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The purpose of the study was to determine quantitative and qualitative changes in the waters of Lake Jamno in northern Poland due to the presence of new hydrotechnical structures in its drainage basin, with a special focus on the effects of a new storm barrier. The study consisted primarily of a review of measurement data, historical records and fieldwork prior to the construction (2002–2008) and following the construction of the storm barrier (2015). Fieldwork included hydrographic surveys and water sampling for laboratory analysis. The main and most easily discernible effect of the construction is the change in water quality in Lake Jamno. This is particularly true in the case of key indicators related to seawater, including conductivity, whose values changed from brackish to fresh water. [ABSTRACT FROM AUTHOR]

A growing concern exists about the effects of chloride (Cl) on freshwater systems. Increasing Cl concentrations have been observed in the last few decades in several rivers and lakes, mainly in northern countries. In Italy, present levels and temporal changes of sodium (Na) and Cl in water bodies have rarely been assessed. Based on long-term data for the lakes of the subalpine district in Italy (Maggiore, Lugano, Como, Iseo, Garda), we analyzed trends affecting Cl and Na concentrations during the last 25 years, with the aim of identifying temporal changes and assessing possible causes. An in-depth analysis is presented for Lake Maggiore. Positive temporal Na and Cl trends were evident in all studied lakes, with the trends increasing since early 2000s. Data for Lake Maggiore tributaries showed a clear seasonality (higher values in winter and early spring). The NaCl used as road de-icing agent, together with Cl discharge from wastewater treatment plants, were identified as the main causes for the observed trends. Chloride concentrations in the lakes are below the threshold limit for reduced water quality and below concentrations known to harm aquatic biota. However, considering the relevance of deep subalpine lakes, representing almost 80 % of the total freshwater volume in Italy, these trends indicate an important chemical change, which warrants further analysis. [ABSTRACT FROM AUTHOR]

The macroelement (HCO, SO, Cl, Ca, Mg, Na + K, as well as NO, NO, and PO) and microelement (As, Cd, Cr, Cu, Co, Fe, Mn, Ni, Pb, Zn, and V) composition of natural waters in different physiographical provinces of the Altai have been studied and characterized. It has been found that the concentrations of dissolved forms of metals in the waters of the examined rivers generally do not exceed the MAC, though in some cases, they exceed the world averages and depend on the features of water nourishment of rivers and the concentrations of mineral salts in water. A considerable portion of metals in Altai surface waters has been found to be transported as a component of suspension, though the specific concentration of metals in suspension decreases with increasing water turbidity. The effect of the structure and properties of the soil cover on the drainage basins of various physiographic provinces of the Altai on surface water chemistry is most distinct in the case of macrocomponents and typomorphic elements (Fe, Mn, Ca), as well as under anthropogenic impact on the watershed. [ABSTRACT FROM AUTHOR]

The objective of the investigation was to analyze the hydro-chemical characteristics of the underground water streams from the northern area of the province of Granma for irrigation use in agriculture. Based on the database available at the National Institute of Hydraulic Resources consisting of 303 wells, it was possible to generate through the Surfer program (version 9.0) hydro-chemical maps on scale of 1:250 000. The maps represent the mineralization, the chloride content, the water chemical class, irrigation coefficient and the marine salinity index. An integral analysis of these maps allowed zoning the hydro-chemical quality of the underground water. The analysis indicates the water streams from the southeast to the area under investigation to be of a higher quality for irrigation purposes. [ABSTRACT FROM AUTHOR]

Groundwater of Chapai Nawabganj town has been studied using hydrogeological, hydrochemical and environmental isotope (δ18O, δ²H, δ13C, ³H and 14C) data. Aquifer underneath the study area is divided into unconfined to semi-confined Holocene alluvial floodplain aquifer and confined Plio-Pleistocene Dupi Tila sandstone aquifer. Chemical composition of groundwater is characterized by high concentrations of Mg2+, Na+, Ca2+, HCO3-, FeTotal, and low concentrations of Mn2+, NO3- and PO43-. Groundwater samples are mainly Mg-Ca-HCO3 and Na-Mg-Ca-HCO3 types and Na-Mg-Ca-Cl-HCO3 type of water is also found at some places. Based on Cl- and SO42- concentrations groundwater is normal chloride and normal sulphate water, respectively. In terms of SAR and EC values water is excellent for irrigation purpose. The isotopic composition also suggests some segregation of groundwater from the different aquifers and indicates different ages of recharge. [ABSTRACT FROM AUTHOR]

Abstract: Water resources in the Middle East, particularly in Palestine, are extremely scarce and costly. The Jordan Valley is a fertile productive region, described as the food basket of Palestine. Groundwater originating from the Quaternary Aquifer System forms the main water resource in the Jordan Valley. However, the quality of this groundwater is threatened mainly by the high chloride concentration. The most representative area of the Jordan Valley is Jericho area, which was chosen to be the study area. The study area (65km2) is almost a flat area with a gentle decline towards the east. It is the lowest land on earth with ground levels reaching 400meters below sea level (mbsl) near the Dead Sea shores. The Quaternary Aquifer System in the study area could be divided into an upper alluvial layer with thickness varying from 40 to 150m and a lower low-permeable Lisan layer, which crops out in the eastern part of the study area with thickness over 200m. Hydrogeochemical investigation reveals that the water is generally earth alkaline with higher content of earth alkalis and prevailing chloride. According to Stuyfzand (1986) and Piper’s (1944) classification systems, water type in the Alluvial Aquifer varies from fresh hard CaMgHCO3 or MgCaHCO3 water in the west and northwest to brackish very-hard MgNaCl or NaMgCl in the middle. In the east, the water becomes brackish-salt extremely-hard MgNaCl or NaCl. Groundwater quality is deteriorating (increase in salinity) spatially towards the east and vertically with increasing depth (when nearing the Lisan Formation). As an indication of groundwater salinity, total dissolved solids show some variability with time over the last 21years (1983–2004). In short-time scale, there are high seasonal and yearly fluctuations with regard to salinity, specifically in Cl− and contents. Spring water from the Upper Cenomanian Aquifer (CaHCO3) represents the fresh end member, while Rift Valley Brines (RVB-CaNaCl) and Dead Sea Brines (DSB-MgNaCl) represent the saline end members. Existing water types are mixtures of the 3 end members. There is a consistency in results and analysis of geological, hydrogeological, hydrochemical and geophysical data. There are three probable sources of increase in groundwater salinity: mixing with saline end members (RVB/DSB); dissolution of minerals of the Lisan Formation (calcite, dolomite, gypsum and halite); and to some extent, agricultural effluent pollution. [Copyright &y& Elsevier]

To better understand the effects of recharge and discharge on the hydrogeochemistry of high levels of arsenic (As) and fluoride (F) in groundwater, environmental isotopic composition (&delta²H and &delta18O) and chloride (CI) concentrations were analyzed in 29 groundwater samples collected from the Datong Basin. High arsenic groundwater samples (As > 50 μg/L) were found to be enriched in lighter isotopic composition that ranged from --92 to --78 ∞ for deuterium (&delta²H) and from -12.5 to -9.9 ∞ for oxygen-18 (&delta18O). High F-containing groundwater (F > 1 mg/L) was relatively enriched in heavier isotopic composition and varied from --90 to -57 ∞ and from -12.2 to -6.7 ∞ for &delta²H and &delta18O, respectively. High chloride concentrations and &delta18O values were primarily measured in groundwater samples from the northern and southwestern portions of the study area, indicating the effect of evaporation on groundwater. The observation of relatively homogenized and low &delta18O values and chloride concentrations in groundwater samples from central part of the Datong Basin might be a result of fast recharge by irrigation returns, which suggests that irrigation using arsenic-contaminated groundwater affected the occurrence of high arsenic-containing groundwater in the basin. [ABSTRACT FROM AUTHOR]

Abstract: Water treatment processes can cause secondary changes in water chemistry that alter finished water quality including chloride, sulfate, natural organic matter (NOM), and metal release. Hence, the goal of this research was to provide an improved understanding of the chloride-to-sulfate mass ratio (CSMR) with regards to chloride and sulfate variations at full-scale water treatment plants and corrosion potential under simulated premise plumbing conditions. Laboratory corrosion studies were conducted using Pb–Sn solder/Cu tubing galvanic cells exposed to model waters with low (approx. 5 mg/L Cl− and 10 mg/L SO4 2–) and high (approx. 50 mg/L Cl− and 100 mg/L SO4 2–) concentrations of chloride and sulfate at a constant CSMR of ∼0.5. The role of NOM during corrosion was also evaluated by changing the type of organic material. In addition, full-scale sampling was conducted to quantify the raw water variability of chloride, sulfate, and NOM concentrations and the changes to these parameters from magnetic ion exchange treatment. Test conditions with higher concentrations of chloride and sulfate released significantly more lead than the lower chloride and sulfate test waters. In addition, the source of NOM was a key factor in the amount of lead released with the model organic compounds yielding significantly less lead release than aquatic NOM. [Copyright &y& Elsevier]

The common Lewis acid AlCl3 has efficiently produced 5-hydroxymethylfurfural (HMF) from carbohydrate and biopolymer substrates in water, DMSO, and water–methylisobutylketone biphasic solvents under microwave irradiation. The yield of HMF in different solvents follows an increasing order from water to water–MIBK biphasic solvent to DMSO. The yield of HMF increased with an increase in catalyst loading whereas it remains unchanged upon increase of the carbohydrate concentration. In most reactions, the maximum yield of HMF is recorded within 2 min of reaction time. The mechanism of the AlCl3 catalyzed glucose dehydration reaction is proposed to proceed through the isomerization of glucopyranose to fructofuranose, followed by a proton assisted transformation of fructofuranose to HMF. [ABSTRACT FROM AUTHOR]