浅层地下水水化学特征与土体盐分相关性研究

为研究南通地区浅层地下水与土体盐分特征的相关性,采集了31件水样、220件土样,并收集了60组水质资料,分析了浅层地下水水化学特征和土体盐分特征。研究表明:浅层地下水自西向东,TDS逐渐增大,主要为咸水和盐水,水化学类型为Cl—Na型,TDS与各离子(K⁺、Na⁺、Ca²⁺、Mg²⁺、Cl^-、SO₄^2-)的相关性高;土体盐分特征和地下水基本相似,自西向东逐渐增大,随着深度的加深也逐渐增大,盐渍土类型为氯盐渍土,以弱盐渍土为主,表明土体中的盐分主要来自于地下水;地下水的TDS和土体的总盐量、K⁺、Na⁺、Mg²⁺、Cl^-、SO₄^2-的相关性都很高,为此建立多个关于TDS与土体盐分特征的线性预测模型,平均相关系数达0.839,平均预测准确率达到了88.93%,效果良好,从而可在不钻探成井的条件下,依靠采取的土样判断地下水的TDS,节省了钻探成井的费用。     

基于多元统计方法的新疆巴里坤盆地地下水水化学特征及其影响因素分析

多元统计方法能同时对多个变量进行分析研究,是一种可用于地下水水化学特征相关分析的有效工具。基于12组水样的9项指标,运用多元统计方法系统分析了新疆巴里坤盆地地下水水化学特征及其影响因素。结果表明：该地区内主要分布低矿化度的HCO₃·SO₄-Ca·Na型水（占总取样点的33.3%）和HCO₃·SO₄-Ca型水（占总取样点的25.0%）,地下水中各离子的空间变异性为中等以上。地下水水化学特征主要受以Na⁺、Ca²⁺、Mg²⁺、Cl^-、SO₄^2-、总硬度（TH）、溶解性总固体（TDS）为主要荷载变量的蒸发浓缩作用和以HCO^-₃为主要荷载变量的溶滤作用影响,两种作用的贡献率分别达76.17%和14.87%。研究结果可为当地地下水资源的保护和可持续利用提供科学依据。     

Hydrochemistry of Lake Rara: A high mountain lake in western Nepal

High altitude ecosystems have important natural ecological functions but are under increasing impacts from human activities and climate change. A detailed analysis of the water chemistry of Lake Rara, a high mountain lake in western Nepal, was carried out in October 2015 and April 2016. A total of 31 water samples were collected. Major ions (Ca²⁺, Mg²⁺, Na⁺, K⁺, SO₄^2?, NO₃^? and Cl^?) were analysed by ion chromatography. Si and PO₄^3? were analysed following the standard protocols. Conductivity, pH, total dissolved solids (TDS), turbidity and dissolved oxygen (DO) were measured on‐site. The lake is oligotrophic characterized by low PO₄^3? concentration (0.06 ± 0.01 mg/L), high DO values (6.73 ± 0.06 and 10.89 ± 0.86 mg/L), alkaline pH (8.42 ± 0.3 and 8.32 ± 0.23) and low conductivity (189.93 ± 5.3 and 189.22 ± 5.8 μS/cm). The concentrations of the major cations were in the order of Ca²⁺ > Mg²⁺ > K⁺ > Na⁺ (during both seasons), and for anions, it was HCO₃^? > SO₄^2? > Cl^? > NO₃^? and HCO₃^? > Cl^? > NO₃^? > SO₄^2? during postmonsoon and premonsoon, respectively. One‐way ANOVA revealed significant seasonal variations (p  < 0.05) in most of the physicochemical parameters. The increased concentrations of most of the ions in the premonsoon time probably reflect long‐range transport of materials through dry deposition, whereas higher concentrations of NO₃^? and Cl^? in some sites possibly reflect the localized impacts of settlement and grazing. The lake water was classified as Ca(Mg)HCO₃. High (Ca²⁺ + Mg²⁺)/Tz⁺ ratio (0.97 in postmonsoon and 0.95 in premonsoon) and low (Na⁺ + K⁺)/Tz⁺ ratio (0.03 in postmonsoon and 0.04 in premonsoon) confirm carbonate weathering as the principal source of major ions with bedrock geology governing the water chemistry. The findings of this study build on the baseline dataset for assessing future anthropogenic influence on the lake and subsequent development for future lake management strategies.     

Assessment of the Impact of Municipal Solid Waste on Groundwater Quality near the Sangamner City using GIS Approach

The present work aims at assessing the impact of MSW on the groundwater quality around dumping yard site, located near the Sangamner city by water quality index (WQI) and its integration in geographical information system (GIS). Groundwater samples (n?=?15) around the dumping yard were collected using Garmin GPS device in October 2013 and October 2014. Physico-chemical analysis of same samples was carried out for pH, EC, TDS, Na⁺, K⁺,Ca²⁺, Mg²⁺, TH, Cl^?, HCO₃ ^?, SO₄ ^2? and NO₃ ^? along with the heavy metals like Fe, Zn, Cd and Cr by using standard methods. Similarly, SAR, KRs, RSC and SSP were also calculated to know the groundwater quality into irrigation perspective. WQI for 15 samples were calculated using physico-chemical results/data of 12 parameters and its desirable limit of BIS standard. Generated WQI (z) for October 2013 and October 2014 were integrated with latitude (y) and longitude (x) values, collected using GPS during the field work. Integrated xyz data were then interpolated in Surfer-10 GIS software using inverse distance weight (IDW) method to estimate the groundwater quality of the study area. Study revealed that the groundwater quality around the dumping yard area does not confirm to drinking and domestic purposes as per the WQI and BIS standard. However, the groundwater quality is marginally suitable for irrigation as per SAR, KRs, RSC and SSP. The influence of leachate from MSW dumping site to surrounding groundwater is creating a serious concern and susceptible to potential health hazards. Thus, continuous monitoring of groundwater is desperately required in order to minimize the groundwater pollution for control the pollution-caused MSW.     

新疆和田河流域绿洲区浅层地下水水化学特征及成因分析

以和田河流域绿洲区2014年44组浅层地下水样的化学数据为基础,运用描述性统计分析法、Piper三线图、Gibbs图和离子比值法对该区浅层地下水水化学特征进行了分析研究。结果表明,研究区地下水呈中性-偏碱性,大部分为硬度较高的微咸水,且处于氧化状态下。常见阳离子的含量差别较大,由大到小依次为Na~+Ca~(2+)Mg~(2+)K~+;常见阴离子的含量差别不大,由大到小依次为HCO_3~-Cl~-SO_4~(2-)。沿地下水流程从强径流区到弱径流区,离子的含量越来越多,TDS逐渐升高,水化学类型从混合型转变为以Cl-Na型和Cl·HCO_3-Na·Ca型为主。影响研究区地下水化学成分形成和变化的因素主要有蒸发浓缩作用、溶滤作用、阳离子交替吸附作用及人类活动。     

重庆老龙洞岩溶地下水化学特征及影响因素

为研究老龙洞地下河出口(G3)与表层岩溶泉(G1、G2)水化学特征差异及影响因素,利用统计方法对2012年月尺度的水化学数据进行分析。结果表明:研究区地下水水化学组成以Ca~(2+)、Mg~(2+)、HCO_3~-、SO_4~(2-)为主,水化学类型主要为Ca-HCO_3型;Ca~(2+)、Mg~(2+)、HCO_3~-浓度变异系数较小,主要来源于碳酸盐岩地层溶蚀,且以石灰岩溶解为主;硫酸与硝酸参与了碳酸盐岩的溶蚀,其中硫酸对碳酸盐岩溶蚀的影响更大;地下水中SO_4~(2-)、PO_4~(3-)、Na~+、K~+、Cl~-和NO_3~-浓度变异系数较大,主要受农业施肥、畜禽粪便、企业废水和生活污水等因素的影响;SO_4~(2-)、PO_4~(3-)、Na~+、K~+、Cl~-浓度表现为地下河高于表层岩溶泉,而NO_3~-浓度表现为地下河低于岩溶泉。     

Effects of diversion on the chemistry of a stream in Japan

On the upper reaches of the Ishite River, Japan the stream water is diverted completely at about 3 km above the Ishitegawa Reservoir, except under flood conditions. The chemical composition of the regenerated streamflow 2.4 km downstream from the diversion was determined 70 times during two years (1986-7) to investigate the effects of the diversion on water chemistry. Factor analysis suggested that two main factors controlled the water chemistry. Factor 1 explained 45.7% of the total variance and was correlated positively with the concentrations of Ca²⁺, Mg²⁺, Na⁺, HCO^? ₃, SO^2? ₄ and Cl^?, which seemed to reflect the leaching of dominant ions from the catchment soil. The factor 1 score was correlated negatively with the ecological ‘Ca-Mg index’ (r² = 0.912), a low value of which is necessary to avoid phosphorus enrichment by phytoplankton in the downstream reservoir. The diversion seemed to contribute to this purpose because the log flow-rate value was correlated positively with the index (r² = 0.730). On the other hand, factor 2 explained 10.2% of the total variance and was correlated positively with NO^? ₃ concentration and negatively with pH. Factor 2 was considered in relation to the partial pressure of dissolved CO₂ gas in the stream water and appeared to be a complex biological factor that reflected CO₂ production in the catchment soil and consumption in the stream.     

Distribution and geochemical processes of boron in the multimedia of Lake Qinghai,China

Lake Qinghai on the Qinghai-Tibet plateau is the largest lake in China. This study investigated the concentration and geochemical processes of boron (B) in lake water, lake sediment and river samples collected from Lake Qinghai and the Buha River. In addition, lake sediment pore water samples were analyzed. The concentrations of B and major ions, including K⁺, Na⁺, Ca²⁺, Mg²⁺, Cl^? and SO₄^2?, were analyzed in all the water samples. The average concentration of B was 0.07?mg?L^?1, 6.37?mg?L^?1, 12.79) mg?L^?1 and 59.42?mg?kg^?1 for river water, lake water, pore water, and sediment, respectively. There were significant (p?<?0.05) and positive (r?=?0.70) relationships between the B concentrations in bottom water of the lake and in lake sediment, indicating that B diffusion from the sediment plays an important role in the concentration of B in bottom lake water. The differences in B concentrations and B/major ion molar ratios of the river water, lake water, and pore water indicated the following geochemical processes: 1) B is enriched in the lake water through evaporative concentration; 2) B is removed from the lake water through mineral precipitation as well as sorption onto colloids; 3) Solid-phase B in sediments was released through dissolution driven by organic matter mineralization. B/Cl and Na/Cl molar ratios alone are not enough to identify the sources of B in the water of inland closed-basin saline lakes because of these processes.     

Water quality in the southern Tibetan Plateau: chemical evaluation of the Yarlung Tsangpo (Brahmaputra)

Yarlung Tsangpo (Brahmaputra) is the largest river system draining the northern slopes of the Himalayan ranges on the southern Tibetan Plateau. It remains one of only two large non‐regulated rivers in China. In this paper the chemical composition of Yarlung Tsangpo and its major tributaries (Raga Tsangpo, Nyangchu and Lhasa River) are studied. Water samples (n = 55) were collected and measured for major ions, trace elements and nutrients in order to: (1) define the present chemical quality of this water course; (2) address possible mechanisms governing the water chemical compositions, and (3) identify potential sources for contaminants. Multivariable analysis shows that geology and climate are the major explanatory variables for the spatial variation in water chemistry in this river system. In general, water chemistry is mainly controlled by carbonate weathering, with Ca²⁺ and HCO being the dominant ions. In addition, runoff from brackish/saline lakes and geothermal waters, enriched in Na⁺, Cl^?, SO, Mg²⁺ and Li, are major contributors of elevated concentrations of these solutes in the headwater regions resulting in a relatively high loading of total dissolved solids (TDS, 146–397 mg L^?1). Levels of most heavy metals and total dissolved nutrients were generally found to be low. However, elevated As concentration (avg. 95 μg L^?1) in the headwaters and additions from untreated wastewater were evident at some locations. Copyright © 2009 John Wiley & Sons, Ltd.     

应用非参数的MK和ITA方法分析地下水水质参数变化特征——以新三矿含水层为例

矿区地下水水质变化是影响矿区生态环境和矿井安全生产的制约因素之一,正确认识水质变化趋势是首要任务。根据以往实测水质参数pH、COD、Na~++K~+、Ca~(2+)、Mg~(2+)、Cl~-、SO_4~(2-)和HCO_3~-的数据,采用Mann-Kendall检验法(MK)和Innovative Trend Analysis(ITA)探讨新三矿由上而下6个不同含水层水质参数随时间的演变规律,并且针对不同的数值变化范围选用不同的ITA指数。通过比较,两种方法结果有很好的一致性,结论认为:相比MK检测法,定量的ITA法拥有更多的优点,可以图形化地表示分析结果,可以通过将水质参数值分为低、中、高水平更好地分析水质参数的趋势和次要趋势;8种水质参数中,Ca~(2+)和Mg~(2+)相较其他离子能表现出更显著的变化趋势;6种含水层中,大青灰岩含水层中Cl~-浓度的低、中值下降而高值上升,煤层顶板山西组砂岩含水层和底板奥陶系灰岩含水层大部分水质参数显著下降,矿化度逐渐降低。     

Study of water quality of springs in Petra region,Jordan: A three-year follow-up

Petra region area was located in south part of Jordan has grown and urbanized rapidly. This area depends on the groundwater as a water resources. This study was undertaken to assess the physical, chemical quality of spring water of Petra region during a 36-months survey (September 2002 to September 2005). The samples were analyzed for temperature, conductivity, dissolved oxygen, pH, major cations (Ca²⁺, Mg²⁺, K⁺, and Na⁺), major anions (Cl⁻, NO⁻ ₃, HCO⁻ ₃, SO²⁻ ₄, PO³⁻ ₄, F⁻) and trace metals (Fe²⁺, Al³⁺, Cu²⁺, Ni²⁺ Pb²⁺, Zn²⁺ and Mn²⁺). Water quality for available springs in the study area showed high salinity due to longer period of contact with rocks. The chemistry of spring water samples were alkaline earth waters with prevailing bicarbonate and alkaline earth waters with prevailing bicarbonate chloride. Some springs showed that elevated nitrate, sulfate contents which could be due to percolation from septic tanks, cesspools and irrigational activities. The infiltration of wastewater from cesspools and septic tanks into groundwater was considered the major source of water pollution. The results showed that there were considerable variations among the examined samples with respect to their physical and chemical parameters, which lie below the maximum permissible levels of the Jordanian and WHO drinking water standards. The results indicate that the trace metals of springs water of Petra region do not generally pose any health or environmental problems.     

The dying Dead Sea: The microbiology of an increasingly extreme environment

The Dead Sea, on the border between Israel and Jordan, currently contains around 348 g salt L^?1. Divalent cations (Mg²⁺, Ca²⁺) dominate over monovalent cations (Na⁺, K⁺), while Cl^? and Br^? are the main anions. The pH of the Sea is about 6. The water balance of the lake is negative, having dropped over 1 m year^?1 over the past decade. The water is supersaturated with Na⁺, with massive quantities of halite precipitating to the bottom of the lake. Biological monitoring since 1980 has indicated that blooms of the unicellular green alga Dunaliella and halophilic Archaea of the family Halobacteriaceae only develop following significant dilution of the upper water layers in the lake after very rainy winters. Such events occurred in 1980, and even more dramatically in 1992, when up to 3.5 × 10⁷ Archaea mL^?1 in the diluted upper 5–10 m of the water column coloured the lake red. Species isolated from the lake include Haloferax volcanii, Haloarcula marismortui, Halorubrum sodomense and Halobaculum gomorrense. Dunaliella was no longer observed in the lake after 1996, with prokaryote numbers remaining low. To characterize the residual microbial community in the lake, biomass was collected in February 2007 for environmental genomic analyses. The results were compared with the metagenome of microbial bloom material collected in 1992. The 16S rRNA archaeal phylotypes recovered from the 2007 sample were diverse, with phylotypes distantly related to the genera Halorhabdus, Haloplanus, Natronomonas and others. Halorhabdus sp. also was recovered in culture. The 1992 bloom sample was very homogeneous, however, with a single cluster remotely related to Halobacterium salinarum. These results illustrate that the microbial communities are dynamic, even in one of the most extreme environments on Earth, and exhibit strong shifts in species composition as conditions for life become increasingly adverse.     

Diffusion analysis and modeling of kinetic behavior for treatment of brine water using electrodialysis process

In this study, the removal of monovalent and divalent cations, Na⁺, K⁺, Mg²⁺, and Ca²⁺, in a diluted solution from Chott-El Jerid Lake, Tunisia, was investigated with the electrodialysis technique. The process was tested using two cation-exchange membranes: sulfonated polyether sulfone cross-linked with 10% hexamethylenediamine (HEXCl) and sulfonated polyether sulfone grafted with octylamine (S-PESOS). The commercially available membrane Nafion® was used for comparison. The results showed that Nafion® and S-PESOS membranes had similar removal behaviors, and the investigated cations were ranked in the following descending order in terms of their demineralization rates: Na⁺ > Ca²⁺ > Mg²⁺ > K⁺. Divalent cations were more effectively removed by HEXCl than by monovalent cations. The plots based on the Weber–Morris model showed a strong linearity. This reveals that intra-particle diffusion was not the removal rate-determining step, and the removal process was controlled by two or more concurrent mechanisms. The Boyd plots did not pass through their origin, and the sole controlling step was determined by film-diffusion resistance, especially after a long period of electrodialysis. Additionally, a semi-empirical model was established to simulate the temporal variation of the treatment process, and the physical significance and values of model parameters were compared for the three membranes. The findings of this study indicate that HEXCl and S-PESOS membranes can be efficiently utilized for water softening, especially when effluents are highly loaded with calcium and magnesium ions.     

咸水在黏性土中迁移转化的试验研究

采用衡水地下水科学试验场浅层钻孔土样进行室内一维土柱渗流试验,并用地球化学模拟方法探讨黏性土对咸水迁移转化的控制机理。结果表明:黏性土对咸水迁移有一定的阻隔作用,1号土柱对Na+的阻滞作用以吸附为主,2号土柱对Na+的阻滞作用由吸附和阳离子交换共同影响;1号和2号土柱的阻盐率分别为49.8%和54.5%;1号和2号土柱中黏性土的阻滞因子R1和R2分别为1.54和3.78;咸水迁移过程中,控制水岩相互作用的主要因素是岩盐的沉淀,石膏、方解石的溶解,Mg2+、Ca2+与Na+之间的离子交换。     

Assessment of the levels of coastal marine pollution of Chennai city,Southern India

The levels of hydrological pollution of Chennai coastal zone in the southeastern part of India have been increased in the recent years by an uncontrolled disposal of wastewater and pollutants due to human activities. This study gave a special emphasis on the determination of the levels of pollution, the identification of vulnerable zones and providing some probable remedial measures for severely impacted coastal zone of Chennai city. During the period from September to November 2002, sampling was carried out along the shore in two traverses running in the seaside (surf zone) and landside (coastal aquifer). When sampling efforts took place the middle of the above period experienced a monsoonal storm over Chennai coast that significantly influenced large variations in the pollution level at both traverses in seaside and landside. Analysis of physical, chemical and biological parameter determinations indicated that the concentrations of dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), nutrients (nitrate, nitrite and phosphate), turbidity, maximum probable number (MPN) and chlorophyll a (Chl a) reached notably high levels at all sample locations before monsoonal storm prevailed over these areas during October 2002, which resulted in large fresh water input to the coastal system reducing the levels of pollution to some extent. Analysis of water samples collected during November apparently indicated that the concentrations of above parameters attained abnormal level and often exceeded the permissible limit of international standards. The concentrations of trace/toxic metals such as manganese, copper, nickel, lead, cadmium and cobalt also reached very high levels as a result of their sub-aqueous disposal to these areas, leading to further habitat and ecological destruction. On the other hand, analysis of groundwater samples collected from coastal aquifer for determination of certain chemical parameters such as Ca²⁺/Mg²⁺, Cl⁻/(CO²⁻ ₃+HCO ₃ ^-) and the ratio of total alkalinity (TA) and total hardness (TH) revealed that coastal groundwater appeared to be severely contaminated by saltwater intrusion as a result of overexploitation and enormous pressure imposed by monsoonal storm of October. Higher concentrations of toxic elements, for example, lead, nickel, cobalt and cadmium from the influence of industrial wastes and contaminated coastal waters, were also found to deteriorate the quality of coastal aquifer system. Based on detailed examination, four sites including Cuvum estuary, Adyar estuary, Kannikoil and Bharathiyar nagar are identified as highly venerable zones because of receiving a large quantity of municipal and industrial wastes. To reduce severe pollution levels in these areas it is therefore necessary to design and construct the submarine pipeline system to transport and disperse such a large quantity of waste materials to the deep open ocean areas.     

Anthropogenic‐induced shifts in salinity and nutrient status of two freshwater tropical lakes in India

An understanding of ongoing changes in salinity and nutrient status, as influenced by anthropogenic forcing factors, is important for integrated lake basin management (ILBM) and conservation of water resources in dry tropical regions. This study analysed a range of water quality attributes, including salinity, nitrate (NO₃^?), ammonia (NH₄ ⁺ ), phosphate (PO₄ ^{3 ?}) and dissolved organic carbon (DOC) in two freshwater lakes in Rajasthan, India for three consecutive years (2000–2002). Between‐lake comparisons indicated marked differences in most of the water quality variables. The pH in both study lakes remained above neutral. Water hardness, salinity and concentrations of total dissolved salts (TDS), chlorides, NO₃^?, NH₄⁺, PO₃^3? and DOC were high in Lake Udaisagar, which received inputs from agricultural drainage and urban–industrial releases. The DOC in Lake Baghdara, which drains a woodland catchment, was similar to that for Lake Udaisagar, indicating the role of allochtonous inputs in the build‐up of DOC. The results of this study indicated that increasing human interferences have increased the nutrient concentrations in Lake Udaisagar. This factor, coupled with extended periods of dryness, drives these two freshwater lakes towards a high salinity. This study provides evidence of a human‐induced salinity increase and has relevance for ILBM and for the conservation of freshwater resources in dry regions.     

阿拉尔灌区农田排水水质水量变化规律分析

农田排水资源化利用作为缓解淡水资源短缺与减小环境负面影响的有效途径已经被众多学者关注,所以,在农田排水资源化利用的前期就需掌握水质、水量变化规律。实验通过对阿拉尔灌区塔南总排农田排水两年采样,监测排水量、矿化度、Na~+、Cl~-等离子浓度并分析变化规律。结果表明:塔南总排农田排水水量丰富且逐月变化规律明显,2015、2016年总水量分别为0.75×10~8、0.69×10~8m~3;排水全年为咸水水质,两年平均矿化度8.7 g/L且矿化度变化规律与水量变化规律呈负相关;排盐量变化规律与排水量变化规律呈正相关,排渠两年向塔里木河排盐11.93×10~4t;排水属Na-Cl型水质,Na+为主要阳离子,平均占比16.7%,平均浓度1.4 g/L;Cl~-为主要阴离子,平均占比35.6%,平均浓度3.1 g/L。并提出了南疆农田排水资源化利用建议:农田排水水量较大月份排水的矿化度、Na~+、Cl~-浓度均较低,再利用时可优先考虑。     

Impact of Flood Spreading on Groundwater Level Variation and Groundwater Quality in an Arid Environment

In arid and semiarid areas, bimodal and high rainfall leads to infrequent flood that can be extremely damaging. To reduce the impacts of persistent intra-seasonal drought and also to reduce flood damaging in arid and semiarid areas, rainwater storage is a prerequisite that keeps water far from evapotranspiration, increases groundwater level and decreases flood hazards modification to exchange between surface water and groundwater through flood spreading, dams, etc. The purpose of this paper is to delineate and explain variations in groundwater recharge and groundwater quality along an ephemeral stream that has been modified by flood spreading. Groundwater samples were collected from 14 deep wells located at different distances from flood spreading projection area (FSPA) in 1 month interval during September 2005 to September 2008. Groundwater quality was followed via Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl^-, Hco₃^- SO₄^2-, Electrical Conductivity (EC) and pH measurements for two time periods between 2005 and 2008. The results show significant impact of flood spreading in groundwater table and groundwater salinity variation. Groundwater table decreased in all study wells, but groundwater drawdown increased by increasing the distance to FSPA (during 4 years study, 11.02 m in the well located at 20 m of FSPA versus 38.88 in the well located at 1,825 m). Also ion concentration increased in all of the wells during the study period, but the increasing ion concentration was significantly less important in FSPA closeness.     

Integration of Shuffled Frog Leaping Algorithm and Support Vector Regression for Prediction of Water Quality Parameters

Quality of surface water is a serious factor affecting human health and ecological systems. Accurate prediction of water quality parameters plays an important role in the management of rivers. Thus, different methods such as (support vector regression) SVR have been employed to predict water quality parameters. This paper applies SVR to predict eight water quality parameters including (sodium (Na⁺), potassium (K⁺), magnesium (Mg⁺²), sulfates (SO₄ ^?2), chloride (Cl^?), power of hydrogen (pH), electrical conductivity (EC), and total dissolved solids (TDS)) at the Astane station in Sefidrood River, Iran. To achieve an efficient SVR model, the SVR parameters should be selected carefully. Commonly, various techniques such as trial and error, grid search and metaheuristic algorithms have been applied to estimate these parameters. This study presents a novel tool for estimation of quality parameters by coupling SVR and shuffled frog leaping algorithm (SFLA) . Results of SFLA-SVR compared with genetic programming (GP) as a capable method in water quality prediction. Using SFLA-SVR, average of RMSE for training and testing of six combinations of data sets for all of the water quality parameters improved 57.4 % relative to GP. These results indicate that the new proposed SFLA-SVR tool is more efficient and powerful than GP for determining water quality parameters.     

Soluble Element Concentrations and Complexation in Southeastern Lake Michigan

Water samples were collected from the epilimnion and hypolimnion of southeastern Lake Michigan during 1974 and 1975. The mean elemental soluble (< 0.45 μm) concentrations in log₁₀ (moles per liter) of the 88 samples collected from the epilimnion are: Ba = ?6.5, Ca = ?3.1, Co = ?7. 7, Cr = ?7.5, Cu = ?7.4, Fe =?6.9, K =?4.5, Mg= ?3.3, Mn =?8.1, Mo =?6.9, Na =?3.6,Ni = ?6.9, Sr=?5.9, Zn =?7.1, Cl = ?3.5, soluble reactive PO₄^2?-P = ?7.5, SO₄^2? = ?3. 7, and soluble reactive SiO₂ = ?5.3. During the month of July in 1974 and 1975, the only variable having significant concentration differences between the epilimnion and the hypolimnion was soluble reactive SiO₂. It was more concentrated in the hypolimnion.Using thermodynamic data and solving simultaneous equations, the degree of complexation of each ion has been estimated. Ions which have 10% or more of their activity accounted for by complexes include Co²⁺, Cu²⁺, Fe³⁺, Mn²⁺,Ni²⁺, CO₃^2?, SO₄^2?,and HPO₄^2?. Using the resulting free ion activities and calculating solubility products, epilimnetic lake water during July 1974 from southeastern Lake Michigan is supersaturated with respect to dolomite, malachite, hydroxylapatite, fluorapatite, hydroxoapatite, X-ray amorphous Fe(OH)₃, and goethite. It is undersaturated with respect to calcite, aragonite, rhodochrosite, barite, and strengite.