In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highw...In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highways,railroads,and water supply pipelines,was particularly severe in areas where these structures intersected the seismogenic fault.Critical infrastructure projects that traverse active faults are susceptible to the influence of fault movement,pulse velocity,and ground motions.In this study,we used a unique approach to analyze the acceleration records obtained from the seismic station array(9 strong ground motion stations)located along the East Anatolian Fault(the seismogenic fault of the MW7.8 mainshock of the 2023 Türkiye earthquake doublet).The acceleration records were filtered and integrated to obtain the velocity and displacement time histories.We used the results of an on-site investigation,jointly conducted by China Earthquake Administration and Türkiye’s AFAD,to analyze the distribution of PGA,PGV,and PGD recorded by the strong motion array of the East Anatolian Fault.We found that the maximum horizontal PGA in this earthquake was 3.0 g,and the maximum co-seismic surface displacement caused by the East Anatolian Fault rupture was 6.50 m.As the fault rupture propagated southwest,the velocity pulse caused by the directional effect of the rupture increased gradually,with the maximum PGA reaching 162.3 cm/s.We also discussed the seismic safety of critical infrastructure projects traversing active faults,using two case studies of water supply pipelines in Türkiye that were damaged by earthquakes.We used a three-dimensional finite element model of the PE(polyethylene)water pipeline at the Islahiye State Hospital and fault displacement observations obtained through on-site investigation to analyze pipeline failure mechanisms.We further investigated the effect of the fault-crossing angle on seismic safety of a pipeline,based on our analysis and the failure performance of the large-diameter Thames Water pipeline during the 1999 Kocaeli earthquake.The seismic method of buried pipelines crossing the fault was summarized.展开更多
Bangladesh is a south Asian Monsoonal Country and the recent precipitation pattern in the Cox’s Bazar area of Bangladesh is changing and increasing the number of monsoonal slope failures and landslide hazards in the ...Bangladesh is a south Asian Monsoonal Country and the recent precipitation pattern in the Cox’s Bazar area of Bangladesh is changing and increasing the number of monsoonal slope failures and landslide hazards in the Kutubpalong & Balukhali Rohingya camp area. An attempt has been made to see the influence of seasonal variation of ground water level (G.W.L.) fluctuations on the stability of the eco hills and forests of Ukhiya Teknaf region. Ukhiya hills are in great danger because of cutting trees from the hill slopes and it is well established that due to recent change of climate, short term rainfall for few consecutive days during monsoon might show an influence on the factor of safety (Fs) values of the camp hill slopes. A clear G.W.L. variation between dry and wet seasons has an influence on the stability (Fs) values indicating that climate has a strong influence on the stability and threatening sustainable development. A stable or marginally stable slope might be unstable during raining and show a variation of ground water level (G.W.L.). The generation of pore water pressure (P.W.P.) is also influenced by seasonal variation of ground water level. During wet season negative P.W.P. called suction plays an important role to occur slope failures in the Ukhiya hills. Based on all calculated factor of safety values (Fs) at different locations, four (4) susceptible landslide risk zones are identified. They are very high risk (Fs = 0.18 to 0.46), high risk (Fs = 0.56 to 0.75), medium risk (Fs = 0.76 to 1.0) and marginally stable areas (Fs ≈ 1). Proper geo-engineering measures must be taken by the concerned authorizes to reduce P.W.P. during monsoon by installing rain water harvesting system, allowing sufficient drainage & other geotechnical measures to reduce the risk of slope failures in the Ukhiya hills. Based on the stability factor (Fs) at different slope locations of the camp hills, a risk map of the investigated area has been produced for the local community for their safety and to build up awareness & to motivate them to evacuate the site during monsoonal slope failures. The established “Risk Maps” can be used for future geological engineering works as well as for sustainable planning, design and construction purposes relating to adaptation and mitigation of landslide risks in the investigated area.展开更多
The main objective of the study was to delineate Ground Water Potential Zones(GWPZ)in Mberengwa and Zvishavane districts,Zimbabwe,utilizing geospatial technologies and thematic mapping.Various factors,including geolog...The main objective of the study was to delineate Ground Water Potential Zones(GWPZ)in Mberengwa and Zvishavane districts,Zimbabwe,utilizing geospatial technologies and thematic mapping.Various factors,including geology,soil,rainfall,land use/land cover,drainage density,lineament density,slope,Terrain Ruggedness Index(TRI),and Terrain Wetness Index(TWI),were incorporated as thematic layers.The Multi Influencing Factor(MIF)and Analytical Hierarchical Process(AHP)techniques were employed to assign appropriate weights to these layers based on their relative significance,prioritizing GWPZ mapping.The integration of these weighted layers resulted in the generation of five GWPZ classes:Very high,high,moderate,low,and very low.The MIF method identified 3%of the area as having very high GWPZ,19%as having high GWPZ,40%as having moderate GWPZ,24%as having low GWPZ,and 14%as having very low GWPZ.The AHP method yielded 2%for very high GWPZ,14%for high GWPZ,37%for moderate GWPZ,37%for low GWPZ,and 10%for very low GWPZ.A strong correlation(ρof 0.91)was observed between the MIF results and groundwater yield.The study successfully identified regions with abundant groundwater,providing valuable target areas for groundwater exploitation and highvolume water harvesting initiatives.Accurate identification of these crucial regions is essential for effective decision-making,planning,and management of groundwater resources to alleviate water shortages.展开更多
In order to solve the problems of surface runoff increase,water accumulation in rainy days and urban heat island effect,an ecological outdoor ground structure with composite water storage and drainage functions was st...In order to solve the problems of surface runoff increase,water accumulation in rainy days and urban heat island effect,an ecological outdoor ground structure with composite water storage and drainage functions was studied and applied in this paper:Through the comprehensive design of road ground,road inspection well,garden inspection well and drainage pipe network,it can quickly store and drain ground water,alleviate the urban heat island effect,realize plant infiltration irrigation,and achieve the purpose of saving water and energy.展开更多
This paper explains various factors that contribute to saltwater intrusion, including overexploitation of freshwater resources and climate change as well as the different techniques essential for effective saltwater i...This paper explains various factors that contribute to saltwater intrusion, including overexploitation of freshwater resources and climate change as well as the different techniques essential for effective saltwater intrusion management. The impact of saltwater intrusion along coastal regions and its impact on the environment, hydrogeology and groundwater contamination. It suggests potential solutions to mitigate the impact of saltwater intrusion, including effective water management and techniques for managing SWI. The application of A.I (assessment index) serves as a guideline to correctly identify wells with SWI ranging from no intrusion, slight intrusion and strong intrusion. The challenges of saltwater intrusion in Lagos and the salinization of wells were investigated using the hydro-chemical parameters. The study identifies four wells (“AA”, “CMS”, “OBA” and “VIL”) as having high electric conductivities, indicating saline water intrusion, while other wells (“EBM”, “IKJ, and “IKO”) with lower electric conductivities, indicate little or no salt-water intrusion, and “AJ” well shows slight intrusion. The elevation of the wells also played a vital role in the SWI across coastal regions of Lagos. The study recommends continuous monitoring of coastal wells to help sustain and reduce saline intrusion. The findings of the study are important for policymakers, researchers, and practitioners who are interested in addressing the challenges of saltwater intrusion along coastal regions. We assessed the SWI across the eight (8) wells using the Assessment Index to identify wells with SWI. Wells in “CMS” and “VIL” has strong intrusions. A proposed classification system based on specific ion ratios categorizes water quality from good (+) to highly (-) contaminated (refer to Table 4). These findings underscore the need for attention and effective management strategies to address groundwater unsuitability for various purposes.展开更多
Ground Water Vistas软件是目前国际上盛行的三维地下水水流和溶质运移模拟的图形使用界面.本文介绍了Ground Water Vistas在三种模式下的功能,分析评述了它的优缺点.并以美国Edwards含水层Barton泉稳定流模型为实例,展示了Ground Water...Ground Water Vistas软件是目前国际上盛行的三维地下水水流和溶质运移模拟的图形使用界面.本文介绍了Ground Water Vistas在三种模式下的功能,分析评述了它的优缺点.并以美国Edwards含水层Barton泉稳定流模型为实例,展示了Ground Water Vistas强大的前处理、后处理功能及其优良的三维可视化效果.Edwards含水层喀斯特发育程度极高,其模型研究对我国喀斯特地区地下水资源的评价与管理具有借鉴意义和指导作用.展开更多
The functioning mechanism of groundwater and its make-up water in the process of ground subsidence was studied from such three aspects as osmotic corrasion, osmotic pressure effect and concretion effect, As to osmotic...The functioning mechanism of groundwater and its make-up water in the process of ground subsidence was studied from such three aspects as osmotic corrasion, osmotic pressure effect and concretion effect, As to osmotic corrasion, its forming conditions, mechanical mechanism and process were analyzed, As to osmotic pressure effect, it was mainly studied from hydrostatic pressurizing effect, sop softening effect and negative pressure sealing effect. Through concretion and saturation of soil, the factors of concretion settlement were analyzed. The results showed that both groundwater and its make-up water are important triggering factors to ground subsidence.展开更多
Soil salinity is the most important factor affecting vegetation distribution,and the secondary salinization has affected the development of oasis agriculture.In arid areas the spatial variation of soil moisture and sa...Soil salinity is the most important factor affecting vegetation distribution,and the secondary salinization has affected the development of oasis agriculture.In arid areas the spatial variation of soil moisture and sa lt content is marked-ly affected by groundwater,irratio nal irrigation in artificial oasis.By analyzing the soil moisture,salt content and groundwa-ter table in different areas of old oasis,new oasis and desert in Fukang Oa sis,it is shown that topography and l and use are main factors affecting the change of groundwater table,the redistribution of soil moisture and salt cont ent.When undis-turbed by human,the groundwater tab le rises from mountain to belt of grou nd water spillage,the groundwater t able rises mightily in plain because of the artificial irrigation,and the secondary salinization of soil is very seriou s.In oasis the ground-water table raises compared with that in the natural desert at the same latitude.In old oasis of upper reaches o f river salt has not been concentrated too much in rhizosphere because this area is the belt of groundwater drainage,soil t exture is coarse,the groundwater table is very low,and the salt in soil is drained i nto the groundwater.The new oasis has been the areas of salt accumulation becau se of the artificial irrigation,the salt content in soil is higher than th at in old oasis,so some cultivated fields here had to be thrown out because of the serious s econdary salinization.展开更多
Based on the natural and social conditions as well as hydrogeological characteristics of the Ryukyu limestone, a major aquifer in the Ryukyu Islands, a conception of underground dam, was proposed in the early 1970s in...Based on the natural and social conditions as well as hydrogeological characteristics of the Ryukyu limestone, a major aquifer in the Ryukyu Islands, a conception of underground dam, was proposed in the early 1970s in order to develop ground water resources in the Quaternary Ryukyu limestone regions of Japan. The practice of nearly thirty years has shown that the underground dam is an environment-friendly and effective way for developing ground water in these regions.展开更多
Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water fo...Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water for inhabitants of these communities without any form of treatment. 55 borehole water sites spread within these five sample sub-areas. The metal ions were analyzed using Solar Unicam flame Atomic Absorption Spectrophotometer. Sulphate, phosphate, and cyanide contents were determined by colorimetric method. Results indicate the presence of sodium, calcium, sulphate, and phosphate. However, barium and cyanide were below detection limit. Secondly, there was a relatively higher proportion of calcium and sulphate than sodium and phosphate in its aquifer. Thirdly, a mean ratio value of 0.018 and 0.158 was observed for the ratios of Na+/Ca2+ and ?respectively. Fourthly, sodium showed good correlation with all the other parameters. Finally, nearly all the studied parameters have concentrations below the maximum contaminant levels of the World Health Organization (WHO), invariably inferring that the water is wholesome with respect to the analytes. However, concern still remains from a health point of view on the sodium concentrations in many sample areas.展开更多
Heavy metal contamination of the groundwater of south West Bank in Palestine was assessed. The groundwater samples were analyzed for different trace heavy metals (Tl, Pb, Bi, Cr, Mn, Co, Ni, Cu, Zn, Mo, Ag, and Cd), a...Heavy metal contamination of the groundwater of south West Bank in Palestine was assessed. The groundwater samples were analyzed for different trace heavy metals (Tl, Pb, Bi, Cr, Mn, Co, Ni, Cu, Zn, Mo, Ag, and Cd), and Al content by ICP/MS. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in four different dates of the year (October 2012, November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date. A total of 120 water samples were collected from the ten wells. The samples were analyzed for their pH, electrical conductivity, total dissolved solids, and different trace metals content. The pH, electrical conductivity, and total dissolved solids of all water samples were found to be within the US Environmental protection Agency limits. Results showed that Pb, Al, Cr, Co, Ni, Cu, Zn, and Mo were detected in all water samples analyzed in this study, while Tl, Bi, Mn, Ag, and Cd were detected in 80%, 88%, 90%, 75%, and 95% of the water samples analyzed in this study, respectively. In general, 93% of all samples analyzed contained one or more of the 13 metals studied each in varying concentration. Furthermore, results showed that the concentration of Cr, Mn, Ni, Cu, Zn, and Mo is within the allowed WHO limits in drinking water. However the concentration of Pb Cd, and Al are found to be higher than the allowed WHO limits in 40%, 8%, and 33% of the water samples analyzed in this study, respectively. Statistical analyses showed that concentrations of the metals studied in this study vary significantly between the ten ground water wells, indicating that the wells analyzed in this study is different from each other in terms of heavy metal content. Additionally, from the statistical results obtained, it was found that there is a significant difference in the concentration of the metals in each well for the four sampling times (October 2012, November 2012, March 2013, and April 2013), denoting that metal concentration in the wells vary significantly with sampling time. The results obtained from this study suggest a possible risk to the population of the study area given the toxicity of these metals, and the fact that for many people in the study area, ground water is a main source of their water supply.展开更多
Large amounts of ground ice are born with permafrost on the Qinghai-Tibet Plateau.Degradation of permafrost resulted from the climate warming will inevitably lead to melting of ground ice.The water released from the m...Large amounts of ground ice are born with permafrost on the Qinghai-Tibet Plateau.Degradation of permafrost resulted from the climate warming will inevitably lead to melting of ground ice.The water released from the melting ground ice enters hydrologic cycles at various levels,and changes regional hydrologic regimes to various degrees.Due to difficulties in monitoring the perma-frost-degradation-release-water process,direct and reliable evidence is few.The accumulative effect of releasing water,however,is remarkable in the macro-scale hydrologic process.On the basis of the monitoring results of water-levels changes in some lakes on the Qinghai-Tibet Plateau,and combined with the previous results of the hydrologic changing trends at the regional scale,the authors preliminarily discussed the possibilities of the degrading permafrost on the Qinghai-Tibet Plateau as a potential water source during climate warming.展开更多
The aim of study is to investigate the removal ability of some natural adsorbents for fluoride ion from aqueous solution. The batch dynamic adsorption method was carried out at neutral pH as the functions of contact t...The aim of study is to investigate the removal ability of some natural adsorbents for fluoride ion from aqueous solution. The batch dynamic adsorption method was carried out at neutral pH as the functions of contact time, adsorbent dose, adsorbate concentration, temperature and effect of co-anions, which are commonly present in water. The sorption kinetics and equilibrium adsorption isotherms of fluoride on natural adsorbing materials had been investigated at afore-mentioned optimized. Equilibrium adsorption isotherms, viz., Freundlich and Langmuir isotherms were investigated. Lagergren and Morris-Weber kinetic equations were employed to find the rate constants. The negative enthalpy ΔH = -46.54 KJ·mol-1 and Gibbs free energy calculated was ΔG288-333—(2.07785, 3.08966, 4.1064, 4.90716 and 5.38036 KJ·mol-1) respectively, envisage exothermic and spontaneous nature of sorption.展开更多
Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr...Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr, Ba, K, Bi) that most of them usually have no maximum acceptable limits as either they are considered not to be toxic to human health or there is no sufficient data about their toxicity to human health. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in three different dates of the year (November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date;so a total of 90 water samples were collected from the ten wells. The results obtained from this study suggest a possible risk to the population of the study area given the high concentration of some metals that have no maximum allowed concentration, and the fact that for many people in the study area, ground water is a main source of their water supply.展开更多
Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Resu...Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Results show that observed gravity variation in this area increased continuously,basically reflecting a trend toward land subsidence.With the effect of this subsidence removed,a dominantnegative change in gravity variation was evident,reflecting an average rate of decrease in terrestrial water in this area of 0.10±0.053 m/y,and this is equivalent to a volume of 81.5±43.2×108 m^(3)and is consistent with the spatial distribution of groundwater change from measured hydrologic data.These results can be an essential reference and supplement for the study of terrestrial water variation in the Hebei plain area,and indicate that ground surface gravimetry can be used as an important mean for studying changes in terrestrial water.展开更多
If you drill a hole into the ground,in most places its bottom fills with water after a few days.The water appears even if no rain falls and no streams flow nearby.The water that seeps into the hole is part of the vast...If you drill a hole into the ground,in most places its bottom fills with water after a few days.The water appears even if no rain falls and no streams flow nearby.The water that seeps into the hole is part of the vast reservoir of subterranean ground water that saturates the Earth’s crust in a zone between a few meters and a few kilometers below the surface. Ground water is exploited by digging wells and pumping the water to the surface.It provides drinking water for more than half of the population of North America and is a major source of water for展开更多
Climate change is becoming a serious issue nowadays.There are profound environmental,economic and political implications of global warming. Ecosystems,from mountains to oceans and from the poles to the tropics,are und...Climate change is becoming a serious issue nowadays.There are profound environmental,economic and political implications of global warming. Ecosystems,from mountains to oceans and from the poles to the tropics,are undergoing rapid change.The cost will be borne by all,but especially by the展开更多
According to both the general formula of ground surface displacement by drainage from a well for radial permeable flow of underground water and the drawdown expressions for the flow in multilayered structural aquifers...According to both the general formula of ground surface displacement by drainage from a well for radial permeable flow of underground water and the drawdown expressions for the flow in multilayered structural aquifers, we have derived the analytical expressions of surface displacement induced by steady flow withdrawal from a full penetrating well on phreatic water and confined water in multilayered structural aquifers and discussed the numerial integration scheme of these analytical expressions. And by means of Hermite′s quadrature formula with 20 nodes, we have made calculational programs and examples to show that the methods mentioned in this paper are effective. We think that these methods lay a foundation to study quantitatively crustal deformation due to groundwater drainage when we are engaged in high precision dynamic geodetic measurement on the area of steady flow of multilayered aquifers.展开更多
Modeling and forecasting of the groundwater water table are a major component of effective planning and management of water resources. One way to predict the groundwater level is analysis using a non-deterministic mod...Modeling and forecasting of the groundwater water table are a major component of effective planning and management of water resources. One way to predict the groundwater level is analysis using a non-deterministic model. This study assessed the performance of such models in predicting the groundwater level at Kashan aquifer. Data from 36 piezometer wells in Kashan aquifer for 1999 to 2010 were used. The desired statistical interval was divided into two parts and statistics for 1990 to 2004 were used for modeling and statistics from 2005 to 2010 were used for valediction of the model. The Akaike criterion and correlation coefficients were used to determine the accuracy of the prediction models. The results indicated that the AR(2) model more accurately predicted ground water level in the plains;using this model, the groundwater water table was predicted for up to 60 mo.展开更多
This study investigated the quality of ground water in Baba I, North-West Cameroon, in order to determine its suitability for domestic uses following World Health Organisation (WHO) guidelines. Inhabitants of this loc...This study investigated the quality of ground water in Baba I, North-West Cameroon, in order to determine its suitability for domestic uses following World Health Organisation (WHO) guidelines. Inhabitants of this locality consume water from these sources without any prior treatment which can lead to health problems if the water sources are contaminated. Six water sources were sampled in November 2017, January, April and July 2018 and examined for organoleptic, physico-chemical and bacteriological parameters using standard methods. Results of organoleptic and physical parameters showed that most of the sources were within the WHO acceptable limits with pH varying from moderately acidic to weakly basic. Chemical properties revealed that all the analysed ions were found within the WHO guidelines and the water sources ranged from soft (hardness +, K+, Ca2+, Mg2+, NO3-? and NH4+??(p Escherichia coli, Enterobacter, Streptococcus, Salmonella and Shigella spp, were identified in all the sampled waters, suggesting recent contamination of the sources by human or animal faeces. The sources were unfit for domestic uses and thus, exposed the local population to water borne diseases such as typhoid, diarrhoea and dysentery. Hence, home treatment methods such as chlorination, filtration, boiling and solar disinfection should be implemented prior to consumption.展开更多
基金funded by the China National Key Research and Development Program(No.2022YFC3003505)the Fundamental Research Fund for the Central Public-interest Scientific Institutes(No.DQJB23Y01)+1 种基金the National Natural Science Foundation of China(No.52278540)the Fundamental Research Fund for the Central Public-interest Scientific Institutes(No.DQJB22B28).
文摘In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highways,railroads,and water supply pipelines,was particularly severe in areas where these structures intersected the seismogenic fault.Critical infrastructure projects that traverse active faults are susceptible to the influence of fault movement,pulse velocity,and ground motions.In this study,we used a unique approach to analyze the acceleration records obtained from the seismic station array(9 strong ground motion stations)located along the East Anatolian Fault(the seismogenic fault of the MW7.8 mainshock of the 2023 Türkiye earthquake doublet).The acceleration records were filtered and integrated to obtain the velocity and displacement time histories.We used the results of an on-site investigation,jointly conducted by China Earthquake Administration and Türkiye’s AFAD,to analyze the distribution of PGA,PGV,and PGD recorded by the strong motion array of the East Anatolian Fault.We found that the maximum horizontal PGA in this earthquake was 3.0 g,and the maximum co-seismic surface displacement caused by the East Anatolian Fault rupture was 6.50 m.As the fault rupture propagated southwest,the velocity pulse caused by the directional effect of the rupture increased gradually,with the maximum PGA reaching 162.3 cm/s.We also discussed the seismic safety of critical infrastructure projects traversing active faults,using two case studies of water supply pipelines in Türkiye that were damaged by earthquakes.We used a three-dimensional finite element model of the PE(polyethylene)water pipeline at the Islahiye State Hospital and fault displacement observations obtained through on-site investigation to analyze pipeline failure mechanisms.We further investigated the effect of the fault-crossing angle on seismic safety of a pipeline,based on our analysis and the failure performance of the large-diameter Thames Water pipeline during the 1999 Kocaeli earthquake.The seismic method of buried pipelines crossing the fault was summarized.
文摘Bangladesh is a south Asian Monsoonal Country and the recent precipitation pattern in the Cox’s Bazar area of Bangladesh is changing and increasing the number of monsoonal slope failures and landslide hazards in the Kutubpalong & Balukhali Rohingya camp area. An attempt has been made to see the influence of seasonal variation of ground water level (G.W.L.) fluctuations on the stability of the eco hills and forests of Ukhiya Teknaf region. Ukhiya hills are in great danger because of cutting trees from the hill slopes and it is well established that due to recent change of climate, short term rainfall for few consecutive days during monsoon might show an influence on the factor of safety (Fs) values of the camp hill slopes. A clear G.W.L. variation between dry and wet seasons has an influence on the stability (Fs) values indicating that climate has a strong influence on the stability and threatening sustainable development. A stable or marginally stable slope might be unstable during raining and show a variation of ground water level (G.W.L.). The generation of pore water pressure (P.W.P.) is also influenced by seasonal variation of ground water level. During wet season negative P.W.P. called suction plays an important role to occur slope failures in the Ukhiya hills. Based on all calculated factor of safety values (Fs) at different locations, four (4) susceptible landslide risk zones are identified. They are very high risk (Fs = 0.18 to 0.46), high risk (Fs = 0.56 to 0.75), medium risk (Fs = 0.76 to 1.0) and marginally stable areas (Fs ≈ 1). Proper geo-engineering measures must be taken by the concerned authorizes to reduce P.W.P. during monsoon by installing rain water harvesting system, allowing sufficient drainage & other geotechnical measures to reduce the risk of slope failures in the Ukhiya hills. Based on the stability factor (Fs) at different slope locations of the camp hills, a risk map of the investigated area has been produced for the local community for their safety and to build up awareness & to motivate them to evacuate the site during monsoonal slope failures. The established “Risk Maps” can be used for future geological engineering works as well as for sustainable planning, design and construction purposes relating to adaptation and mitigation of landslide risks in the investigated area.
文摘The main objective of the study was to delineate Ground Water Potential Zones(GWPZ)in Mberengwa and Zvishavane districts,Zimbabwe,utilizing geospatial technologies and thematic mapping.Various factors,including geology,soil,rainfall,land use/land cover,drainage density,lineament density,slope,Terrain Ruggedness Index(TRI),and Terrain Wetness Index(TWI),were incorporated as thematic layers.The Multi Influencing Factor(MIF)and Analytical Hierarchical Process(AHP)techniques were employed to assign appropriate weights to these layers based on their relative significance,prioritizing GWPZ mapping.The integration of these weighted layers resulted in the generation of five GWPZ classes:Very high,high,moderate,low,and very low.The MIF method identified 3%of the area as having very high GWPZ,19%as having high GWPZ,40%as having moderate GWPZ,24%as having low GWPZ,and 14%as having very low GWPZ.The AHP method yielded 2%for very high GWPZ,14%for high GWPZ,37%for moderate GWPZ,37%for low GWPZ,and 10%for very low GWPZ.A strong correlation(ρof 0.91)was observed between the MIF results and groundwater yield.The study successfully identified regions with abundant groundwater,providing valuable target areas for groundwater exploitation and highvolume water harvesting initiatives.Accurate identification of these crucial regions is essential for effective decision-making,planning,and management of groundwater resources to alleviate water shortages.
文摘In order to solve the problems of surface runoff increase,water accumulation in rainy days and urban heat island effect,an ecological outdoor ground structure with composite water storage and drainage functions was studied and applied in this paper:Through the comprehensive design of road ground,road inspection well,garden inspection well and drainage pipe network,it can quickly store and drain ground water,alleviate the urban heat island effect,realize plant infiltration irrigation,and achieve the purpose of saving water and energy.
文摘This paper explains various factors that contribute to saltwater intrusion, including overexploitation of freshwater resources and climate change as well as the different techniques essential for effective saltwater intrusion management. The impact of saltwater intrusion along coastal regions and its impact on the environment, hydrogeology and groundwater contamination. It suggests potential solutions to mitigate the impact of saltwater intrusion, including effective water management and techniques for managing SWI. The application of A.I (assessment index) serves as a guideline to correctly identify wells with SWI ranging from no intrusion, slight intrusion and strong intrusion. The challenges of saltwater intrusion in Lagos and the salinization of wells were investigated using the hydro-chemical parameters. The study identifies four wells (“AA”, “CMS”, “OBA” and “VIL”) as having high electric conductivities, indicating saline water intrusion, while other wells (“EBM”, “IKJ, and “IKO”) with lower electric conductivities, indicate little or no salt-water intrusion, and “AJ” well shows slight intrusion. The elevation of the wells also played a vital role in the SWI across coastal regions of Lagos. The study recommends continuous monitoring of coastal wells to help sustain and reduce saline intrusion. The findings of the study are important for policymakers, researchers, and practitioners who are interested in addressing the challenges of saltwater intrusion along coastal regions. We assessed the SWI across the eight (8) wells using the Assessment Index to identify wells with SWI. Wells in “CMS” and “VIL” has strong intrusions. A proposed classification system based on specific ion ratios categorizes water quality from good (+) to highly (-) contaminated (refer to Table 4). These findings underscore the need for attention and effective management strategies to address groundwater unsuitability for various purposes.
文摘Ground Water Vistas软件是目前国际上盛行的三维地下水水流和溶质运移模拟的图形使用界面.本文介绍了Ground Water Vistas在三种模式下的功能,分析评述了它的优缺点.并以美国Edwards含水层Barton泉稳定流模型为实例,展示了Ground Water Vistas强大的前处理、后处理功能及其优良的三维可视化效果.Edwards含水层喀斯特发育程度极高,其模型研究对我国喀斯特地区地下水资源的评价与管理具有借鉴意义和指导作用.
基金financially supported by the National Nature Science Foundation of China (No.50490271)the National Key Technologies R & D Program of China (No.2004BA615A-18).
文摘The functioning mechanism of groundwater and its make-up water in the process of ground subsidence was studied from such three aspects as osmotic corrasion, osmotic pressure effect and concretion effect, As to osmotic corrasion, its forming conditions, mechanical mechanism and process were analyzed, As to osmotic pressure effect, it was mainly studied from hydrostatic pressurizing effect, sop softening effect and negative pressure sealing effect. Through concretion and saturation of soil, the factors of concretion settlement were analyzed. The results showed that both groundwater and its make-up water are important triggering factors to ground subsidence.
文摘Soil salinity is the most important factor affecting vegetation distribution,and the secondary salinization has affected the development of oasis agriculture.In arid areas the spatial variation of soil moisture and sa lt content is marked-ly affected by groundwater,irratio nal irrigation in artificial oasis.By analyzing the soil moisture,salt content and groundwa-ter table in different areas of old oasis,new oasis and desert in Fukang Oa sis,it is shown that topography and l and use are main factors affecting the change of groundwater table,the redistribution of soil moisture and salt cont ent.When undis-turbed by human,the groundwater tab le rises from mountain to belt of grou nd water spillage,the groundwater t able rises mightily in plain because of the artificial irrigation,and the secondary salinization of soil is very seriou s.In oasis the ground-water table raises compared with that in the natural desert at the same latitude.In old oasis of upper reaches o f river salt has not been concentrated too much in rhizosphere because this area is the belt of groundwater drainage,soil t exture is coarse,the groundwater table is very low,and the salt in soil is drained i nto the groundwater.The new oasis has been the areas of salt accumulation becau se of the artificial irrigation,the salt content in soil is higher than th at in old oasis,so some cultivated fields here had to be thrown out because of the serious s econdary salinization.
文摘Based on the natural and social conditions as well as hydrogeological characteristics of the Ryukyu limestone, a major aquifer in the Ryukyu Islands, a conception of underground dam, was proposed in the early 1970s in order to develop ground water resources in the Quaternary Ryukyu limestone regions of Japan. The practice of nearly thirty years has shown that the underground dam is an environment-friendly and effective way for developing ground water in these regions.
文摘Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water for inhabitants of these communities without any form of treatment. 55 borehole water sites spread within these five sample sub-areas. The metal ions were analyzed using Solar Unicam flame Atomic Absorption Spectrophotometer. Sulphate, phosphate, and cyanide contents were determined by colorimetric method. Results indicate the presence of sodium, calcium, sulphate, and phosphate. However, barium and cyanide were below detection limit. Secondly, there was a relatively higher proportion of calcium and sulphate than sodium and phosphate in its aquifer. Thirdly, a mean ratio value of 0.018 and 0.158 was observed for the ratios of Na+/Ca2+ and ?respectively. Fourthly, sodium showed good correlation with all the other parameters. Finally, nearly all the studied parameters have concentrations below the maximum contaminant levels of the World Health Organization (WHO), invariably inferring that the water is wholesome with respect to the analytes. However, concern still remains from a health point of view on the sodium concentrations in many sample areas.
文摘Heavy metal contamination of the groundwater of south West Bank in Palestine was assessed. The groundwater samples were analyzed for different trace heavy metals (Tl, Pb, Bi, Cr, Mn, Co, Ni, Cu, Zn, Mo, Ag, and Cd), and Al content by ICP/MS. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in four different dates of the year (October 2012, November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date. A total of 120 water samples were collected from the ten wells. The samples were analyzed for their pH, electrical conductivity, total dissolved solids, and different trace metals content. The pH, electrical conductivity, and total dissolved solids of all water samples were found to be within the US Environmental protection Agency limits. Results showed that Pb, Al, Cr, Co, Ni, Cu, Zn, and Mo were detected in all water samples analyzed in this study, while Tl, Bi, Mn, Ag, and Cd were detected in 80%, 88%, 90%, 75%, and 95% of the water samples analyzed in this study, respectively. In general, 93% of all samples analyzed contained one or more of the 13 metals studied each in varying concentration. Furthermore, results showed that the concentration of Cr, Mn, Ni, Cu, Zn, and Mo is within the allowed WHO limits in drinking water. However the concentration of Pb Cd, and Al are found to be higher than the allowed WHO limits in 40%, 8%, and 33% of the water samples analyzed in this study, respectively. Statistical analyses showed that concentrations of the metals studied in this study vary significantly between the ten ground water wells, indicating that the wells analyzed in this study is different from each other in terms of heavy metal content. Additionally, from the statistical results obtained, it was found that there is a significant difference in the concentration of the metals in each well for the four sampling times (October 2012, November 2012, March 2013, and April 2013), denoting that metal concentration in the wells vary significantly with sampling time. The results obtained from this study suggest a possible risk to the population of the study area given the toxicity of these metals, and the fact that for many people in the study area, ground water is a main source of their water supply.
基金supported by The Outstanding Youth Foundation ProjectNational Natural Science Foundation of China (Grant No.40625004)+1 种基金the grant of the Western Project Program of the Chinese Academy of Sciences (No.KZCX2-XB2-10)the research project of the State Key Laboratory of Frozen Soil Engineering (SKLFSE-ZQ-06)
文摘Large amounts of ground ice are born with permafrost on the Qinghai-Tibet Plateau.Degradation of permafrost resulted from the climate warming will inevitably lead to melting of ground ice.The water released from the melting ground ice enters hydrologic cycles at various levels,and changes regional hydrologic regimes to various degrees.Due to difficulties in monitoring the perma-frost-degradation-release-water process,direct and reliable evidence is few.The accumulative effect of releasing water,however,is remarkable in the macro-scale hydrologic process.On the basis of the monitoring results of water-levels changes in some lakes on the Qinghai-Tibet Plateau,and combined with the previous results of the hydrologic changing trends at the regional scale,the authors preliminarily discussed the possibilities of the degrading permafrost on the Qinghai-Tibet Plateau as a potential water source during climate warming.
文摘The aim of study is to investigate the removal ability of some natural adsorbents for fluoride ion from aqueous solution. The batch dynamic adsorption method was carried out at neutral pH as the functions of contact time, adsorbent dose, adsorbate concentration, temperature and effect of co-anions, which are commonly present in water. The sorption kinetics and equilibrium adsorption isotherms of fluoride on natural adsorbing materials had been investigated at afore-mentioned optimized. Equilibrium adsorption isotherms, viz., Freundlich and Langmuir isotherms were investigated. Lagergren and Morris-Weber kinetic equations were employed to find the rate constants. The negative enthalpy ΔH = -46.54 KJ·mol-1 and Gibbs free energy calculated was ΔG288-333—(2.07785, 3.08966, 4.1064, 4.90716 and 5.38036 KJ·mol-1) respectively, envisage exothermic and spontaneous nature of sorption.
文摘Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr, Ba, K, Bi) that most of them usually have no maximum acceptable limits as either they are considered not to be toxic to human health or there is no sufficient data about their toxicity to human health. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in three different dates of the year (November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date;so a total of 90 water samples were collected from the ten wells. The results obtained from this study suggest a possible risk to the population of the study area given the high concentration of some metals that have no maximum allowed concentration, and the fact that for many people in the study area, ground water is a main source of their water supply.
基金supported by the Director Foundation of Institute of Seismology,China Earthquake Administration(Grant Nos:IS201726121)the National Natural Science Foundation of China(Grant Nos:41304059)the special earthquake research grant offered by China Earthquake Administration(Grant Nos:201308009,201508009)。
文摘Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Results show that observed gravity variation in this area increased continuously,basically reflecting a trend toward land subsidence.With the effect of this subsidence removed,a dominantnegative change in gravity variation was evident,reflecting an average rate of decrease in terrestrial water in this area of 0.10±0.053 m/y,and this is equivalent to a volume of 81.5±43.2×108 m^(3)and is consistent with the spatial distribution of groundwater change from measured hydrologic data.These results can be an essential reference and supplement for the study of terrestrial water variation in the Hebei plain area,and indicate that ground surface gravimetry can be used as an important mean for studying changes in terrestrial water.
文摘If you drill a hole into the ground,in most places its bottom fills with water after a few days.The water appears even if no rain falls and no streams flow nearby.The water that seeps into the hole is part of the vast reservoir of subterranean ground water that saturates the Earth’s crust in a zone between a few meters and a few kilometers below the surface. Ground water is exploited by digging wells and pumping the water to the surface.It provides drinking water for more than half of the population of North America and is a major source of water for
文摘Climate change is becoming a serious issue nowadays.There are profound environmental,economic and political implications of global warming. Ecosystems,from mountains to oceans and from the poles to the tropics,are undergoing rapid change.The cost will be borne by all,but especially by the
文摘According to both the general formula of ground surface displacement by drainage from a well for radial permeable flow of underground water and the drawdown expressions for the flow in multilayered structural aquifers, we have derived the analytical expressions of surface displacement induced by steady flow withdrawal from a full penetrating well on phreatic water and confined water in multilayered structural aquifers and discussed the numerial integration scheme of these analytical expressions. And by means of Hermite′s quadrature formula with 20 nodes, we have made calculational programs and examples to show that the methods mentioned in this paper are effective. We think that these methods lay a foundation to study quantitatively crustal deformation due to groundwater drainage when we are engaged in high precision dynamic geodetic measurement on the area of steady flow of multilayered aquifers.
文摘Modeling and forecasting of the groundwater water table are a major component of effective planning and management of water resources. One way to predict the groundwater level is analysis using a non-deterministic model. This study assessed the performance of such models in predicting the groundwater level at Kashan aquifer. Data from 36 piezometer wells in Kashan aquifer for 1999 to 2010 were used. The desired statistical interval was divided into two parts and statistics for 1990 to 2004 were used for modeling and statistics from 2005 to 2010 were used for valediction of the model. The Akaike criterion and correlation coefficients were used to determine the accuracy of the prediction models. The results indicated that the AR(2) model more accurately predicted ground water level in the plains;using this model, the groundwater water table was predicted for up to 60 mo.
文摘This study investigated the quality of ground water in Baba I, North-West Cameroon, in order to determine its suitability for domestic uses following World Health Organisation (WHO) guidelines. Inhabitants of this locality consume water from these sources without any prior treatment which can lead to health problems if the water sources are contaminated. Six water sources were sampled in November 2017, January, April and July 2018 and examined for organoleptic, physico-chemical and bacteriological parameters using standard methods. Results of organoleptic and physical parameters showed that most of the sources were within the WHO acceptable limits with pH varying from moderately acidic to weakly basic. Chemical properties revealed that all the analysed ions were found within the WHO guidelines and the water sources ranged from soft (hardness +, K+, Ca2+, Mg2+, NO3-? and NH4+??(p Escherichia coli, Enterobacter, Streptococcus, Salmonella and Shigella spp, were identified in all the sampled waters, suggesting recent contamination of the sources by human or animal faeces. The sources were unfit for domestic uses and thus, exposed the local population to water borne diseases such as typhoid, diarrhoea and dysentery. Hence, home treatment methods such as chlorination, filtration, boiling and solar disinfection should be implemented prior to consumption.