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1.
Quality of groundwater in the Yarmouk basin, Jordan has been assessed through the study of hydrogeochemical characteristics and the water chemistry as it is considered the main source for drinking and agriculture activities in the region. The results of the relationship between Ca2+ + Mg2+ versus HCO3? + CO32?, Ca2+ + Mg2+ versus total cations, Na+ + K+ versus total cations, Cl? + SO42? versus Na+ + K+, Na+ versus Cl?, Na+ versus HCO3? + CO32?, Na+ versus Ca2+, and Na+: Cl? versus EC describe the mineral dissolution mechanism through the strong relationship between water with rocks in alkaline conditions with the release of Ca2+, Mg2+, Na+, K+, HCO3?, CO32?, SO42?, and F? ions in the groundwater for enrichment. Furthermore, evaporation processes, groundwater depletion, and ion exchange contribute to the increased concentration of Na+ and Cl? ions in groundwater. Anthropogenic sources are one of the main reasons for contamination of groundwater in the study area and for increasing the concentration of Mg2+, Na+, Cl?, SO42?, and NO3? ions. Results show the quality of groundwater in the study area is categorized as follows: HCO3? + CO32? > Cl? > SO42? > NO3? > F? and Na+ > Ca2+ > Mg2+ > K+. In conclusion, the results of TDS, TH, and chemical composition showed that 26% of the groundwater samples were unsuitable for drinking. About 28% of groundwater samples in the study area have a high concentration of Mg2+, Na+, and NO3? above the acceptable limit. Also, based on high SAR, 10% of the groundwater samples were not suitable for irrigation purposes.  相似文献   

2.
In the present study, an attempt has been made to quantify the fenvalerate accumulated in different tissues (gill, muscle and liver) and observe changes involved in the levels of sodium, potassium and calcium ions and Na+–K+, Mg2+ and Ca2+ adenosine triphosphatase (ATPase) activities in the freshwater fish, Cirrhinus mrigala on short-term and long-term exposure to the median lethal and sublethal concentration of fenvalerate. Residue analysis using gas–liquid chromatography (GLC) technique revealed that fenvalerate accumulated in highest quantity in gill followed by liver and muscle under median lethal concentration (6?µg?L?1). Whereas in sublethal concentration (0.6?µg?L?1), muscle accumulated highest quantity followed by gill and liver, which might be due to the fact that fenvalerate is highly lyphophilic. The ion concentration and ATPase activity were found effected in fish exposed to lethal and sublethal concentrations of fenvalerate. Concentration of Na+, K+ and Ca2+ ions decreased in gill, muscle and liver on being exposed to median lethal concentration to a significant level. Whereas the changes were not highly pronounced at sub lethal level indicating low concentration of fenvalerate and its non-toxic effect at chronic exposure. Na+–K+, Mg2+ and Ca2+ ATPases activity were also found decreased in correspondence to the ionic change under median lethal and sub lethal concentrations in target tissues. This might have lead to behavioural changes and create wide-spread disturbance in the normal physiology, ultimately causing the death of the fish. The results suggest that in biomonitoring programmes, ions and associated ATPases can be a good diagnostic tool for fenvalerate toxicity.  相似文献   

3.
Attention is being focused on the coastline from Doha to Ras Laffan in Qatar since higher activities in the development of land and establishment of roads, highways and new buildings and houses is not coupled by serious studies on habitat destruction, fragmentation or disturbances. Ecophysiological study was carried out to investigate the adaptation of two halophytes (Limonium axillare and Avicennia marina) in this area, with special emphasis on the ultrastructure of salt glands found in the leaves. Soils in these locations accumulated much Na+ and Cl? as compared to other cations like K+, Ca2+ and Mg2+. Both plants accumulated higher concentrations of Na+ , Cl?, and Ca2+ and lower concentrations of K+ and Mg2+. Organic compounds found in leaves of these plants under their natural habitats including proline, soluble sugars and nitrogen, and photosynthetic pigments were determined. Scanning electron micrographs of the surface of leaves showed that salt glands of these plants are well developed. It is urgently required that exact vegetation maps, and monitoring exercises will be conducted, in order to document exactly the state of the vegetation in Qatar. Only this will allow the environment authorities to bring forward suggestions for vegetation and ecosystem management to the decision makers.  相似文献   

4.
5.
A. Oikari 《Marine Biology》1978,44(4):345-355
Hydromineral regulation was studied by examining the response to different environmental salinities in two Baltic brackish-water (BW) teleosts—a species of marine ancestry, Myoxocephalus scorpius (L.), and a glacial relict, M. quadricornis (L.). M. scorpius tolerated fresh water (FW) and M. quadricornis sea water (SW) for only about 24 h, but the survival time of M. scorpius in SW and M. quadricornis in FW was one to several weeks. M. scorpius seems able to balance plasma ionic concentrations in salinities down to about 2 to 3. Death of M. scorpius in FW was associated with partial haemolysis, increased volume of red blood cells (RBC), increased plasma K+ concentration, and decreased concentrations of Na+, Cl- and Mg2+ in plasma and, to a lesser extent, in urine. Death of M. quadricornis in SW was associated with increased plasma osmolality, and Na+, Cl- and Mg2+ concentrations, but the renal excretion of ions approached that generally found in marine teleosts. In most cases, RBC volume followed the changes in plasma osmolality or Na+ and Cl- concentrations. Both species showed an ability to increase tubular Mg2+ secretion much over that needed in BW, and increased secretion was associated with high urine Cl- concentration. M. quadricornis, but not M. scorpius, reabsorbed Na+ effectively in SW also. Differences between Oceanic and Baltic specimens of M. scorpius are discussed.  相似文献   

6.
The effect of feed seawater temperature on the quality of product water in a reverse osmosis process was investigated using typical seawater at Urla Bay, Izmir region, Turkey. The tests were carried out at different feed seawater temperatures (11–23°C) using two RO modules with one membrane element each. A number of variables, including pH, conductivity, total dissolved solids, salinity, rejection percentage of a number of ions (Na+, K+, Ca2+, Mg2+, Cl, HCO3 , and SO4 2−), and the levels of boron and turbidities in collected permeates, were measured. The suitability of these permeates as irrigation and drinking water was checked by comparison with water quality standards.  相似文献   

7.
Previous studies have demonstrated that cadmium can induce biochemical and physiological changes in yeast Saccharomyces cerevisiae. However, studies on the influence of cadmium on the ion balance in the cell and the interaction between cadmium and other ions are still relatively few in number. By using inductively coupled plasma-atomic emission spectrometry, the contents of some cations, including Zn2+, Ca2+, Fe3+, Cu2+, Mg2+, K+, and Na+ were measured. The data showed that the levels of Zn2+ and Fe3+ were increased, while those of Cu2+, K+, and Na+ were decreased after cadmium treatment. Afterwards, using the drop test assay, the interactions between cadmium and the selected ions were investigated. The results suggested that the cytotoxicity of cadmium could be attributable to the interference of cadmium with the intracellular cation homoeostasis. Calcium channel transporter Cch1 participates in the intracellular uptake of cadmium. Additionally, Zn2+, Ca2+, Fe3+, Mg2+, and K+ can rescue the toxic effect of cadmium in yeast.  相似文献   

8.
Nineteen years (1980–1998) of precipitation chemistry data from a site in Alaska are examined for trends using a least squares general linear model. The annual concentrations of SO2– 4 show a significant decreasing trend at 0.001 level and the annual change in concentration is —0.012mg 1–1 yr–1. The annual concentrations of NO 3 show an increasing tendency non‐significant. The annual base cation concentrations show a clear significant decreasing trend at 0.001 level and the decrease is —0.009mg 1–1 yr–1. Ca2+ concentrations exhibit a significant decreasing trend at 0.001 level and the annual change of concentration is —0.003 mg 1–1 yr–1. Mg2+ and Na+ concentrations show a significant decreasing trend at 0.01 level and the annual change is —0.001 mg1–1 yr–1 for Mg2+ and —0.004 mg1–1 yr–1 for Na+. K+ concentrations are characterised by a decreasing trend, significant at 0.05 level. K+ concentrations have decreased —0.002mg1–1 yr–1. The strongest rates of concentration decline for base cations, Ca2+, Mg2+, K+ and Na+ occurred in fall and winter season. The annual values of pH show a decreasing trend non‐significant. The values of pH oscillate between 5.1 and 5.6 during the period considered.  相似文献   

9.
Specimens of Chlamys opercularis, Modiolus modiolus, Mytilus edulis, Crassostrea gigas, Scrobicularia plana and Mya arenaria were exposed to both gradual (sinusoidal) and abrupt (square-wave) salinity fluctuations and measurements made of osmotic, Na+, Mg2+ and Ca2+ concentrations in the hemolymph and where applicable in the mantle fluid. In both sinusoidal and square-wave regimes fluctuating between 100 and 50% seawater (100%=ca. 32 S), the hemolymph Na+, Mg2+, Ca2+ and osmotic concentrations followed the concentrations of the external medium in Chlamys opercularis. The hemolymph and mantle fluid osmotic Na+, Mg2+ and Ca2+ concentrations of Modiolus modiolus, Mytilus edulis, Crassostrea gigas and S. plana followed those of the external medium as long as the molluscs' shell valves remained open. There were no changes in the ionic or osmotic concentrations of the hemolymph or mantle fluid of any of these species during periods of shell-valve closure. The hemolymph osmotic, Na+ and Mg2+ concentrations of wedged-open Modiolus modiolus, Mytilus edulis, C. gigas and S. plana followed those of the external medium. Hemolymph Ca2+ concentrations showed a damped response in C. gigas and Mytilus edulis. The hemolymph osmotic, Na+, Ca2+ and Mg2+ concentrations of Mya arenaria fluctuated in a similar manner to the external medium, but were damped. Wedged-open Mytilus edulis exposed to fluctuating salinity and supplied with a constant supply of 10 mM Ca2+ showed greater changes in hemolymph ionic and osmotic concentrations than M. edulis exposed to the same salinity fluctuation without a constant Ca2+ supply. Chlamys opercularis and Modiolus modiolus survived in a 50% seawater minimum sinusoidal salinity fluctuation for 10 days; wedged-open M. modiolus survived only 3 days. Burrowing had no effect on the osmotic, Na+, Mg2+ or Ca2+ concentrations of the hemolymph of Mya arenaria or S. plana exposed to fluctuating salinities. All of the species studied were shown to be osmoconformers.  相似文献   

10.
The aim of this study is to investigate the differences in the chemical conditions of lotic waterbodies in the two major ecosystems in Nigeria, the forest and savanna zones. The forest waters were slightly acidic (mean±SD pH = 6.72±0.58) while the savanna waters were slightly alkaline (pH = 7.11±0.33). The cationic order of dominance in the forest waters was Na+ > Ca2+ > Mg2+ > K+ in contrast to Ca2+ > Mg2+ > Na+ > K+ in savanna waters. The forest waters were chlorided (typical of coastal and/or marine waters) whereas the savanna waters were carbonated in nature, typical of the worldwide freshwater. Organic carbon was significantly higher in forest waters than in the savanna waters (p < 0.05) while nutrient compounds were significantly higher in savanna waters than in forest waters. The seasonal variation of the chemical parameters was generally more evident in savanna than in forest waters. The differences in water quality between the two major vegetation zones reflect the differences in the biogeochemical processes and nutrient cycling that characterise forest and savanna ecosystems.  相似文献   

11.
The development of industry in Beijing, the capital of China, particularly in last decades, has caused severe environmental pollution including particulate matter (PM), dust–haze, and photochemical smog, which has already caused considerable harm to local ecological environment. Thus, in this study, air particle samples were continuously collected in August and December, 2014. And elements (Si, Al, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Cd, Ba, Pb and Ti) and ions (\({\text{NO}}_{3}^{-}\), \({\text{SO}}_{4}^{2-}\), F?, Cl?, Na+, K+, Mg2+, Ca2+ and \({\text{NH}}_{4}^{+}\)) were analyzed by inductively coupled plasma mass spectrometer and ion chromatography. According to seasonal changes, discuss the various pollution situations in order to find possible particulate matter sources and then propose appropriate control strategies to local government. The results indicated serious PM and metallic pollution in some sampling days, especially in December. Chemical Mass Balance model revealed central heating activities, road dust and vehicles contribute as main sources, account for 5.84–32.05 % differently to the summer and winter air pollution in 2014.  相似文献   

12.
Rainwater samples were collected from Tamale town in the 1997 and 1998 rainy seasons. During this period road construction in the Tamale area resulted in the generation of suspended dust in the atmosphere. Analysis of the samples for major ions showed elevated levels of Cl. Ion ratios with Cl (Na+/Cl, K+/Cl, Ca2+/Cl/Cl Mg2+/Cl and SO4 2–/Cl) in rainwater samples were higher than the corresponding ratios in seawater. Some samples also showed elevated concentrations of Fe, Mn, Al and Zn, all of which except Zn showed a correlation with the dry periods between rainfall events. Consequently, it was concluded that dust generated from lateritic soils was probably the major cause of the increase in concentration of these metals. Aluminium and Fe concentrations were observed to be higher than the World Health Organization drinking water guide limits.  相似文献   

13.
A laboratory-scale investigation was performed to study arsenic (As (V)) removal by negatively charged GE-HL nanofiltration (NF) membrane in simulated drinking water. Effects of As (V) concentration (0–200 μg·L?1), pH, and co-ions and counter-ions were investigated. The NF membrane presented good stability, and the rejection rates exceeded 90%. The rejection rates of As (V) decreased with the increase of As (V) concentration, while it increased with the increase of pH (reached 96% at pH 6.75). Moreover, a negative relationship was observed between the co-existing ions of Cl?, Na+, SO 4 2? , and Ca2+ and the removal of As (V), in which bivalent ions presented more significant effects than monovalent ions.  相似文献   

14.
This research deals with the sulfurous spring waters flow along the course of the Euphrates River in western Iraq in the area extended between Haqlaniya and Hit within the Al-Anbar governorate. Eleven springs (3 in Haqlanya, 4 in Kubaysa and 4 in Hit) have been addressed for the purpose of water evaluation for balneology, drinking, irrigation and aquaculture (fish farming). In order to meet the objectives of this research, all springs were sampled and analyzed for the total dissolved solid, electrical conductivity, pH, temperature, major cations (Ca2+, Mg2+, Na+ and K+), major anions (SO4 2?, Cl?, HCO3 ? and CO3 2?), minor anions (PO4 3?and NO3 ?) as well as the trace elements that included Pb, Zn, Cd, Ni, Fe, Mn, Cu, Br, F, Ba, B, Sr, Al, As, Cr, Hg and Se. The International Standards of World Health Organization are used for assessing the water quality. The results revealed that the springs belong to the tepid springs of 27–30 °C and classified as hypothermal to the thermal springs. Lithochemistry and geochemical processes clearly affected the water chemistry. The hydrogeochemical processes are responsible for the element enrichment in water by the chemical dissolution of carbonate and gypsum and evaporation as well. The results of the study indicate the possibility of using spring water for therapeutic purposes, but not allowed for drinking and aquaculture (fish farming), except those free of H2S gas. On the other hand, it can be used for irrigation with risk. However, soil type as well as proper selection of plants should be taken into consideration.  相似文献   

15.
Osmotic pressure and major ions (Cl, Na+, Mg2+, Ca2+) of the egg capsule fluid in the slipper limpet Crepidula fornicata were investigated in relation to embryonic development. Calcium permeability of the capsule wall was studied at oviposition, by dipping freshly laid egg capsules in 45Ca as a tracer. This study also determined total calcium content of the embryos at different developmental stages. Osmolarity and major ion concentrations in egg capsule fluid were higher than seawater at uncleaved and trochophore stages, and then dropped to the same level as sea water at veliger stage. Concentrations of Cl and Na+ were relatively high at oviposition, peaked at trochophore stage, and finally dropped close to concentrations of seawater at hatching. In contrast, concentrations of Mg2+ and Ca2+ decreased steadily during capsular development. Radiotracer permeability experiments in freshly laid egg capsules confirmed that the capsule wall is impermeable to this ion at that stage. However, because of the dissolution of the inner layer of the wall during the final part of capsular development, the wall becomes permeable to calcium and probably to the rest of the major ions studied.  相似文献   

16.
The uptake and effect of dissolved copper on regulation of hemolymph osmolality and Na+, K+, Cl-, Ca++, and Mg++ concentrations in the shore crab Carcinus maenas (L.) were determined at 400 mOsm (=14 S) ambient salinity. One mg Cu l-1 resulted in 50% mortality in 11 to 22 d; the highest sensitivity was observed around the moulting period. 0.25 and 0.5 mg Cu l-1 were not lethal after a onemonth exposure. Ten, 1, and 0.5 mg Cu l-1 altered regulation of osmolality, Na+, K+, and Cl- concentrations, while 0.25 mg Cu l-1 did not. Exposure to 1 mg Cu l-1 reduced hemolymph osmolality and Na+, K+, and Cl- concentrations to 80 to 90% of controls within 4 to 6 d and no further reduction was observed during a 21-d exposure. The effect of various copper concentrations on these four parameters were almost identical and the highest sensitivity was observed around the moulting period. Hemolymph calcium levels increased 20 to 80% in crabs exposed to 1 mg Cu l-1, while they decreased 20 to 30% in crabs exposed to 0.5 mg Cu l-1. Prolonged exposure to copper caused 20 to 70% reductions in hemolymph magnesium levels. Crabs exposed to 0.5 mg Cu l-1 for 29 d accumulated copper in hepatopancreas, gills, carapace, heart, testes, and hypodermis, but not in muscles and hemolymph. Increased copper levels in crabs exposed to 0.25 mg Cu l-1 were observed in hepatopancreas, gills, and carapace only. The present results suggest that effects of copper on ion regulatory processes in part explain why the toxicity of copper towards euryhaline invertebrates increases at low salinities.  相似文献   

17.
18.
A model is proposed to provide a simple, yet quantitatively valid perspective for the extent of soil (and lake) acidification to be expected for chemically and biologically active soils under the threat of acid precipitation. The model attempts to predict the acid (H+ + Al3+ + Fe3+) and base (Na+ + K+ + Mg2+ + Ca2+) cation losses from the soil, calculated from the rate and amount of acid cation retention when the rate of acid cation input is constant. It is assumed that the total amount of acidity retained by the soil is limited and qualitatively follows a Freundlich-type “absorption” isotherm. Required input information for the model includes (i) the total amounts of acid and base cations received by the soil via precipitation and weathering (minus normal leaching losses), (ii) the exchangeable base cation content and total number of cation exchange sites of the soil prior to the onset of acid precipitation.  相似文献   

19.
An area with extremely high incidence of urinary calculi was investigated in the view of identifying the relationship between the disease prevalence and the drinking water geochemistry. The prevalence of the kidney stone disease in the selected Padiyapelella–Hanguranketa area in Central Highlands of Sri Lanka is significantly higher compared with neighboring regions. Drinking water samples were collected from water sources that used by clinically identified kidney stone patients and healthy people. A total of 83 samples were collected and analyzed for major anions and cations. The anions in the area varied in the order HCO3 ? > Cl? > SO4 2? > NO3 ? and cations varied in the order Ca2+ > Mg2+ > Na+ > K+ > Fe2+. The dissolved silica that occurs as silicic acid (H4SiO4) in natural waters varied from 8.8 to 84 mg/L in prevalence samples, while it was between 9.7 and 65 mg/L for samples from non-prevalence locations. Hydrogeochemical data obtained from the two groups were compared using the Wilcoxon rank-sum test. It showed that pH, total hardness, Na+, Ca2+ and Fe2+ had significant difference (p < 0.005) between water sources used by patients and non-patients. Elemental ratio plots, Gibbs’ plot and factor analysis indicated that the chemical composition of water sources in this area is strongly influenced by rock–water interactions, particularly the weathering of carbonate and silicate minerals. This study reveals a kind of association between stone formation and drinking water geochemistry as evident by the high hardness/calcium contents in spring water used by patients.  相似文献   

20.
Osmoregulatory ability of mature chum salmon (Oncorhynchus keta) during spawning migration was examined by following the changes in gill Na+, K+-ATPase activity and in the distribution and morphology of chloride cells. Mature chum salmon caught in Otsuchi Bay, northern Honshu Island, Japan, died within 5 d in seawater (SW) in association with a marked increase in plasma osmolality, whereas the fish transferred to fresh water (FW) maintained plasma osmolality efficiently. Gill Na+, K+-ATPase activity decreased in both SW-maintained and FW-transferred fish. Well-developed chloride cells, identified by immunocytochemical staining specific for Na+, K+-ATPase, were present mainly in the filament epithelium of immature fish caught in the ocean. In mature fish caught in the bay, however, additional chloride cells were also found in the lamellar epithelium. The number of filament chloride cells decreased markedly in the mature fish both in SW and in FW, whereas the number of lamellar chloride cells was maintained. These results suggest that the loss of hypoosmoregulatory ability in mature chum salmon may be attributable to the decrease in filament chloride cells and associated decrease in gill Na+, K+-ATPase activity, and also that appearance of lamellar chloride cells may be preparatory to the forthcoming upstream migration. Received: 14 April 1997 / Accepted: 5 May 1997  相似文献   

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