Variations In Water Composition Research Articles

Freshwater fish otoliths record signals from both water and physiological processes: new insights from Sr/Ca and Ba/Ca ratios

Using strontium (Sr) and barium (Ba) in otoliths to determine natal origins and understand patterns of fish movements is based on the fundamental assumption that otoliths record water chemistry signals without any major alterations. Although prior studies highlighted that fish physiology can modify the water signal in otoliths, studies for freshwater fish are scarce. We exposed different groups of Atlantic salmon parr Salmo salar to different scenarios of ambient-level variations in Sr/Ca and Ba/Ca ratios and then combined otolith chemical profiles with environmental data (water chemistry and temperature), Fulton's index, and otolith growth rates to assess what factors explain/influence the elemental ratios of Sr and Ba in otoliths. Generalized additive mixed models (GAMMs) using water-based otolith composition, temperature, Fulton's index, and “individual” as explanatory variables allow to demonstrate that water chemistry alone cannot fully explain measured ratios in otoliths, except in scenarios involving significant changes in water chemistry. Other factors (physiological effects) should be accounted for reproducing short and minimal seasonal variations in water composition, considering that inter-individual variability contributes quite significantly in most scenarios.

Spatio-temporal variation of nitrate based on Landsat 8 in Playa Colorada bay, Sinaloa, Mexico.

Characterizing water quality in coastal waters through spatial observations is challenging, due to spatial and temporal variations in water composition. Nitrate, an important compound for water quality assessment, has received little attention in estimates made from satellite measurements, even though it can be estimated using models generated from multispectral images. Since nitrate is a non-optically active parameter that can be correlated with optically active parameters, it was related to bands of the visible and infrared spectrum, captured in Landsat-8 images, and used to generate empirical models to estimate the spatio-temporal variation of nitrate concentration in the Playa Colorada Bay, in the state of Sinaloa Northwest Mexico. Four sampling campaigns were performed, two in spring and two in fall. Nitrate nitrogen (NO3-N) concentration ranged between 0.69 and 1.80mg/L, values higher than those recommended in the Mexican ecological criteria of water quality for the protection of marine aquatic life in coastal areas. Generated models showed a significant relationship (P < 0.05) between NO3-N and band reflectance in the infrared (band 5) and short-wave infrared (band 6 and band 7) spectra of Landsat-8 imagery. The B6 band appeared in all models selected to estimate NO3-N in the bay. These results evidence the potential of Landsat-8 images for the estimation of nitrate in the coastal waters of Sinaloa, México.

Inclusion of seasonal variation in river system microbial communities and phototroph activity increases environmental relevance of laboratory chemical persistence tests

Regulatory tests assess crop protection product environmental fate and toxicity before approval for commercial use. Although globally applied laboratory tests can assess biodegradation, they lack environmental complexity. Microbial communities are subject to temporal and spatial variation, but there is little consideration of these microbial dynamics in the laboratory. Here, we investigated seasonal variation in the microbial composition of water and sediment from a UK river across a two-year time course and determined its effect on the outcome of water-sediment (OECD 308) and water-only (OECD 309) biodegradation tests, using the fungicide isopyrazam. These OECD tests are performed under dark conditions, so test systems incubated under non-UV light:dark cycles were also included to determine the impact on both inoculum characteristics and biodegradation. Isopyrazam degradation was faster when incubated under non-UV light at all collection times in water-sediment microcosms, suggesting that phototrophic communities can metabolise isopyrazam throughout the year. Degradation rate varied seasonally between inoculum collection times only in microcosms incubated in the light, but isopyrazam mineralisation to 14CO2 varied seasonally under both light and dark conditions, suggesting that heterotrophic communities may also play a role in degradation. Bacterial and phototroph communities varied across time, but there was no clear link between water or sediment microbial composition and variation in degradation rate. During the test period, inoculum microbial community composition changed, particularly in non-UV light incubated microcosms. Overall, we show that regulatory test outcome is not influenced by temporal variation in microbial community structure; however, biodegradation rates from higher tier studies with improved environmental realism, e.g. through addition of non-UV light, may be more variable. These data suggest that standardised OECD tests can provide a conservative estimate of pesticide persistence end points and that additional tests including non-UV light could help bridge the gap between standard tests and field studies.

Geothermal and Mineralogic Analysis of Hot Springs in the Puracé-La Mina Sector in Cauca, Colombia

Thermal waters are natural resources of great value to geothermal sciences, the tourism industry, and health. In this work, geochemical classification of physicochemical results of 17 sources at the Puracé-La Mina (Cauca, Colombia) sector was implemented in order to strengthen and determine their potential applications and enhance the continental tourism in Colombia. The analyzed parameters were developed following the Standard Methods 22nd edition, at Universidad Nacional de Colombia-Manizales. According to the results obtained by means of a geochemical classification, it was found that most of the sources have a sulfated-acid nature which makes them heated vapor waters and volcanic waters. Likewise, it was observed that all the sources are immature waters and still do not reach chemical equilibrium. On the other hand, mineralogical and chemical characterization by means of XRD and XRF showed a high content of silica isomorphous minerals with a low concentration. In addition, the presence of Fe2O3 was observed, which is insoluble at pH &gt; 5 and remains in the rock. Nevertheless, considering that mine sources possess pH ± 2 and temperatures of 40°C, leaching is possible for iron justifying its presence in the water. Instead, elements like Na+, K+, Mg2+, and Ca2+ have high mobility at the conditions of mine sources (low pH) as a consequence of hydrolysis processes, which produce variations in water composition.

Persistence of immersed blood and hair DNA: A preliminary study based on casework

In some cases, evidence is collected from rivers, canals, lakes or sink pipes. To determine the utility of analyzing these samples and for cases in which DNA was recovered from submerged bulletproof vest parts, we evaluated the time necessary to degrade the blood and, subsequently, DNA on bulletproof vests. In a second experiment, also based on cases, blood was diluted in water from a kitchen sink pipe and incubated at room temperature for different times. Subsequently, DNA quality was assessed. In a parallel experiment, hair roots were incubated in spring water for different time periods.This study demonstrates that after one week of immersion of the bulletproof vest parts in a canal only one sample from more than 100 samples gave a partial genetic profile. No genetic profile were obtained for the 99 other samples. After one month immersion and despite the finding that blood remained detectable on bulletproof vest parts, no genetic profile was obtained for all samples using the classical STR approach. For longer immersion times, no genetic profiles were obtained.In sink pipe water, an incubation time of 72 h (h) was necessary before significant blood degradation occurred. Nevertheless, high inter-sample variability was observed. This high variability may be explained by the variability of water composition coming from nine different sink pipes.For hair root cells incubated in water, we observed that more than 90% of the DNA was degraded after 72 h.

Экологическое состояние реки Урал

The article describes the ecological state of the Ural River at the present stage. Hydrochemical regime of the reservoir is an important indicator to regulating the number of water resources. As the Ural River is the transboundary reservoir, it is prone to contamination from various areas in the upper and middle reaches. Monitoring of the ecological state of the Ural River showed the presence of anthropogenic pollution. The hydrochemical regime of the reservoir is subject to changes in seasonal variations in water composition. In spring, with flood waters, the main pollution enters the river, however in other seasons, the quality of water leaves much to be desired. In autumn, in comparison with the spring, both alkalinity and salinity increased. The reservoir is prone to contamination with nitrites in almost all seasons of the year from 0.05 to 0.20 mg/dm3 (December, 2016). In the lower reaches of the Ural River, the content of readily oxidizable organic compounds ranges from 3.2 mg/dm3 (winter) to 7.36 mg/dm3 (autumn). The content of boron exceeds the maximum permissible concentration 1-3 times. Environmental monitoring conducted in different periods of the year showed a constant source of pollution flow into the reservoir, which was increased in the flood period. Concentrations of nitrite, boron and petroleum products in the Ural River exceed their permitted values at the point in the end of Uralsk city. The results of the research confirm that the source of the contamination of Ural River is its confluent Ilek River originating from Aktobe Oblast.

Controls on surface water quality in the River Clyde catchment, Scotland, UK, with particular reference to chromium and lead

ABSTRACTThree collated geochemical surveys of surface water in the Clyde catchment have established the spatial variability in water composition, primarily under baseflow conditions. The waters are broadly pH-neutral to alkaline (maximum pH 8.7) in the lowlands, but mildly acidic in uplands on the catchment periphery. Electrical conductance is relatively high in lowland streams (maximum 8320μgL–1), with lower values in the uplands. Dissolved chromium (Cr; &lt;0.05–971μgL–1) and lead (Pb; &lt;0.05–19.4μgL–1) are of importance due to recognised pollution sources within the catchment. High aqueous Cr concentrations (&gt;5μgL–1) are recorded in urban areas associated with the disposal of alkaline industrial chromite ore processing residue. Under such conditions, Cr probably occurs as Cr(VI). Numerous relatively high Pb values occur in the upland and urban areas. These are likely to be associated with a combination of soil reactions, diffuse pollution and contamination from Pb mineralisation/mining. Pb has a stronger correlation with water pH than with stream sediment Pb content, suggesting that pH has a greater control on Pb mobility than host-rock Pb. Exceedances of water-quality standards are &lt;1% for both Cr and Pb across the catchment. Absolute exceedances are more extreme for Cr than for Pb, highlighting the scale of the Cr pollution problem for urban surface water within the catchment.

Accurate experimental determination of the isotope effects on the triple point temperature of water. I. Dependence on the 2H abundance

Variation in the isotopic composition of water is one of the major contributors to uncertainty in the realization of the triple point of water (TPW). Although the dependence of the TPW on the isotopic composition of the water has been known for years, there is still a lack of a detailed and accurate experimental determination of the values for the correction constants. This paper is the first of two articles (Part I and Part II) that address quantification of isotope abundance effects on the triple point temperature of water. In this paper, we describe our experimental assessment of the 2H isotope effect. We manufactured five triple point cells with prepared water mixtures with a range of 2H isotopic abundances encompassing widely the natural abundance range, while the 18O and 17O isotopic abundance were kept approximately constant and the 18O − 17O ratio was close to the Meijer–Li relationship for natural waters. The selected range of 2H isotopic abundances led to cells that realised TPW temperatures between approximately −140 μK to +2500 μK with respect to the TPW temperature as realized by VSMOW (Vienna Standard Mean Ocean Water). Our experiment led to determination of the value for the δ2H correction parameter of A2H = 673 μK / (‰ deviation of δ2H from VSMOW) with a combined uncertainty of 4 μK (k = 1, or 1σ).

Spatial variation of the chemical composition of lake waters in the Tatra National Park

Abstract The aim of this study is to determine the factors affecting the spatial variation of the chemical composition of lake waters in the Tatra Mountains. In most cases, the lake waters are acidic and very dilute, with a low ionic content and low conductivity values. In general, HCO3 - is the predominant anion and Ca2+ is the predominant cation in the chemical composition of the analysed water samples. Among nutrients, NO3 - is the dominant form of nitrogen, but also NH4 + may be found in lake waters. By using principal component analysis (PCA) two factors have been identified that explain 63.6% of the variation in the chemical composition of water. Factor 1, which explains 43.2% of the total variability, is associated with Ca2+, SO4 2-, HCO3 -, Na+, pH and lake area and is related to weathering and atmospheric deposition. Factor 2 explains 20.4% of the total variability and is associated with Mg2+, K+, Cl- and with lake altitude. In terms of chemical composition, based on the projection of cases of the first and second factor, the lakes in the Tatra Mountains may be divided into four groups, representing the following: lakes situated within the subalpine forest at the lowest altitude (&lt;1300 m a.s.l.), characterized by medium mineralization (~14 mg dm-3) and the highest concentration of NH4 + and Cl- (Group I, 8 lakes); slightly alkaline lakes, with the lowest average acidification, medium mineralization (~31 mg dm-3) and the highest concentrations of Ca2+, Mg2+, Na+, K+, HCO3 -, SO4 2-, and low concentrations of NO3 - (Group II, 2 lakes); small lakes (&lt;0.01 ha) located within the alpine meadow and the nival zones at high elevations with the lowest mean mineralization (~4.3 mg dm-3), with the highest ammonium contribution to the sum of ions among all lakes and the largest sensitivity to acidification (Group III, 13 lakes); large lakes with high mineralization and slightly acidic pH (Group IV, 26 lakes) and medium mineralization (~31 mg dm-3).

Trends in water quality variability for coalbed methane produced water

Energy production from unconventional natural gas resources, such as coalbed methane, has the potential to generate significant water quantities for use in water-stressed areas to augment existing water supplies. Coalbed methane (CBM) produced water is generated from shallower formations than traditional oil and gas resources where water quality may be influenced by fresh water supplies in the area. Variability in produced water quality between wells and across geologic basins must be characterized in order to categorize water types appropriate for beneficial use. Principal component analysis (PCA) was applied to a composite geochemical database to identify indicators of variability in water composition and quality. Component analysis revealed that water quality indicators of variability were related to: (i) aquifer recharge that dilutes constituent concentrations (37%), (ii) dissolution of soluble aquifer minerals such as sodium and exchange of calcium and magnesium (13.8%), and (iii) coal depositional environment influence on chloride and trace metal fractions (14% of variability). Ternary relationships between Na–Cl–HCO3 and Na–Ca–Mg correlate to marine influence in the coal depositional environment and well proximity to recharge, respectively. Relationships identified in this study highlight water quality compositions with opportunities for beneficial use.

Impact of tecnogenic halogenesis on water catchment landscapes of river valleys and water systems: Case study of the south of Tyumen province

The article gives the analysis of the impact of artesian mineralized water flowing from old prospecting wells on water catchment landscapes of river valleys and small watercourses. The processes related to the variation in ion composition of water and chemical composition of bottom sediments of small watercourses under the impact of the technogenic halogenesis are discussed.

Radioelement Solubilities in SR-Site, the Influence of Variability and Uncertainty

ABSTRACTIf groundwater enters a damaged canister and comes in contact with the spent fuel, radionuclides are released into the water in the void inside the canister when fuel dissolves. Solubility limits restrict the amount of radioelements that may migrate with the water flowing from the canister. In this study the impact of variability in groundwater chemistry compositions and the impact of uncertainties in thermodynamic data on solubility limits for Np, Pb, Pu, Ra, Se, Th, U and Zr were looked into. The solubility limits for all the studied radioelements seemed to be more sensitive to uncertainties in thermodynamic data than to differences in groundwater chemistry. The sole exception was radium, where variability in water composition has a somewhat larger impact. Radium is also the most safety critical element in the safety assessment SR-Site and groundwater compositions are expected to vary during the assessment period of one million years.

Fine scale variations of surface water chemistry in an ephemeral to perennial drainage network

AbstractAlthough temporal variation in headwater stream chemistry has long been used to document baseline conditions and response to environmental drivers, less attention is paid to fine scale spatial variations that could yield clues to processes controlling stream water sources. We documented spatial and temporal variation in water composition in a headwater catchment (41 ha) at the Hubbard Brook Experimental Forest, NH, USA. We sampled every 50 m along an ephemeral to perennial stream network as well as groundwater from seeps and 35 shallow wells across varying flow conditions. Groundwater influences on surface water in this region have not been considered to be important in past studies as relatively coarse soils were assumed to be well drained in steep catchments with flashy runoff response. However, seeps displayed perennial discharge, upslope accumulated areas (UAA) smaller than those for channel initiation sites and higher pH, Ca and Si concentrations than streams, suggesting relatively long groundwater residence time or long subsurface flow paths not bound by topographic divides. Coupled with a large range in groundwater chemistry seen in wells, these results suggest stream chemistry variation reflects the range of connectivity with, and quality of, groundwater controlled by hillslope hydropedological processes. The magnitude of variations of solute concentrations seen in the first order catchment was as broad as that seen at the fifth order Hubbard Brook Valley (3519 ha). Reduction in variation in solute concentrations with increasing UAA suggested a representative elementary area (REA) value of less than 3 ha in the first order catchment, compared with 100 ha for the fifth order basin. Thus, the REA is not necessarily an elementary catchment property. Rather, the partitioning of variation between highly variable upstream sources and relatively homogenous downstream characteristics may have different physical significance depending on the scale and complexity of the catchment under examination. Copyright © 2012 John Wiley &amp; Sons, Ltd.

Formation of the composition and quality of carbonate mineral water of the Elburgan water bearing complex (Essentuki Town)

The problems of underground water formation in the Elburgan water bearing stratum in conditions close to a marine sedimentation basin are considered in this article. As well, we consider variations in water composition under the influence of mixing with ground waters during water pumping for commercial purposes, and the deterioration of water quality caused by a decrease in the mineralization of mixture, considered with respect to the degree of mineralization accepted for waters used for medical purposes.

Spatial variations in water composition at a northern Canadian lake impacted by mine drainage

Release of acid drainage from mine-waste disposal areas is a problem of international scale. Contaminated surface water, derived from mine wastes, orginates both as direct surface runoff and, indirectly, as subsurface groundwater flow. At Camp Lake, a small Canadian Shield lake that is in northern Manitoba and is ice-covered 6 months of the year, direct and indirect release of drainage from an adjacent sulfide-rich tailings impoundment has severely affected the quality of the lake water. Concentrations of the products from sulfide oxidation are extremely high in the pore waters of the tailings impoundment. Groundwater and surface water derived from the impoundment discharge into a semi-isolated shallow bay in Camp Lake. The incorporation of this aqueous effluent has altered the composition of the lake water, which in turn has modified the physical limnology of the lake. Geochemical profiles of the water column indicate that, despite its shallow depth (6 m), the bay is stratified throughout the year. The greatest accumulation of dissolved metals and SO 4 is in the lower portion of the water column, with concentrations up to 8500 mg L −1 Fe, 20,000 mg L −1 SO 4, 30 mg L −1 Zn, 100 mg L −1 Al, and elevated concentrations of Cu, Cd, Pb and Ni. Meromictic conditions and very high solute concentrations are limited to the bay. Outside the bay, solute concentrations are lower and some stratification of the water column exists. Identification of locations and composition of groundwater discharge relative to lake bathymetry is a fundamental aspect of understanding chemical evolution and physical stability of mine-impacted lakes.

Action of pulsed low frequency electromagnetic fields on physicochemical properties of water: incidence on its biological activity

The electromagnetic fields (EMF) effects on water is presently controversial mainly because of variation in water composition and/or environmental conditions. In the present study, we developed new experimental procedures in order to investigate the physicochemical as well as the biological effects of EMF on water. We studied the action of pulsed low frequency electromagnetic fields on the physicochemical properties of water samples prepared under severely controlled conditions. The effect was characterised by using elastic light scattering and photoluminescence: intensities decreased by 25 and 70 % respectively. Our interpretation is (1) that low frequency electromagnetic fields act on the gas/water interface by disturbing the ionic double-layer which stabilises the gas nanobubbles in water (2) that photoluminescence results from the excitation of these hydrated ionic compounds. These results open interesting perspectives in biology. We present preliminary results of germination experiments.

Seasonal variation in oxygen isotope composition of waters for a montane larch forest in Mongolia

Measurements of water oxygen isotopic composition were conducted in the 2003 growing season for a montane larch (Larix sibirica Ledeb.) forest in northern Mongolia, a transitional area from the south Siberian taiga to the Asian steppe. Oxygen isotopic composition of foliar water and its daily variability were found to be sensitive to atmospheric evaporative demand. During most of the growing season, water sources used by larch trees were from the upper 30-cm surface layer of the soil when precipitation input was large, and were from the deeper layer when the water supply at the upper soil layer was limited. The Keeling plot method suggested that the forest returned soil water to the atmosphere predominantly by means of canopy transpiration during the peak growth period (in August).

Hydrophobicity and reactivity of trace metals in the low‐salinity zone of a turbid estuary

We chemically fractionated water samples from the low‐salinity zone of a turbid estuary (Tamar, UK) using C18 columns to examine the controls on the complexation, hydrophobicity, and reactivity of dissolved trace metals (Co, Cu, Mn, and Pb). The hydrophobic (C18‐retained) fraction of metal was related to the solubility of metal in the amphiphilic solvent, n‐octanol, and in acid‐base titrations and for all metals this fraction exhibited a peak centered around pH 7–8 in both freshwater and brackish water. In freshwater, hydrophobicity decreased in the order Pb &gt; Cu &gt; Mn &gt; Co, and in brackish water, hydrophobicity was either reduced (Cu and Pb) or enhanced (Co and Mn) compared to freshwater, but in all cases peaks were more distinct. Salinity distributions of dissolved trace metals in the estuary indicated significant removal of Co, Cu, and Mn, and a source of Pb that was coincident with the onset of the turbidity maximum, and all distributions could be accounted for empirically by end‐member water mixing and sediment resuspension. Salinity distributions of the hydrophobic fraction of metal were not consistent with any variation in water composition (including pH), but revealed that this fraction was preferentially removed from (Co, Cu, and Mn) or added to (Pb) the aqueous phase in the vicinity of the turbidity maximum. Removal implies that hydrophobic species are more reactive than hydrophilic species, and that either re‐equilibration between these fractions is not attained within the hydrodynamic timescales of the upper estuary, or new equilibria are established by the buffering effects of additional anions and ligands in the water column. Addition of hydrophobic species of Pb coincided with minimum total and hydrophobic concentrations of Co, Cu, and Mn, and could, therefore, be explained in terms of reduced competition for nonspecific hydrophobic ligands from these and other (e.g., Al) metals in this region of the estuary.

Variability of Water Composition and Potential Impact on Animal Performance

Water is often overlooked as an important nutrient in livestock diets. Animals need a plentiful supply of good, clean water for normal rumen fermentation and metabolism, proper flow of feed through the digestive tract, nutrient absorption, maintaining normal blood volume and tissue requirements. In addition to assessing adequacy and cleanliness of waterers, as well as water supply, nutrition advisors and clinicians need to assess chemical composition of water. Despite the importance of water to livestock, limited research has examined the water composition variability and the impact on animal performance. This paper summarizes survey results of 3651 water samples collected throughout the United States of America.

Diurnal variation in the stable isotope composition of water and dry matter in fruiting Lupinus angustifolius under field conditions

AbstractIn this paper, we present an integrated account of the diurnal variation in the stable isotopes of water (δD and δ18O) and dry matter (δ15N, δ13C, and δ18O) in the long‐distance transport fluids (xylem sap and phloem sap), leaves, pod walls, and seeds of Lupinus angustifolius under field conditions in Western Australia. The δD and δ18O of leaf water showed a pronounced diurnal variation, ranging from early morning minima near 0‰ for both δD and δ18O to early afternoon maxima of 62 and 23‰, respectively. Xylem sap water showed no diurnal variation in isotopic composition and had mean values of −13·2 and −2·3‰ for δD and δ18O. Phloem sap water collected from pod tips was intermediate in isotopic composition between xylem sap and leaf water and exhibited only a moderate diurnal fluctuation. Isotopic compositions of pod wall and seed water were intermediate between those of phloem and xylem sap water. A model of average leaf water enrichment in the steady state (Craig &amp; Gordon, pp. 9–130 in Proceedings of a Conference on Stable Isotopes in Oceanographic Studies and Palaeotemperatures, Lischi and Figli, Pisa, Italy, 1965; Dongmann et al., Radiation and Environmental Biophysics 11, 41–52, 1974; Farquhar &amp; Lloyd, pp. 47–70 in Stable Isotopes and Plant Carbon–Water Relations, Academic Press, San Diego, CA, USA, 1993) agreed closely with observed leaf water enrichment in the morning and early afternoon, but poorly during the night. A modified model taking into account non‐steady‐state effects (Farquhar and Cernusak, unpublished) gave better predictions of observed leaf water enrichments over a full diurnal cycle. The δ15N, δ13C, and δ18O of dry matter varied appreciably among components. Dry matter δ15N was highest in xylem sap and lowest in leaves, whereas dry matter δ13C was lowest in leaves and highest in phloem sap and seeds, and dry matter δ18O was lowest in leaves and highest in pod walls. Phloem sap, leaf, and fruit dry matter δ18O varied diurnally, as did phloem sap dry matter δ13C. These results demonstrate the importance of considering the non‐steady‐state when modelling biological fractionation of stable isotopes in the natural environment.