沈阳地区地下水污染特征及应用灰色系统理论进行水质预测的研究

沈阳地区地下水水质污染逐年趋向恶化。本文在阐明区域环境条件、地下水污染特征及地下水质进行评价的基础上，应用灰色系统理论，建立了我国第一个大型集中供水城市地下水常量组份的灰色预测模型，并应用模型对该区地下水水质进行了详细的预测研究。由于在模型中引用了溶液理论，建立了水化学平衡控制模型，使预测结果的可信程度大为提高。     

水文地球化学模拟研究的现状

水文地球化学模拟是研究地质生态，地下水污染的一种新的方法，是多学科综合研究的产物，通过各种不同的水文地球化学模型，可以定量模拟各种自然过程和人类活动影响下水－岩相互作用及地下水中污染质的运移过程，预测地下水污染的发生，发展趋势，指导地地下水的监测，保护及合理开采，是地下水管理中不可缺少的一部分。综述了有关水文地球化学模拟研究的现状，对水溶液组分平衡的地球化学模型，地下水溶质运移模型，耦合水化学模型     

地下水质模型在人工回灌中的应用

随着水文地质工作的不断深入和计算技术的发展,在地下水质研究方面,已由定性研究发展到定量研究,开始应用地下水质模型解决实际问题。地下水质模型是应用数学模型研究地下水中可溶物质弥散迁移时,浓度的时空变化规律,预测被污染地下水的瞬时状态与扩展范围,对污染物质在地下水中的迁移作出定量评价,为制定合理有效的防治污染措施提供科学依据。近年来,世界上一些发达国家已开展了地下水质模拟研究,建立了若干相应的水质模型。我国从1980     

地下水污染趋势预测研究

在水量平衡及物料平衡的基础上,利用概念性模型,预测了山西省大同市近几十年的地下水污染情况,并结合模型结果,讨论了地下水恶化的主要原因是地下水超采形成降落漏斗、污水灌溉,以及有些地区不允许已使用过的地下水出境等。本文的研究可为地下水水质保护工作提供科学依据。     

西宁市贵德县河滨公园林场第四系含水层弥散试验研究

地下水污染问题日益严重,研究溶质运移的弥散理论开始应用于实际问题。建立地下水溶质运移模型,对地下水中污染物的运移及发展趋势进行准确预测,是对地下水进行保护、对地下水污染进行控制的基础。而弥散参数的确定则是地下水溶质运移模型建立的关键环节之一,直接影响着模型预测结果的精度和准确性。 对西宁市贵德县地下水污染的水质运移规律进行分析,在贵德县河滨公园林场采用径向收敛流水动力弥散理论方法进行了第四系含水层现场弥散试验,计算了试验场地潜水含水层的弥散度,获得纵向弥散度(a_L)为0.843~0.998 cm,横向弥散度(a_T)经验推断值为0.17~0.20 cm,为进一步建立该地区的地下水溶质运移模型、预测地下水污染的发展趋势和评价该地区地下水环境质量提供了数据参考。     

基于解析法的地下水环境质量评价研究——以国粤韶关燃煤电厂灰场为例

地下水污染防治是当前环境污染防治中的重点课题之一,进行地下水环境质量评价是解决地下水污染防治问题的重要途径之一。采用解析法,选取灰渣溶滤后产生的SO_4~(2-)和F~-作为污染因子,预测在事故工况条件下污染物的运移过程及影响范围。结果显示,解析法的模型可靠、预测结果合理实用,为建设燃煤电厂灰场后可能引起的地下水污染提供科学的预测手段。     

化工区地下水污染预测研究与评价方法探讨

本文介绍了运用溶质迁移模型预测化工区地下水质污染和用统计模型预测化工区区域井水污染,为制定一个防治地下水污染的整体规划提出了科学依据,对控制现有的污染程度和范围有重要的意义。     

岩溶地下水集中开采区水质系统预测研究

在岩溶地区，地下水的超强度开采与工业“三废”及生活废弃物不合理的排放，造成了地下水较严重的污染。用动态系统方法建立的地下水污染时间序列递推预测模型，在岩溶地下水环境质量预测与管理方面都具有指导意义。     

地下水不的自组织预测模型及其应用

自组织预测模型是前苏联学者Ｉｖａｋｈｎｅｎｋｏ于７０年代提出的一种非线性建模预测方法,它能有效地解决复杂非线性系统的数据处理和建模问题,应用自组织方法进行地下水污染预测,以实际监测数据为基础,建立了地下不不污染预测的自组织模型,其预测精度较高,检验误差在５．２％以内。     

灰色水文地球化学预测模型(GHGCM)——以沈阳市潜水为例

建立多组分平衡化学模型研究溶质在地下水中的迁移是溶液理论的基本要求,这是非确定型模型预测地下水溶质迁移中尚未解决的课题.本文利用CM(1.1)模型同时预测水中全部化学组分浓度值约束于电中性定律和最大溶度积理论,求得预测优化值,为这一问题的解决提供了范例.模型运行的结果证明,灰色系统理论不仅可用于预测水中单个离子,也可预报平衡多组分.     

辽西地区地下水水质污染评价及趋势分析

依据辽宁西部的锦州、阜新、盘锦、朝阳、葫芦岛地区2006-2010年间地下水水质检测结果,采用地下水水质综合污染指数评价方法,与污染起始值相比较,认为超过污染起始值即为受到了污染。辽西地区地下水水质污染评价结果表明,地下水未污染范围逐年增加,大部分水质点处于极轻微污染—中度污染状态,重度—严重污染的水质点逐年变化不大且略有减少。地下水水质综合变化趋势分析结果表明,辽西地区各年均以地下水水质稳定占主导趋势,地下水水质变差趋势明显减弱,地下水水质总体趋于稳定,并且地下水水质逐年向好的方向转化。     

区域地下水污染综合评价研究现状与建议

区域地下水污染综合评价研究是一项总结区域地下水水质特征、评估地下水水质和污染状况、分析其驱动机制、研判其演化趋势的重要基础性工作,也是地下水污染防控以及水质改善的重要依据。受水文地质领域一些传统概念、观念以及技术方法的限制,在水质综合评价、污染评价、天然劣质水与污染的区分、人类活动影响等方面存在诸多问题和挑战,认知的科学性和可靠性不断受到质疑,给政府管理部门的应用和决策带来困惑。本研究通过梳理分析近年来区域地下水污染综合评价的研究现状,回顾总结了在水质综合评价、背景值、污染评价、劣质水和劣变水评估以及人类活动识别等方面存在的问题,提出了几点认识和建议:(1)“指标分类评价-组合表达”的水质及污染综合评价思路,可为解决现阶段水质及污染综合评估容易造成歧义和误导的问题提供新的方向;(2)视背景值的建立不仅能够解决传统概念背景值无法获取的问题,还能有效进行污染判定、劣质水和劣变水评估以及人类活动识别,是一项亟待全面开展的基础性工作;(3)劣质水和劣变水概念及评价思路的提出,对区分天然劣质水和污染水具有借鉴意义,在科学回答这两类水对我国地下水水质的影响、帮助决策者理解水质不安全成因等方面有重要意义,但是方法学方面需要进一步探讨;(4)对人类活动影响的识别和量化,进一步推动了对输入型污染、诱导型水质恶化以及水化学场变化所引起的各种水质问题的认识,进而对判断水质演化趋势、污染防控、分类解决水质问题具有重要的意义。     

松嫩盆地的地下水化学特征及水质变化规律

松嫩盆地位于东北腹部, 是我国主要的大型地下水盆地之一.地下水资源十分丰富, 但水质问题复杂, 原生水质状况不佳, 人为污染比较严重.根据水利、地质部门多年积累的地下水水质监测资料, 对地下水中原生有害组分和人为污染组分的形成机理和区域分布规律进行了比较全面、深入的研究, 着重分析了在人为活动影响下, 盆地不同地下水系统内地下水水质的多年变化规律.认为地质构造上的封闭性、强还原/弱碱性/富含有机质的水文地球化学环境、地下水运动滞缓是盆地地下水中多种原生有害组分富集的基本条件.近半个世纪以来强烈的人类活动, 则是导致地下水水质发生趋势性变化的主要原因.提出了改善区域地下水交替循环条件, 治理环境污染, 治理和更新已成为污染通道的水井, 利用洁净松花江水开展地下水人工回灌等改良与保护地下水水质的主要措施.      

Modeling of groundwater draft based on satellite-derived crop acreage estimation over an arid region of northwest India

Over-exploitation of groundwater for agricultural crops puts stress on the sustainability of natural resources in the arid region of Rajasthan state, India. Hydrogeological study of groundwater levels of the study area during the pre-monsoon (May to June), post-monsoon (October to November) and post-irrigation (February to March) seasons of 2004–2005 to 2011–2012 shows a steady decline of groundwater levels at the rate of 1.28–1.68 m/year, mainly due to excessive groundwater draft for irrigation. Due to the low density of the groundwater observation-well network in the study area, assessment of groundwater draft, and thus groundwater resource management, becomes a difficult task. To overcome the situation, a linear groundwater draft model (LGDM) has been developed based on the empirical relationship between satellite-derived crop acreage and the observed groundwater draft for the year 2003–2004. The model has been validated for a decade, during three year-long intervals (2005–2006, 2008–2009 and 2011–2012) using groundwater draft, estimated through a discharge factor method. Further, the estimated draft was validated through observed pumping data from random sampled villages (2011–2012). The results suggest that the developed LGDM model provides a good alternative to the estimation of groundwater draft based on satellite-based crop area in the absence of groundwater observation wells in arid regions of northwest India.     

Intrinsic groundwater vulnerability determination at the aquifer scale: a methodology coupling travel time estimation and rating methods

Groundwater vulnerability has been subject of much research due to the valuable information it provides concerning groundwater protection and exploitation potential. Up to now, most groundwater vulnerability studies adopt subjective systems of rating the various factors and subsequently, their results are often ambiguous and contradicting. Within the present study a methodology for the estimation of intrinsic groundwater vulnerability at the aquifer scale is presented. The methodology is based on travel time estimation from specified sources of pollution to the aquifer. Besides the deterministic calculation of travel times, the methodology provides a rating system for each pollution source, based on its relative severity and the estimated threat that it poses to the aquifer. Therefore, it can be regarded as a hybrid method that couples the advantages provided by the physically based methods with those of the subjective rating systems. The methodology is applied to the Neon Sidirochorion aquifer, Northeastern Greece, an overexploited aquifer where river waters, sea waters and lake waters interact, causing groundwater quality deterioration to the aquifer. The results indicated that the proposed groundwater vulnerability assessment methodology is well capturing pollution related to saltwater intrusion and agricultural activities, while it is concluded that the conceptual model is significantly affecting the vulnerability assessment results and therefore has to be previously developed.     

Evaluation of groundwater quality and pollution in Daqing Oilfield

Daqing Oilfield is located in the northeast of Songnen Plain in Daqing City, Heilongjiang Province, which is a petrochemical industry gathering place based on petroleum refining, chemical industry, chemical fiber and fertilizer. In recent years, the quantity demand of petroleum and petrochemical production for groundwater in Daqing Oilfield is growing, and it’s of great significance to analyze and study the quality and pollution degree of groundwater for groundwater exploitation, utilization and protection. In this paper, groundwater quality of Daqing Oilfield evaluated by Nemerow Index is poor, and most points are Class IV groundwater; When evaluating groundwater pollution by hierarchical ladder method, the results show that the severe and extremely severe pollution points account for 34.48% in shallow phreatic water and 20% in deep confined water, showing that shallow groundwater is more seriously polluted than the deep. The main components influencing the quality of groundwater in the study area are total hardness, total dissolved solids, Cl-, SO42- and so on, which are affected by both the native environment and human activities; The main pollution components in groundwater are nitrite and nitrate nitrogen which are affected by human activities. Daqing Oilfield groundwater pollution is characterized by inorganic pollution, while organic components related to human activities contribute less to the groundwater pollution currently.     

RETRACTED ARTICLE: Development prospects of groundwater resources in an elliptical shape island,Union Territory of Lakshadweep,India

A major problem of the islanders is the availability of fresh water for drinking purpose. Groundwater is the only source of fresh water for the islanders. The demand for groundwater is increasing very year due to growing population and urbanization. A proper understanding of the groundwater condition is important in order to meet this increasing demand and to formulate future development and management strategies. It is in this context, principal hydrogeologic units; water table fluctuation pattern, general groundwater potential, existing groundwater withdrawal structures and draft, water quality, etc. have been studied in an elliptical shape Andrott Island of Union Territory of Lakshadweep, India, through field investigation and secondary data collection. Groundwater occurs under phreatic condition and seawater is in hydraulic continuity with the groundwater as evidenced by the tidal influence in almost all the wells. Groundwater level fluctuation due to seasonal variation varies from 0 to 0.542 m depending on the distance of the well from the coast. Depth to groundwater level varies from less than 1.234 to 3.520 m depending on the topography. Groundwater level fluctuation is due to the combination of factors like rainfall, tidal activities, sub-surface runoff, and draft. Large diameter dug wells are the main groundwater extraction structures in this island. There are 2,143 dug wells with almost each family having its own well and the density of the dug wells is about 437/km². The stage of groundwater development is estimated as 37% and hence “Safe” for further groundwater development in this island. However, considering the very limited fresh-water resources and also the growing demand for groundwater, various management strategies such as rainwater harvesting, artificial recharge of groundwater, public participation in water conservation and wise use of groundwater, etc., have been suggested.     

The role of hydrogeology in solution-subsidence development and its environmental impacts; a case-study for Sazlıca (Niğde, Turkey)

Solution-subsidence and other types of collapse failures developed in the vicinity of Sazlıca have been a major source of environmental problems such as groundwater pollution, soil erosion, and foundation failures. Extensive pumping of water from the Lake Dipsiz during irrigation seasons creates landslide developments at the shores of the lake. Five stages of landslide development were observed in the unconsolidated soils around Lake Dipsiz. Bowl-shaped solution-subsidence features with depths from 1 to 3 m and diameters between 1 and 60 m were formed due to excess pumping, and recharge and discharge features of unconfined aquifer. The pumping activities must be controlled to prevent further environmental problems. Lake Dipsiz and other subsidence developments are the groundwater exposure areas highly vulnerable to contamination. The proposed remedies for overcoming the environmental problems are the establishment of conservation areas around such natural features; ceasing the removal of top soil, controlling the urbanization, and keeping the livestock farming away from the areas susceptible to pollution. Received: 2 June 1997 · Accepted: 16 January 1998     

Regional distribution pattern of groundwater heavy metals resulting from agricultural activities

Contaminations of groundwater by heavy metals due to agricultural activities are growing recently. The objective of this study was to evaluate and map regional patterns of heavy metals (Cd, Zn and Cu) in groundwater on a plain with high agricultural activities. The study was conducted to investigate the concentration of heavy metals and distribution in groundwater in regions of Shush Danial and Andimeshk aquifers in the southern part of Iran. Presently, groundwater is the only appropriate and widely used source of drinking water for rural and urban communities in this region. The region covers an area of 1,100 km² between the Dez and Karkhe rivers, which lead to the Persian Gulf. For this study, the region was divided into four sub-regions A, B, C and D. Additionally, 168 groundwater samples were collected from 42 water wells during the earlier months of 2004. The flame atomic absorption spectrometry (AAS-Flame) was used to measure the concentration of heavy metals in water samples and the Surfer software was used for determination of the contour map of metal distribution. The results demonstrated that in all of the samples, Cd and Zn concentrations were below the EPA MCLG and EPA secondary standard, respectively. However, the Cu contents of 4.8 % of all samples were higher than EPA MCL. It is also indicated that the concentrations of metals were more pronounced at the southern part of the studied region than at the others. The analysis of fertilizers applied for agricultural activities at this region also indicated that a great majority of the above-mentioned heavy metals were discharged into the environment. Absence of confining layers, proximity to land surface, excess agricultural activities in the southern part and groundwater flow direction that is generally from the north to the southern parts in this area make the southern region of the Shush plain especially vulnerable to pollution by heavy metals than by other contaminants.