Groundwater Quantity Research Articles

MALDI-TOF MS for the Identification of Cultivable Organic-Degrading Bacteria in Contaminated Groundwater near Unconventional Natural Gas Extraction Sites.

Groundwater quality and quantity is of extreme importance as it is a source of drinking water in the United States. One major concern has emerged due to the possible contamination of groundwater from unconventional oil and natural gas extraction activities. Recent studies have been performed to understand if these activities are causing groundwater contamination, particularly with respect to exogenous hydrocarbons and volatile organic compounds. The impact of contaminants on microbial ecology is an area to be explored as alternatives for water treatment are necessary. In this work, we identified cultivable organic-degrading bacteria in groundwater in close proximity to unconventional natural gas extraction. Pseudomonas stutzeri and Acinetobacter haemolyticus were identified using matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF MS), which proved to be a simple, fast, and reliable method. Additionally, the potential use of the identified bacteria in water and/or wastewater bioremediation was studied by determining the ability of these microorganisms to degrade toluene and chloroform. In fact, these bacteria can be potentially applied for in situ bioremediation of contaminated water and wastewater treatment, as they were able to degrade both compounds.

Dampak Ekonomi dan Lingkungan Ekspansi Perkebunan Kelapa Sawit (Studi Kasus: Desa Penyabungan, Kecamatan Merlung, Kabupaten Tanjung Jabung Barat, Jambi)

Oil palm is one of the major plantation commodity that earns foreign exchange. The expansion of oil palm plantation potentially gives not only economic benefits, but also the environmental problems. Therefore, the economic and environmental impacts of oil palm plantation expansion need to be assessed. This study uses revenue analysis to estimate the economic benefits, descriptive analysis to identify environmental impacts, and to estimate external costs using replacement cost and cost of illness. In this research, expansion is defined as the conversion of a part of or whole rubber plantation to oil palm plantation. The expansion resulted in farmers turning some or all of rubber gardens into palm oil plantations that resulted in an increase in revenues of 40.52%. In addition to the on-farm sector, farmers benefit from off-farm (24.46%) and non-farm (25.61%), bringing the total increase of farmers' income by 33.42%. Based on community perceptions of environmental impacts due to oil palm plantation expansion in the form of reduced quantity of groundwater, water pollution, and decreased animal population. The environmental impact of crude palm oil (CPO) factories is to produce liquid waste from palm oil processing that raises external costs for the community in the form of the replacement cost of clean water and the cost of illness

STAND-ALONE EDUCATIONAL CENTER

The world is suffering from the worse refugee crises since World War II as Syria alone has 7.6 million. Out of which 85,000 people (December 2015) are living at Al Zaatari camp located in Jordan near to Jerusalem. A need to design and build a sustainable self-sufficient educational center for the school children was felt. A district wise study and site analysis was performed using geographical information and climate analysis computer tool, Climate Consultant 6.0 to figure out important factors like quantity of ground water, rainfall intensity, solar radiation and sun path at the site. Integrating different sustainable active and passive strategies for energy generation developed building plan. The model was simulated using annual whole building energy modeling software (Safeira â„¢), Photovoltaics can produce 50% of the required energy, natural ventilation and geothermal heat pump can reduce the annual energy consumption by 9.28% and 2% respectively, if used in months in which they are more useful whereas the remaining energy can be covered by wind turbines. With skylights, enough daylight was provided (unlit areas were reduced to 10%) and providing natural ventilation as well. It was concluded that a Stand-Alone refugee center for Syrian refugees at Al Zatari camp is possible and could well be constructed if proper support from international community is provided.

Assessment of groundwater quality and its suitability for agricultural uses in Kifri

Groundwater is regarded as one of the main water sources in a number ofcountries in the world to supply cities and urban areas with water for domestic,agricultural and industrial uses. That is because of lack of surface water andrainfall quantities. Therefore, the levels and quantities of groundwater should beobserved regularly. The quality of groundwater is mainly influenced by theeffects of anthropogenic sources. The aim of this study is to evaluate the qualityof groundwater in Kifri district. In this case fifteen groundwater samples werecollected at identical locations from deeper wells in order to investigate theirquality parameters such as: pH, Electric conductivity, total dissolved solids,concentration of soluble ions and some others. The results of the concentrationswere measured and interpreted with some irrigation indexes such as sodiumpercent (SP), sodium adsorption ratio (SAR), residual sodium carbonate (RSC),magnesium hazard (MH%), and Kelly’s ratio (KR).The results reveal that all of groundwater samples have SAR less than(10); it is indicating water class to be of excellent quality. Also, all the sampleshave RSC less than the permissible (1.5). However, it is observed that (6.67 %)of the samples have MH ratio values greater than (50). Presence of moremagnesium in irrigation water compared to calcium leads to increase the degreeof magnesium saturation thus decrease soil productivity. The results also revealthat the samples have values of (SP) less than (60%). Overall, it indicates thatthe quality of (93.33%) of the samples falling under excellent category forirrigation purposes.

Percolation pond as a method of managed aquifer recharge in a coastal saline aquifer: A case study on the criteria for site selection and its impacts

Percolation ponds have become very popular methods of managed aquifer recharge due to their low cost, ease of construction and the participation and assistance of community. The objective of this study is to assess the feasibility of a percolation pond in a saline aquifer, north of Chennai, Tamil Nadu, India, to improve the storage and quality of groundwater. Electrical resistivity and ground penetrating radar methods were used to understand the subsurface conditions of the area. From these investigations, a suitable location was chosen and a percolation pond was constructed. The quality and quantity of groundwater of the nearby area has improved due to the recharge from the pond. This study indicated that a simple excavation without providing support for the slope and paving of the bunds helped to improve the groundwater quality. This method can be easily adoptable by farmers who can have a small pond within their farm to collect and store the rainwater. The cost of water recharged from this pond works out to be about 0.225 Re/l. Cleaning the pond by scrapping the accumulated sediments needs to be done once a year. Due to the small dimension and high saline groundwater, considerable improvement in quality at greater depths could not be achieved. However, ponds of larger size with recharge shafts can directly recharge the aquifer and help to improve the quality of water at greater depths.

خصائص المياه الجوفية في الجزء الشمالي من قطر ، الدراسات الهيدرولوجية والمائية الكيميائية ، الاستخدامات والقضايا ، قطر

الملخص: بما أن المياه الجوفية هي المصدر الوحيد للمياه ، فإن هناك حاجة ماسة لاستكشاف طبقة المياه الجوفية إلى جانب استيراد المياه من الدول المجاورة وفرض ضغوط خدمة على موارد المياه الجوفية المتاحة. يتناول العمل الحالي الجيولوجيا المائية ، والجيوفيزياء المائية ، والكيمياء المائية ، وإدارة المياه الجوفية والتخطيط في شبه جزيرة قطر. ولهذا الغرض ، تم إجراء رحلات ميدانية لقياس الخصائص الجيوكهربائية للوحدات الصخرية التي تتكون منها التتابعات الجيولوجية ، وكذلك قياس عمق المياه وخصم منسوب المياه الجوفية للآبار المختارة والاختبارية للاستفادة من طبقات المياه الجوفية المثبتة بالفعل (خزانات المياه الجوفية بالدمام ، والروس ، وأم الرضومة). بالإضافة إلى ذلك ، تم جمع عينات المياه الجوفية من الآبار المختارة للتحليل الكيميائي. تم تضمين وصف موجز لجيولوجيا قطر في هذا العمل مع إيلاء اهتمام خاص لعلم الصخر للتكوينات الحاملة للمياه ، وتأثير الهيكل على الظروف الهيدروجيولوجية. تمت دراسة الظروف الجيولوجية تحت السطحية لشبه جزيرة قطر من خلال تفسير بيانات المسح الجيوكهربائي. تم إجراء 19 سبر كهربائي رأسي (VESes) في منطقة الدراسة. ارتبطت القياسات الجيوكهربائية المفسرة بالمعلومات المتوفرة عن بعض الآبار. تعتمد دراسة الظروف المائية الكيميائية لطبقات المياه الجوفية في قطر بشكل أساسي على التحليل الكيميائي لعينات المياه التي جمعها المؤلف الحالي. تم تحديد إجمالي المواد الصلبة الذائبة (TDS) ، الكاتيونات الرئيسية ، الأنيونات الرئيسية (Na + ، Cl- ، Ca + 2 ، SO4-2 ، Mg + 2 ، CO3-2 ، HCO3-) و PH. بالإضافة إلى ذلك ، تم حساب المعاملات المائية الكيميائية لتحديد أصل المياه الجوفية ومدى ملاءمة المياه الجوفية لأغراض الري. تهدف الدراسة الحالية إلى: التعرف على الظروف الجيولوجية تحت السطحية اللازمة لتوضيح الظروف الهيدروجيولوجية لشبه جزيرة قطر. ودراسة الظروف الهيدروجيولوجية الجماعية لشبه جزيرة قطر في ضوء البيانات الجديدة والمعلومات التفصيلية التي تتيح إمكانية وجود موارد مائية جوفية إضافية واقتراح خريطة هيدروجيولوجية لدولة قطر. وتخطيط موارد المياه الجوفية بهدف تعظيم الاستفادة من المياه الجوفية في ضوء كمية ونوعية المياه الجوفية. تعرض دراسة بعض المناطق في شمال دولة قطر نتائج التحليل الجيوكيميائي للمياه في طبقات المياه الجوفية ، والتغير في منسوب المياه الجوفية وملوحة الآبار. بناءً على عينات من المياه تتراوح بين 1500-12000 جزء في المليون في الملوحة (TDS) ، يتراوح منسوب المياه الجوفية بعمق 35-200 متر. تقدم هذه الدراسة أفضل طريقة مفيدة لاستخدامها في عدة مجالات وفقًا للعديد من العوامل. الأنيونات الرئيسية والكاتيونات هي مؤشرات مفيدة للجيوكيميائية وتوافر المياه في طبقات المياه الجوفية ، وتتراوح الوحدات المناسبة لمياه الري والاستخدامات البشرية بين 1000-5000 جزء في المليون ، وهذا تأثير المشكلة على الاستخدامات السطحية. توضح الدراسة الجيولوجية الطبقات الصخرية التي تحتوي على الماء وتكوينها وسمكها وتركيبها. حوالي ثلاثة خزانات مياه جوفية رئيسية في قطر (طبقة المياه الجوفية بأم رداهما باليوسين ، خزان تكوين روس الأيوسين ، خزان تكوين الدمام الإيوسيني). تدعم طرق الجيوفيزياء الدراسات الجيولوجية للحصول على معلومات مفصلة حول منسوب المياه الجوفية وتمديد الخزان الجوفي. يلعب علم الصخور وتركيب طبقة المياه الجوفية في قطر دورًا مهمًا في الاحتفاظ بالمياه بين الطبقات. تعتبر النتائج الرئيسية للعينة الجيوكيميائية للمياه ورسم خرائط المياه الجوفية بين طبقات المياه الجوفية مهمة في تفسير البيانات من الخزان الجوفي ، والتي تعمل على تذكيرنا بالاستخدامات المختلفة للمياه الجوفية.

A spatiotemporal Bayesian maximum entropy-based methodology for dealing with sparse data in revising groundwater quality monitoring networks: the Tehran region experience

Data inadequacy is a common problem in designing or updating groundwater monitoring systems. The developed methodologies for the optimal design of groundwater monitoring systems usually assume that there is a complete set of data obtained from existing monitoring wells and provide a revised configuration for the system by analyzing the current data. These methodologies are not usually applicable when the current groundwater quantity and quality data are highly sparse. In this paper, a new simulation–optimization approach based on Bayesian maximum entropy theory (BME) is proposed for revising spatial and temporal monitoring frequencies in a sparsely monitored aquifer. The BME is used to simulate the spatial and spatiotemporal variations of groundwater indicators, incorporating the space/time uncertainties due to insufficient data. Comparing the obtained estimations with observations, the best BME model was selected to be linked with an optimization model. The main goal of optimization was to find out the spatial and temporal sampling characteristics of the monitoring stations using the concepts of Entropy theory and a groundwater vulnerability index. The results show the BME estimations are less biased and more accurate than Ordinary Kriging in both spatial and spatiotemporal analysis. The improvements in the BME estimates are mostly related to incorporating hard (accurate) and soft (uncertain) data in the estimation process. The applicability and efficiency of the proposed methodology have been evaluated by applying it to the Tehran aquifer in Iran which is suffering from high groundwater table fluctuations and nitrate pollution. Based on the results, in addition to the existing monitoring wells, seven new monitoring stations have been proposed. Few stations which potentially can be removed or combined with other stations have been identified and a monthly sampling frequency has been suggested.

THE IMPACT ON ENVIRONMENT OF ACCOMMODATION ESTABLISHMENTS AND DEVELOPMENT OF ECO-HOTELS AS AN INNOVATIVE CONCEPT OF HOSPITALITY

Environmental impact of touristic infrastructure accommodation facilities is quite significant as the activities of such institutions often involve excessive consumption of natural resources, fresh water in particular, and water pollution due to lack of advanced wastewater treatment systems, production of large quantities of solid waste. The concentration of a large number of such facilities in areas with high recreational value can lead to deterioration of the aesthetic value of the landscape. Therefore the purpose of our research is to analyze the negative impact of touristic infrastructure accommodation facilities especially, powerful hotel and restaurant and entertainment complexes on the environment. In the study we have revealed that worsening of the problems associated with the development of the hospitality industry was the impetus for the development of eco-hotels. The paper reviews the problems and prospects of development of eco-hotels in Ukraine which is a promising direction, because the country has a large number of areas suitable for the development of eco-hotels, a relatively low level of industrialization territory the increase in investment from abroad in the hotel industry. The authors have also defined that the main environmental impacts of accommodation facilities of tourist infrastructure is primary landscape changes, changes in quantity and quality of groundwater, air pollution due to the impact of transport infrastructure and environmental pollution waste within the tourist destinations. The research results allow reasonable approach to the construction of accommodation facilities of tourist infrastructure and reduce the negative impact on the environment.

Perceptions of groundwater degradation and mitigation responses in the Haouaria region in Tunisia

Avoiding the negative effects of intensive groundwater resource use is challenging, especially when the interactions and causal pathways between biophysical and socioeconomic processes are complex, and when users, management, and regulatory bodies are spatially dispersed. The plain of Haouaria, in north-eastern Tunisia, has witnessed an important development of groundwater abstraction, fueled by the multiplication of wells tapping the underlying shallow and deep aquifers. As the economic activities linked to such development are threatened by the degradation of groundwater quantity and quality, the aim of this paper is to investigate actors’ perceptions of these processes and to emphasize the undertaken mitigation measures. The study builds on semi-directive surveys with the different groundwater users and archive data in order to understand the technical, institutional and agricultural practices driving groundwater development. The paper starts by investigating the historical context of groundwater development and the progressive degradation of the resource. Then, the paper identifies the main constraints and adaptation strategies of the various users (public and private), before examining the challenges faced by groundwater users. Results show varied patterns of actors' behavior, interest, and perception of the groundwater resource. This analysis show that farmers' lack of collective action, land tenure insecurity, labor shortage, the monopoly of production inputs by suppliers, and the cost of energy for pumping are the main challenges faced by groundwater users. The study finally explores different management and policy options that can lead to a more environmentally and socioeconomically sustainable socio-hydrological system.

The peri-urban to urban groundwater transfer and its societal implications in Chennai, south India – A case study

The aquifer of the peri-urban/rural areas of Chennai Metropolitan Area in Tamil Nadu acts as a source of informal water market, and a huge amount of water is transferred and marketed by entrepreneurs, such as private water suppliers and packaged water industries. Water transfer from agricultural to non agricultural uses is not only common in India but most of the water starved developing countries experience it. It leads to temporal and spatial changes in the groundwater quantity and quality, and generates the inequity and affordability issues in accessing the water especially to the peri-urban poor. The paper analyzed the above issue with a case study conducted at Perumbakkam, a Chennai peri-urban village. The multivariate statistical analysis of field findings has been conducted in the peri-urban village for understanding the socio-economic implications of the groundwater market. The study identifies the major findings due to the prevailing informal groundwater market and emphasizes the institutional mechanism through regulatory and legal measures to protect the resource base and conservation and restoration mechanism to replenish the depleting resources.

Anthropization of groundwater resources in the Mediterranean region: processes and challenges

A comprehensive overview is provided of processes and challenges related to Mediterranean groundwater resources and associated changes in recent decades. While most studies are focused thematically and/or geographically, this paper addresses different stages of groundwater exploitation in the region and their consequences. Examples emphasize the complex interactions between the physical and social dimensions of uses and evolution of groundwater. In natural conditions, Mediterranean groundwater resources represent a wide range of hydrogeological contexts, recharge conditions and rates of exploitation. They have been actively exploited for millennia but their pseudo-natural regimes have been considerably modified in the last 50 years, especially to satisfy agricultural demand (80% of total water consumption in North Africa), as well as for tourism and coastal cities. Climate variability affects groundwater dynamics but the various forms of anthropization are more important drivers of hydrological change, including changes in land use and vegetation, hydraulic works, and intense pumpings. These changes affect both the quantity and quality of groundwater at different scales, and modify the nature of hydrogeological processes, their location, timing, and intensity. The frequent cases of drastic overexploitation illustrate the fragility of Mediterranean groundwater resources and the limits of present forms of management. There is no easy way to maintain or recover sustainability, which is often threatened by short-term interests. To achieve this goal, a significant improvement in hydrogeological knowledge and closer collaboration between the various disciplines of water sciences are indispensable.

Lateral groundwater flow and pond interactions during dry and wet years

Groundwater and surface water are tightly coupled elements of the hydrologic cycle that have often been treated as separate entities. Future climate change modelling has predicted that hydrologic cycle changes, namely increasing drought frequency and flood-type events, are likely to occur. These events may directly impact the quality and quantity of both groundwater and surface water. Future water management policies must therefore be based on an understanding of how interactions between groundwater and surface water will change with a warming climate. The aim of this study was to model and analyze the lateral flow of groundwater and its interactions with a nearby pond in a shallow, unconsolidated, unconfined aquifer. Data were collected as part of a larger and ongoing study during the year 2012, a comparatively dry year, and 2013, a comparatively wet year. We first used ArcGIS and Visual MODFLOW Flex to create a conceptual model of the system, its soil layers, monitoring wells, and potential flow patterns. We then analyzed hydraulic head data, and calculated groundwater flow volumes using the Dupuit equation. We found that the groundwater flow direction reversed in the summer of 2012 and continued until the spring of 2013. Additonally, flow rate was greater in 2013 than 2012. The flow reversal was likely caused by higher evaporative demand during the summer months of 2012, drawing substantially more water from the pond than from the soil. The two-year timeframe was not long enough to determine whether this was a typical, yearly pattern, or was primarily due to the fact that 2012 was a particularly dry year.

Analyzing the hydrological impact of afforestation and tree species in two catchments with contrasting soil properties using the spatially distributed model MIKE SHE SWET

Groundwater depletion occurs at a global scale but requires regional strategies for sustainable management of freshwater resources. In Denmark the groundwater quantity and quality is under pressure, and forested areas are considered to protect groundwater reservoirs. However, little is known on how afforestation or forest conversion impacts the water resource at the catchment scale. We hypothesize that the groundwater formation and streamflow is increased when water consuming conifers are replaced with the less consumptive broadleaf tree species. To test this a distributed hydrological model with an energy-based description of evaporation and transpiration processes (MIKE SHE SWET) was used. Large scale hydrological models were established for two geologically (sandy/clayey) contrasting catchments in Denmark; Skjern and Lejre catchments. Land use scenarios were defined with forest vegetation (conifer/broadleaf) and agricultural crops (grass, maize, wheat and barley) in different areal combinations. Initially, the SWET component was calibrated against plot scale field data from two forest sites to obtain vegetation parameter estimates for conifers and broadleaves. Subsequently, the catchment models were run for 10 years with predefined land use scenarios. MIKE SHE SWET simulated canopy interception and throughfall for conifers and broadleaf forests satisfactorily. The catchment simulations showed that replacing current conifer forests with broadleaves, resulted in a significant increase in groundwater recharge and groundwater level, especially in the Skjern catchment with predominantly sandy soils. Also, doubling the forest area, as intended by national legislations, using only broadleaves did not negatively affect the groundwater generation or minimum stream discharge compared to current conditions at Skjern. However, because the shallow geology in the Lejre catchment are dominated by clayey glacial moraine deposits with low hydraulic conductivity, increased net precipitation in areas covered by broadleaf forests would primarily discharge as overland flow or drainage flow rather than contributing to groundwater formation.

Hydrochemical characteristics and evaluation of the granite aquifer in the Alwadeen area, southwest Saudi Arabia

This study was carried out in the Alwadeen area of Khamis Mushayt district of southwestern Saudi Arabia to evaluate the hydrochemical characteristics of the shallow hard rock aquifers. These hard rock aquifers mostly comprise granites and contain significant quantities of groundwater that complement the available groundwater from the unconsolidated alluvial sediments in the nearby wadis. The field investigation indicates two main fracture sets which intersect each other and are oriented in the west-northwest and east-west directions. The granitic rocks in the area are intruded by coarse-grained and quartz-rich monzogranite and pegmatite veins. Hydrogeologically, the fracture systems are important since they facilitate the groundwater storage and assume the transmissive function during times of groundwater abstraction. Given the fact that groundwater in the fractured rock aquifers generally occurs at shallow depths, it may be exposed to contamination from surface and/or near-surface sources, and it is therefore important to evaluate its quality. To this end, a hydrochemical analysis was carried out on six groundwater samples collected from the area. The hydrochemistry revealed that the groundwater is fairly fresh, and facies analysis reveals mixed Na-Cl and Ca-Mg-Cl-SO4 types. Overall, the results reveal that the groundwater is saturated with calcite and dolomite, but unsaturated with gypsum and halite. The degree of salinity increases in the direction of the groundwater flow due to increased rock-water interaction.

Investigate the Effect Meteorological and Hydrological Drought on Groundwater Quantity and Quality (Case Study: Marand Plain)

Investigate the Effect Meteorological and Hydrological Drought on Groundwater Quantity and Quality (Case Study: Marand Plain)

Evaluation of groundwater quality in parts of the Southern Gangetic Plain using water quality indices

In India, persistent dependence on groundwater for intensively irrigated agriculture, industrial use and domestic activities imposes substantial threat to the quality and quantity of groundwater. This study assesses the suitability of groundwater for drinking purposes in parts of the Southern Gangetic Plain based on samples collected from 33 dug wells. In this scope, two robust indices are utilized, namely Groundwater Quality Index (GQI) and the Canadian Council of Ministers of the Environment (CCME) Water Quality Index (CCME_WQI), to assess the overall quality of groundwater by integrating observed water quality determinants like pH, TDS and major ion concentration. The concentration of major anions and cations is observed to be in the order of HCO3 − > Cl− > SO4 2− > NO3 − and Na+ > Ca2+ > Mg2+ > K+, respectively. The pH values of the analyzed samples vary between 6.2 and 7.37 during the post-monsoon (POM) period and between 6.6 and 7.9 during the pre-monsoon (PRM) period. Similarly, TDS concentrations are observed to vary between 6.7 and 1535 mg/l (POM) and 1.43 and 1327 mg/l (PRM). The values of GQI in the study area range between 10.41–108.56 and 16.03–130.06 for the PRM and POM periods, respectively. Among the groundwater samples collected during the PRM period, about 21, 73 and 6% are found to be excellent, good and poor quality, respectively. While the percentage of poor quality water for POM period is exactly the same as that of PRM, about 42 (52%) of the samples are found to be of excellent (good) quality for drinking purposes. The analysis of CCME_WQI for groundwater samples reveals that 3 (21%), 42 (36%), 33 (18%), 21 (24%) of the samples collected during PRM (POM) are classified to be of excellent, good, fair and marginal category, respectively. The spatial distribution of GQI and CCME_WQI illustrates that excellent quality water occurs primarily in the northeast part of the study area during the POM period. However, some localized patches with excellent quality are also observed in both the seasons. Results from this study will be crucial for proper utilization and management of already depleted groundwater resources of the study area.

Geochemical and isotopic mass balances of kettle lakes in southern Quebec (Canada) as tools to document variations in groundwater quantity and quality

Given increasing anthropogenic and climatic pressures on water resources, groundwater and surface water need to be better managed and preserved. As these two water stocks can be connected to each other, their evolutions are linked and need to be considered as such. However, interactions between lakes and groundwater are not well understood and, most of the time, are not taken into account. Therefore, establishing a comprehensive approach to quantify groundwater and lakes’ hydrogeochemical interactions in various settings is of foremost importance for assessing the sensitivity of lakes to groundwater evolution. In this study, small kettle lakes set in fluvioglacial deposits and that are most likely well connected to shallow unconfined aquifers are specifically targeted. Geochemistry and isotopic results highlight that groundwater flux to the lakes is generally the dominant parameter of the lake water budget. The 222Rn results in particular suggest that 38% of the studied lakes have a high proportion of groundwater in their balances. It appears that the different tracers are complementary: geochemistry is influenced by groundwater inflows, reflecting its quality and the local geology, whereas water stable isotopes correspond directly to the volumetric lake water budget, and both of these tracers are impacted by in-lake processes. Moreover, the third tracer considered, 222Rn, highlights the location of groundwater inputs in space and time. Finally, the studied kettle lakes are characterized by a short to medium flushing time by groundwater. As a result, these lakes can be highly sensitive to environmental and climate changes affecting groundwater.

Temporary fluoride concentration changes in groundwater in the context of impact assessment in the Vaniyar sub-basin, South India

India’s surface water and groundwater distribution is temporally variable due to the monsoon. Agriculture is one of the dominant economic sectors in India. Groundwater quality is regularly assessed to determine usability for drinking and irrigation. In this study, World Health Organization and Bureau of Indian Standards guidelines were used to determine suitability of groundwater near artificial recharge structures (ARS) with a focus on the structures´ impact on groundwater quality. Groundwater resources were evaluated for irrigation suitability using electrical conductivity (EC), sodium adsorption ratio, the US Salinity Laboratory diagram, sodium concentration, Wilcox’s diagram, Kelly’s index, and Doneen’s permeability index. EC and major ions were tested in recharge areas at different distances from the ARS. The construction of ARS at optimal distances along major streams has improved groundwater quantity and quality in the sub-basin. Before construction of ARS, fluoride concentrations were higher; after construction, fluoride was reduced in most locations. Water stored in the check dam and groundwater in the wells closer to the structure were suitable for both drinking and irrigation purposes. Impact of ARS on nearby groundwater quality was observed at Pallipatti, Mulayanur, Venkadasamuthram, Pudupatti, Poyyappatti, Harur1, and Sekkampatti. More distant sites included Pappiredipatti, Nambiyappati, Menasi, Harur, Todampatti, and Adikarapatti. Data demonstrated improved groundwater quality in the area of the ARS. Through recharge, the non-potable fluoride in the region is reduced to the permissible limit for human consumption.

Monitoring Groundwater and Its Suitability for Drinking and Irrigation Purposes in the Sharif Abad Basin, Central Iran

The purpose of this study was to analyze the quality and quantity of groundwater in Sharif Abad Basin, located in Central Iran. The analysis of data collected from 24 observation wells indicated that the mean water table has plummeted about 0.896 m/year during 19 years between 1993 and 2013 due to illegal groundwater pumping, which is the main cause of groundwater quality deterioration in this area. Seventeen samples were collected and analyzed to study physicochemical characteristics of groundwater such as pH, Hardness, Chloride (Cl), Electrical Conductivity (EC) and Total Dissolved Solids (TDS) values. The results were compared to drinking water quality standard published by World Health Organization (WHO) and it was concluded that none of the water samples was potable. The spatial distribution of anions and cations followed an increasing pattern eastwards towards the Salt Lake. The analysis of Hydrochemical facies of groundwater using Piper diagram indicated that the major type of groundwater in this basin is Na-Cl, which is mainly different from common type of fresh water in Iran (Ca-HCO3). Suitability of groundwater for irrigation purpose was assessed using Wilcox diagram and it was shown that all the water samples in 2013 belonged to C4S4 category, meaning they were not suitable for irrigation either. According to the ratio of chloride-bicarbonate, 100% of the samples were contaminated by saltwater intrusion. Also, the sodium-chloride ratio indicated that almost 60% of samples were contaminated by Halite solution. The presence of this solution proves the presence of salt domes in this area.

Parameter estimation of aquifer transmissivity variogram using WLS, GA and PSO algorithms

This study focuses on the parameters estimation of aquifer transmissivity (T) variogram; sill, nugget effect and range using the weighted least square (WLS), continuous genetic algorithm (CGA) and particle swarm optimisation (PSO) algorithms. Three types of semivariograms including the spherical, Gaussian and exponential have been used to select the best-fitted model for corresponded empirical values. The objective function for this optimisation procedure is minimising the sum of deviation squares between theoretical and the empirical semivariogram values. These models have been applied with the transmissivity data of Qazvin plane aquifer which is located in north of Iran. The kriged values of T over the aquifer indicate that the simulated results based on PSO have the lowest estimation variance and most reliability in modelling of spatial structure of transmissivity compared to other optimisation algorithms (GA and WLS). Results show that if the kriging technique combined with the PSO algorithm, it would promote to a promising tool in estimation of spatial structures of aquifer transmissivity and be effective in groundwater quality and quantity management.