Current Issue : July - September Volume : 2015 Issue Number : 3 Articles : 5 Articles
Accurate and reliable groundwater level forecasting\nmodels can help ensure the sustainable use of a\nwatershedââ?¬â?¢s aquifers for urban and rural water supply. In\nthis paper, three time series analysis methods, Holtââ?¬â??Winters\n(HW), integrated time series (ITS), and seasonal autoregressive\nintegrated moving average (SARIMA), are\nexplored to simulate the groundwater level in a coastal\naquifer, China. The monthly groundwater table depth data\ncollected in a long time series from 2000 to 2011 are\nsimulated and compared with those three time series\nmodels. The error criteria are estimated using coefficient of\ndetermination (R2), Nashââ?¬â??Sutcliffe model efficiency coefficient\n(E), and root-mean-squared error. The results indicate\nthat three models are all accurate in reproducing the\nhistorical time series of groundwater levels. The comparisons\nof three models show that HW model is more accurate\nin predicting the groundwater levels than SARIMA\nand ITS models. It is recommended that additional studies\nexplore this proposed method, which can be used in turn to\nfacilitate the development and implementation of more\neffective and sustainable groundwater management\nstrategies....
The optimal management of water resources\nrequires that the collected hydrogeological, meteorological,\nand spatial data be simulated and analyzed with appropriate\nmodels. In this study, a catchment-scale distributed hydrological\nmodeling approach is applied to simulate water\nstress for the years 2000 and 2050 in a data scarce Pra\nBasin, Ghana. The model is divided into three parts: The\nfirst computes surface and groundwater availability as well\nas shallow and deep groundwater residence times by using\nPOLFLOW model; the second extends the POLFLOW\nmodel with water demand (Domestic, Industrial and\nAgricultural) model; and the third part involves modeling\nwater stress indicesââ?¬â?from the ratio of water demand to\nwater availabilityââ?¬â?for every part of the basin. On water\navailability, the model estimated long-term annual Pra\nriver discharge at the outflow point of the basin, Deboase,\nto be 198 m3/s as against long-term average measurement\nof 197 m3/s. Moreover, the relationship between simulated\ndischarge and measured discharge at 9 substations in the\nbasin scored Nashââ?¬â??Sutcliffe model efficiency coefficient of\n0.98, which indicates that the model estimation is in\nagreement with the long-term measured discharge. The\nestimated total water demand significantly increases from\n959,049,096 m3/year in 2000 to 3,749,559,019 m3/year in\n2050 (p\\0.05). The number of districts experiencing\nwater stress significantly increases (p = 0.00044) from 8 in\n2000 to 21 out of 35 by the year 2050. This study will\namong other things help the stakeholders in water\nresources management to identify and manage water stress\nareas in the basin....
In recent years, delineation of groundwater\nproductivity zones plays an increasingly important role in\nsustainable management of groundwater resource\nthroughout the world. In this study, groundwater productivity\nindex of northeastern Wasit Governorate was delineated\nusing probabilistic frequency ratio (FR) and\nShannonââ?¬â?¢s entropy models in framework of GIS. Eight\nfactors believed to influence the groundwater occurrence in\nthe study area were selected and used as the input data.\nThese factors were elevation (m), slope angle (degree),\ngeology, soil, aquifer transmissivity (m2/d), storativity\n(dimensionless), distance to river (m), and distance to faults\n(m). In the first step, borehole location inventory map consisting\nof 68 boreholes with relatively high yield ([8 l/sec)\nwas prepared. 47 boreholes (70 %) were used as training data\nand the remaining 21 (30 %) were used for validation. The\npredictive capability of each model was determined using\nrelative operating characteristic technique. The results of\nthe analysis indicate that the FR model with a success rate\nof 87.4 % and prediction rate 86.9 % performed slightly\nbetter than Shannonââ?¬â?¢s entropy model with success rate of\n84.4 % and prediction rate of 82.4 %. The resultant\ngroundwater productivity index was classified into five\nclasses using natural break classification scheme: very low,\nlow, moderate, high, and very high. The highââ?¬â??very high\nclasses for FR and Shannonââ?¬â?¢s entropy models occurred\nwithin 30 % (217 km2) and 31 % (220 km2), respectively\nindicating low productivity conditions of the aquifer system.\nFrom final results, both of the models were capable to\nprospect GWPI with very good results, but FR was better\nin terms of success and prediction rates. Results of this\nstudy could be helpful for better management of groundwater\nresources in the study area and give planners and\ndecision makers an opportunity to prepare appropriate\ngroundwater investment plans....
Twelve kerogen samples separated from Miocene sediments from some wells in the offshore Nile Delta in Egypt. The isolated kerogen is investigated by X-Ray diffraction, Rock Eval pyrolysis, Scanning Electron Microscope (SEM) and Palynofacies analysis. The results show that the study formations consist mainly of type III/II kerogens of immature to marginally mature. The kerogen samples can produce gas and oil if optimum maturity stages are reached.The kerogen samples consist of aggregates of various sizes with angular shapes. Some well-preserved structures derived from terrestrial materials, with some marine organic matter input. Palyenofacies study reveals that the amorphous organic matter (AOM) is abundant with opaques and palynomorphs....
It is difficult to completely degrade wastewater\ncontaining refractory pollutants without secondary pollution\nby biological treatment, as well as physicalââ?¬â??chemical\nprocess. Therefore, electrochemical technology has attracted\nmuch attention for its environmental compatibility,\nhigh removal efficiency, and potential cost effectiveness,\nespecially on the industrial wastewater treatment. An effective\nbibliometric analysis based on the Science Citation\nIndex Core Collection database was conducted to evaluate\nelectrochemical technology for water and wastewater\ntreatment related research from 1994 to 2013. The amount\nof publications significantly increased in the last two decades.\nJournal of the Electrochemical Society published the\nmost articles in this field with a top h-index of 90, taking\n5.8 % of all, followed by Electrochimica Acta and Journal\nof Electroanalytical Chemistry. The researchers focused on\ncategories of chemistry, electrochemistry, and materials\nscience. China and Chinese Academy of Sciences were the\nmost productive country and institution, respectively, while\nthe USA, with the most international collaborative articles\nand highest h-index of 130, was the major collaborator with\n15 other countries in top 20 most productive countries.\nMoreover, based on the analysis of author keywords, title,\nabstract, and ââ?¬Ë?KeyWords Plusââ?¬â?¢, a new method named\nââ?¬Ë?ââ?¬Ë?word cluster analysisââ?¬â?¢Ã¢â?¬â?¢ was successfully applied to trace\nthe research hotspot. Nowadays, researchers mainly focused\non novel anodic electrode, especially on its physiochemical\nand electrochemical properties....
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