A hydrochemical framework and water quality assessment of river water in the upper reaches of the Huai River Basin, China

This study characterizes the major ion chemistry for river water in the upper reaches of Bengbu Sluice in the Huai River Basin in wet and dry seasons, and assessed the suitability of water quality for irrigation and human consumption. It is found that sodium and calcium are the dominant cations and bicarbonate is the dominant anion in most river water samples. River water in Zhoukou of the Ying River and Bozhou of the Guo River is characterized as a Na–Cl water type, whereas river water from the upper reaches and the lower reaches of the two cities is characterized as a Na-HCO₃ water type, which may be attributed by anthropogenic influences in these cities. The river water types vary from the upstream to the downstream of the Fuyang sluice, which indicates that the sluices play a critical role in determining the water type. The water chemistry of these rivers clearly shows that the second group of rivers is affected more severely by waste effluent than is the first group. Calculated values of sodium adsorption ratio, %Na, and residual sodium carbonate indicate that, in general, most of the river water is of acceptable irrigation quality. The river water in Zhoukou section of the Ying River and the Bozhou section of the Guo River cannot be used as drinking water; pollution control should be further improved and enhanced across the river.     

基于不确定性分析框架的动态环状河网水质模型--以温州市温瑞塘河为例

以温州市温瑞塘河为背景,基于不确定性分析的框架,开发了动态环状河网水质模型。用HSY(Hornberger,Spear and Young)算法作水质参数的不确定性分析,求得模型参数的空间分布,从而提高模型使用的可靠性、降低决策的风险度。模型由水量子模型及水质子模型两部分组成:水量子模型采用圣维南方程并用四级解法求解;水质子模型采用CSTR(Continuously Stirred Tank Reactor)模型的机理,并结合环状河网特征作了修正,由于只需解常微分方程,因而避免了矩阵求解,显著提高了计算效率,使得用HSY算法进行不确定性分析成为可能。模型选取温州市温瑞塘河流域的鹿城区河网进行了首次应用,用HSY算法率定水质参数并讨论了参数的不确定性。对参数率定结果进行验证,结果比较理想。最后简要讨论了参数不确定性传递。     

Development of a framework of automated water quality parameter optimization and its application

This paper presents a methodology and framework for the development of an automated least-squares optimization tool for calibrating water quality parameters in QUAL2E. The method has been applied to estimate the optimal water quality parameters in simulation of stream water quality for the Anyang stream in Korea. The Monte Carlo analysis is used to assess the relative importance of model parameters for water quality constituents. It is found that μ_max and ρ are the most influential parameters for Chlorophyll-a modeling and K ₁ and K ₃ are critical parameters for variation of DO and BOD in the Anyang stream. A computer program for automated parameter calibration has been developed using a nonlinear GRG optimization algorithm. The application framework provides an intuitive and easy-to-use interface and allows visual evaluation of results. According to the simulation results, the automated approach is computationally efficient for evaluation of model parameters and converges on a best fit more rapidly and reliably than a trial and error method. The methodology proposed herein can be extended to other models to obtain the best possible parameter values.     

The impact of farming on river banks on water quality of the rivers

A study was carried out in a strip of a river in the dry and rainy seasons to assess the effect of farming along river banks on the quality of water in rivers. The results showed that there was an increase in the concentration of nitrate in the water downstream in both the rainy and dry seasons. In both rainy and dry seasons, the total nitrogen in the soil was highest (p<0.01) in the middle section. Significant seasonal differences (p<0.01) were observed for phosphate in water, being higher in the dry season. In the soil, the concentration of phosphate showed significant sectional differences (p<0.01) in the rainy season with the highest concentration observed in the lower section (1.74±0.01mg/l) and the least in the upper section (1.02±0.01g/l). However, in the dry season, the highest concentration was obtained in the middle section (1.69±0.01mg/l) and the least in the upper section (1.15±0.02 mg/l). The results suggest that the farms along the riverbanks have an impact on the water quality of the water in the river. It is therefore recommended that there should be close monitoring of the activities of the farms on riverbanks to minimise their impacts on the natural ecosystems that they interact with. Frequent monitoring of the water quality in the rivers relative to the farming estates should be done.     

Significance evaluation of factors controlling river water composition

In the present paper the factors controlling river water chemistry are described and their significance is evaluated, including: climate, petrography, soils/sediments, geomorphology of the catchment area, hydrography, pollution, biological activity of rivers, and rainwater composition. The results of this study indicate that the dominant factors influencing riverwater chemistry are the climate and the petrography of the catchment area. In the case of heavily polluted rivers, pollution appears to be the dominant factor.The approach followed is based on the watershed information, e.g., climatic, geomorphological, petrographical (percentage distribution of geochemical important petrographic units), soil/sediment composition, rainwater composition, as well as the hydrographic and the hydrochemical data of the rivers.In order to achieve a better understanding of the nature of the factors influencing river water composition as well as to specify them quantitatively, multivariate statistical analyses (factor and cluster analyses) were performed on the rain-corrected hydrochemical and petrographic information of the watersheds.     

Evaluating sampling locations in river water quality monitoring networks: application of dynamic factor analysis and discrete entropy theory

In this paper, a methodology is proposed for evaluating sampling locations in an existing river water quality monitoring network. The dynamic factor analysis is utilized to extract the independent dynamic factors from time series of water quality variables. Then, the entropy theory is applied to the independent dynamic factors to construct transinformation–distance (T–D) curves. The computation time in the case of using dynamic factors is significantly less than when the raw data is used because the number of independent dynamic factors is usually much less than the number of monitored water quality variables. In this paper, it is also shown that by clustering the study area to some homogenous zones and developing T–D curves for each zone, the accuracy of the results is significantly increased. To evaluate the applicability and efficiency of the proposed methodology, it is applied to the Karoon River which is the most important river system in Iran.     

Waste water management and water quality of river Yamuna in the megacity of Delhi

The present study aims at assessing water quality of river Yamuna in one of the world’s most polluted and populated megacities, Delhi. Conductivity, salinity and sodium content were within the permissible categories. Chloride concentration exceeded acceptable levels of drinking water guidelines. Water quality was poor at all locations with respect to heavy metal contamination, especially along the lower section of the Delhi stretch. Heavy metal concentrations were manifold higher than the acceptable limits of drinking water according to the BIS guidelines and reached ~29, 4.9, 10, 31, 27, 83, 7.3 and 27 times higher, respectively, for metals aluminum, copper, chromium, cadmium, iron, lead, manganese and nickel. The Najafgarh and the Shahdara drains are major point sources. Low oxidation–reduction potential reflected high organic loads and traces of eutrophication together with significant levels of nitrate and total phosphate. Discharges from agriculture, sewage and power plants could be important sources of high metal concentration. This calls for urgent measures to be taken for prevention of metal contamination in the river, through both, technology as well as implementation of regulations in order to sustain huge populations in megacities like Delhi. Waste water treatment from point sources needs tremendous improvement on the city. Treatment of the entire waste generated up to the tertiary level is required for minimizing dissolved solids, especially toxic metals, and rendering reuse in agriculture suitable. Treatment plants need proper operation, maintenance, uninterrupted power supply and regular monitoring. Various measure and programmes need to be undertaken to ensure safe reuse of wastewater.     

天星河、文峰河流域岩溶水化学及影响因素

重庆东北部地区巫溪天星河、文峰河的岩溶流域水化学特征研究结果表明:研究区泉水样品的p H值为6.47~8.28,平均值为7.79;流域河水饱和指数(SIc)的平均值为0.14,表明其变化受到流域碳酸盐岩分布的控制。水化学类型以HCO3-Ca型水为主,Ca2+和HCO-3平均分别占阳、阴离子的75%和82%。通过分析Gibbs图,发现泉水的主要组分属于"岩石风化类型",主要反映了岩石的溶解作用对泉水水化学的影响。流域内部分水样NO-3和SO2-4较高,可能是受工农业生产等人类活动的影响引起,此外硫酸也参与了碳酸盐矿物的溶解。     

资料缺失河道水质风险分析

资料缺失是进行水质风险分析的薄弱环节。结合水质指标浓度分布的先验信息及已有水质资料,在分析水质指标相关关系基础上建立其随时间变化的浓度分布模型,应用Bayes理论及Gibbs抽样方法对模型涉及的大量参数和超参数的统计特征进行了同步估计。在假定缺失数据为随机变量的基础上,应用该方法得到的大量样本较好实现了对缺失数据的估计,并结合风险分析理论进一步量化了水质超标风险。通过实例验证了模型的合理性,为资料缺失地区的水质风险分析提供了新的思路和方法。     

基于未确知信息的河流水质模拟预测研究

基于河水流速、污染物综合衰减系数等参量信息不确定性的特点,提出了运用未确知数学理论进行河流水质模拟预测的未确知数学模型。该模型不仅能得到以区间形式表示的河流污染物预测浓度,也能获得各浓度可能值区间对应的主观可信度,这为水污染控制系统规划和水环境管理决策提供了更为丰富、科学的浓度信息。实例研究表明,运用未确知数学理论进行河流水质模拟预测,理论上是可行的,预测结果是可靠的。     

桂江流域河流水化学特征及影响因素

2012年4月9-16日在桂江流域采集河流水样15个进行分析测试。研究结果表明:(1)桂江河水样品pH值介于6.36~8.46,平均值为7.58;EC范围为18~316μs/cm,平均值为175μs/cm;流域河水SIc平均值为-0.7,其变化受流域碳酸盐岩的分布控制。(2)桂江的水为HCO3-Ca型水,HCO3-和Ca2+平均分别占阴、阳离子的76%和77%,主要来自岩石风化。(3)中游部分河水NO3-和SO42-较高,可能是受工农业等人类活动的影响引起,此外硫酸参与了碳酸盐矿物的溶解。(4)Ca2+、Mg2+和HCO3-总体呈现中游高,上游和下游较低;SO42-和NO3-仅在中游部分受到人类活动影响较多的支流偏高,上下游相对较低且相差不大;Cl-、Na+和K+则呈现出中下游较高,上游较低的特征。      

Multivariate water quality assessment from the Tamiraparani river basin,Southern India

The hydrochemistry of a perennial river has been investigated with multivariate cluster analysis (CA) and principal component analysis/factor analysis (PCA/FA). The aim was to investigate parameters responsible for spatial and temporal variations of river water quality. Water quality was monitored along the river basin at 20 different sites over a period of 1 year from July, 2008 to June, 2009. Multivariate statistics revealed that Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃ ^?, Cl^?, H₄SiO₄, SO₄ ^2?, NO₂ ^?, and PO₄ ^3? were influenced by seasonal and spatial variations and that water quality was in the first place determined more by natural weathering processes than by anthropogenic activities. We could prove by (a) Box and Whisker plot, (b) matrix scatter score mean plot, (c) ternary plot, and (d) Gibbs plot that the chemistry of river water is controlled by lithogenic weathering processes. The higher concentration of dissolved silica during summer and the pre-monsoon season is explained by natural and tropical climatic conditions of the environment.     

Climate change outlook for water resources management in a semiarid river basin: the effect of the environmental water demand

Iran is a developing country with arid and semiarid regions. Poor management of water resources combined with the effects of climate change is leading to the drying of several rivers and wetlands. Several planned water development projects, primarily for agricultural expansion, will be implemented in the coming years which could worsen impacts on vulnerable aquatic ecosystems. Proper water resources management is essential to meet present and future residential, environmental, industrial, and agricultural demands in semiarid regions. This paper presents projections of how the availability of water resources will change in the Karkheh river basin of Iran for the period 2010–2059 employing sustainability criteria in the form of time-based reliability, volumetric reliability, resiliency, and vulnerability. This paper’s results show that consideration of environmental receptors as a stakeholder of water use places limitations on agricultural development within the Karkheh river basin.     

黄土梁峁地貌矿井水水质时空变异评估与关键控制因子水源识别

针对黄土梁峁地区砂岩-泥岩互层覆岩突水水源难以准确判别以及不同水源所占比例无法定量化问题,在系统采集了陕北朱家峁煤矿地表水、地下水水样基础上,采用数理统计、Piper三线图、Gibbs图、常规水化学特征比值法,揭示了不同含水系统水化学演化规律和水源补给关系。通过分析水体稳定同位素组成演变特征,明确了不同环境背景下各类水源水质时空变异性。在此基础上,以常规、同位素特征比因子作为判别指标,构建了基于T-球型模糊聚集算子TOPSIS法(T-TOPSIS)、粗糙集理论(RST)、D-S证据理论(DSET)与单指标未知测度函数(SIUMF)的突水水源混合比例计算模型。结果表明,研究区地表水、地下水水化学类型虽均以Na-SO4·Cl为主,但两者受控因素有着明显差别,即地表水水化学成分受硅酸盐岩风化和蒸发结晶共同控制;地下水成分则主要受控于蒸发结晶作用。此外,经历了强烈蒸发作用的地表水对地下水存在一定程度的补给作用。T-TOPSISRST-DSET-SIUMF突水水源混合比例判别模型表明,陕北朱家峁煤矿50%以上的突水水源为顶板砂岩水和地表沙空沟水。三维高密度电法探测结果验证了该模型的准确性。     

Transport of trace elements under different seasonal conditions: Effects on the quality of river water in a Mediterranean area

Concentrations of total and dissolved elements were determined in 35 water samples collected from rivers in Sardinia, a Mediterranean island in Italy. The overall composition did not change for waters sampled in both winter and summer (i.e., January at high-flow condition and June at low-flow condition), but the salinity and concentrations of the major ions increased in summer. Concentrations of elements such as Li, B, Mn, Rb, Sr, Mo, Ba and U were higher in summer with only small differences between total and dissolved (i.e., in the fraction <0.4 μm) concentrations. The fact that these elements are mostly dissolved during low flow periods appears to be related to the intensity of water–rock interaction processes that are enhanced when the contribution of rainwater to the rivers is low, that is during low-flow conditions. In contrast, the concentrations of Al and Fe were higher in winter during high flow with total concentrations significantly higher than dissolved concentrations, indicating that the total amount depends on the amount of suspended matter. In waters filtered through 0.015 μm pore-size filters, the concentrations of Al and Fe were much lower than in waters filtered through 0.4 μm pore-size filters, indicating that the dissolved fraction comprises very fine particles or colloids. Also, Co, Ni, Cu, Zn, Cd and Pb were generally higher in waters collected during the high-flow condition, with much lower concentrations in 0.015 μm pore-size filtered waters; this suggests aqueous transport via adsorption onto very fine particles. The rare earth elements (REE) and Th dissolved in the river waters display a wide range in concentrations (∑REE: 0.1–23 μg/L; Th: <0.005–0.58 μg/L). Higher REE and Th concentrations occurred at high flow. The positive correlation between ∑REE and Fe suggests that the REE are associated with very fine particles (>0.015 and <0.4 μm); the abundance of these particles in the river controls the partitioning of REE between solution and solid phases.Twenty percent of the water samples had dissolved Pb and total Hg concentrations that exceeded the Italian guidelines for drinking water (>10 μg/L Pb and >1 μg/L Hg). The highest concentrations of these heavy metals were observed at high-flow conditions and they were likely due to the weathering of mine wastes and to uncontrolled urban wastes discharged into the rivers.     

环状河网水质模型在水污染控制规划中的应用

结合一维圣维南方程及CSTR水质概念模型的机理,开发了平原环状河网非稳态水质模型,并用于温州市温瑞塘河水污染控制规划的编制中。模型由水文子模型和水质子模型两部分构成,描述了水体中COD、氨氮和DO浓度随时间、空间的动态变化。利用新开发的模型,采用试错法,估算了河网的水环境容量,并以此为基础确定了远、近期污染物排放控制目标;通过研究水质恢复的滞后性,提出可以采取引水冲污、人工曝气复氧等非常规措施来改善河网水质;并且利用情景分析方法,分别设定不同流量与不同开闸方式相组合的9种冲污情景,定量化探讨了引水冲污方案;根据曝气复氧对河网水质改善的作用特征,筛选出需要曝气复氧的重点河段和次重点河段。     

绿沸石基复合材料对河道水中氨氮去除效果研究

以绿沸石、硅藻土、膨润土、牡蛎壳为主要原材料,包衣机制粒后马弗炉焙烧制成绿沸石-硅藻土(GZD)、绿沸石-膨润土(GZB)、绿沸石-牡蛎壳(GZO)等3款球状氨氮吸附材料。探究造孔剂-粘结剂配比、物料配比、焙烧温度、焙烧时间对污水中氨氮的吸附量和材料散失率的影响,通过吸附动力学、吸附等温线、氨氮去除率、材料散失率试验探讨其吸附机理。并设计了简易装置,用实际河道水样对比分析了3款复合材料与块状绿沸石原矿对氨氮的吸附效果和重复利用次数,对处理效果最佳的GZD中的主要材料绿沸石和硅藻土进行了SEM和XRF表征。结果表明:GZD的氨氮吸附效果最佳,制备条件为造孔剂、粘结剂、绿沸石、硅藻土的质量比为1.2﹕5﹕9﹕1;在500℃下焙烧3 h;GZD对氨氮的吸附符合准二级动力学,用Freundlich等温线比Langmuir等温线更适合描述其吸附过程;GZD对实际河道水样进行5次吸附再生后仍具有明显效果。     

云南开远南洞地下河水质演变特征

在云南开远南洞地下河出口,连续19年采取旱、雨季水样进行水质变化监测,结果表明: ( 1)整体上地下水水质旱季好于雨季,历年旱季水质类型以良好为主,雨季则以较差为主; ( 2)水质变化阶段性明显: 1987— 1993年,离子浓度普遍较低,旱、雨季波动不大,水质多属Ⅰ 、Ⅱ 类,有机污染以NH+4 、NO-3 等为主; 1994—2000年,旱、雨季离子浓度均普遍升高且变化加剧, N H+4 、As、Cd、Cr、Mn出现历年最大值,金属离子污染日趋加剧,水质以Ⅱ 、Ⅲ 类为主; 2001— 2005年,旱、雨季离子浓度有升有降,以升为主, Pb、Zn、Cl- 、SO2-4 出现历年最大值,水质以Ⅱ 、Ⅲ 类为主。南洞地下河水质19年来发生了较大的变化,污染日趋严重。分析认为该地下河水质逐步变差与上游补给区盆地内经济发展状况密切相关。为此,提出了采用自动监测等方法加强地下河动态变化监测研究以及实行分区、分级管理等水质保护的具体对策建议。      

Evaluation of the effect of water management interventions on water level of Gaza coastal aquifer

Gaza coastal aquifer (GCA) is the most precious natural source where it is the only source of water for different uses. Groundwater crisis in Gaza includes two major folds: shortage of water supply and contamination. The extraction of groundwater currently exceeds the aquifer recharge rate. As a result, the groundwater level is falling continuously leading severely deterioration of GCA. The main objective of this study is to analyze and evaluate the current and proposed water resources management plans and their effect on the water level of GCA. In this respect, the available quantities of rainfall that could be harvested and infiltrated from different types of land-use based on existing and planned situations are studied using GIS tool and numerical models for GCA using V-MODFLOW environment for simulating four scenarios: (i) existing management practice (no action scenario), (ii) proposed Palestinian Water Authority (PWA) stormwater infiltration plan, (iii) proposed Gaza Emergency Technical Assistance Program (GETAP) interventions, and (iv) combination between second and third scenarios. The management scenarios were tested with the calibrated flow model for the target period between 2016 and 2040. The simulation results of existing management practice scenario show that there are several depression zones in Gaza Strip; in southern part from ??18 to ??24 m MSL in 2020 and 2040, in the northern part from ??7 to ??12 m MSL in 2020 and 2040, and in the middle regions experienced a small decline in groundwater level. The simulation results of proposed PWA scenario indicate similar depression zones as per first scenario but with good enhancement of water level, ??17 to ??18 m MSL in the southern part and ??3 to ??6 m MSL in the northern part in 2020 and 2040, respectively. The simulation results of GETAP intervention scenario show a positive impact on groundwater level. The results of fourth scenario show good enhancement of water level, in which the water level in the northern part ranges from +?3 to +?6 m MSL in 2020 and 2040, while in the south part ranges from ??15 to +?4 MSL in 2020 and 2040.     

丹江口水库库区及周边地区河网形态、地貌特征及构造活动性意义

河流作为构造-气候相互作用最为敏感的地貌单元,记录了丰富的水系演化、构造变形以及气候变化等信息。通过研究河流的形成与演化过程来阐述区域地貌和构造活动特征是构造地貌研究的一个突破点,河流形态的空间变化是阐述河流形成与演化特征最为直观有效的方法。丹江口水库库区地貌特征复杂、地质灾害频发、差异性构造活动较为强烈,是开展构造地貌研究的理想场所。通过对丹江口水库库区及周边地区河流形态特征、地貌特征及构造活动特征等进行综合分析发现,河网分维值空间特征与区域内构造活动性较强的断裂的空间分布高度吻合,构造活动性较强的断裂带及周边地区,河网受到构造活动的影响,发育不成熟,河网分维值出现低值,分维值均小于1.115;构造活动性较弱的断裂带及周边地区,河网发育过程中未受到构造活动的影响,发育较成熟,河网分维值高,分维值均大于1.25;而河网分维值空间变化与地形坡度、平均高程等地貌参数相关性不显著。因此,区域构造活动性特征是河网形态空间变化控制的关键因素。利用河网形态的分维特征量化区域构造活动的强弱及各区域构造活动的差异,对于河流的形成与演化、构造活动性及预测地质灾害的发生等方面的研究都有一定的参考价值。