discussed. Practices to prevent,

or at least ameliorate, salinization in the cultivated land

of Agoulinitsa district are proposed.
 
  Address  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue (up) Edition  
  ISSN 1866-7511 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ luqianxue.zhang @ Alexakis2015 Serial 42  
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Author Di Lorenzo, T.; Galassi, D.M.P. url  doi
openurl 
  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.
 
  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 (up) 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 El Mandour, A.; El Yaouti, F.; Fakir, Y.; Zarhloule, Y.; Benavente, J. url  doi
openurl 
  Title Evolution of groundwater salinity in the unconfined aquifer of Bou-Areg, Northeastern Mediterranean coast, Morocco Type Journal Article
  Year 2007 Publication Environmental Geology Abbreviated Journal  
  Volume 54 Issue 3 Pages 491-503  
  Keywords Unconfined aquifer, Groundwater salinity, Seawater intrusion, Nitrate pollution, Lagoon, Morocco  Bou-Areg  
  Abstract The Bou-Areg plain in the Mediterranean coast at the North-eastern of Morocco is characterized by a semiarid climate. The aquifer consists of two sedimentary formations of Plio-quaternary age: the upper formation of fine silts and the lower one of coarse silts with sand and gravels. The aquifer is underlain by marly bedrock of Miocene age that dips toward the coastal lagoon of Bou-Areg. The

hydrodynamic characteristics vary between 10–4 and 10–3 m/s; and transmissivities range between 10–4 and 10–1 m2 /s. The general direction of flow is SW to NE, toward the lagoon. The aquifer is crossed by the river Selouane, which also ends in the lagoon. The groundwater is characterized by a high salinity that can reach 7.5 g/l. The highest values are observed in the upstream and in the downstream sectors of the aquifer. The temporal evolution of the physicochemical parameters depends on the climatic conditions and

piezometric variations. The analysis of the spatio-temporal distribution of the physico-chemical parameters suggests different sources of groundwater salinization: the seawater intrusion, the influence of marly gypsum-bearing terrains, and the influence of anthropogenic products as the agricultural fertilizers, which cause great nitrate concentrations that vary between 80 and 140 mg/l.
 
  Address  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue (up) Edition  
  ISSN 0943-0105 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ luqianxue.zhang @ ElMandour2008 Serial 44  
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