Through reviewing the flow theory’s birth and development history in underground porous media and contrasting the mechanics of underground fluids and mechanics of viscous fluids, this paper points out the main facto...Through reviewing the flow theory’s birth and development history in underground porous media and contrasting the mechanics of underground fluids and mechanics of viscous fluids, this paper points out the main factors, which affect the development of the theory on oil and gas porous flow. The development law and development route of the mechanics of fluids in porous media are also summarized in this paper.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
The four diversion tunnels at Jinping Ⅱ hydropower station represent the deepest underground project yet conducted in China, with an overburden depth of 1500-2000 m and a maximum depth of 2525 m.The tunnel structure ...The four diversion tunnels at Jinping Ⅱ hydropower station represent the deepest underground project yet conducted in China, with an overburden depth of 1500-2000 m and a maximum depth of 2525 m.The tunnel structure was subjected to a maximum external water pressure of 10.22 MPa and the maximum single-point groundwater inflow of 7.3 m^3/s. The success of the project construction was related to numerous challenging issues such as the stability of the rock mass surrounding the deep tunnels, strong rockburst prevention and control, and the treatment of high-pressure, large-volume groundwater infiltration. During the construction period, a series of new technologies was developed for the purpose of risk control in the deep tunnel project. Nondestructive sampling and in-situ measurement technologies were employed to fully characterize the formation and development of excavation damaged zones(EDZs), and to evaluate the mechanical behaviors of deep rocks. The time effect of marble fracture propagation, the brittleeductileeplastic transition of marble, and the temporal development of rock mass fracture and damage induced by high geostress were characterized. The safe construction of deep tunnels was achieved under a high risk of strong rockburst using active measures, a support system comprised of lining, grouting, and external water pressure reduction techniques that addressed the coupled effect of high geostress, high external water pressure, and a comprehensive early-warning system. A complete set of technologies for the treatment of high-pressure and large-volume groundwater infiltration was developed. Monitoring results indicated that the Jinping II hydropower station has been generally stable since it was put into operation in 2014.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
Most of China's wetland areas are located in Sanjiang Plain (Three River Basin). It's area has 207×104 hm2 of wet and low-lying farmland, of which 59% is cropped. During 1970s and 1980s, the Chinese gover...Most of China's wetland areas are located in Sanjiang Plain (Three River Basin). It's area has 207×104 hm2 of wet and low-lying farmland, of which 59% is cropped. During 1970s and 1980s, the Chinese government organized intensive scientific research into potential changes to existing natural resources conditions for this farmland. The aim was to make the water resources regime beneficial to crop production. Arterial drainage, field drainage and appropriate sub-soil treatments were suggested. The Four Waters converting mechanism and the estimation of the Four Water converting amount in wet and low-lying farmland were discussed in the paper.展开更多
Most of China's wetland areas are located in the Sanjiang Plain.This area has 207×10 4 hm 2 of wet and low lying farmland,of which 59% is cropped.During the 1970s and 1980s,the Chinese government organize...Most of China's wetland areas are located in the Sanjiang Plain.This area has 207×10 4 hm 2 of wet and low lying farmland,of which 59% is cropped.During the 1970s and 1980s,the Chinese government organized intensive scientific research into potential changes to existing natural resources conditions for these farmlands.The aim was to change the water resources regime to one that was beneficial to crop production.Arterial drainage,field drainage and appropriate sub soil treatments were required.The relation between plant products industry and the Four Waters distribution,also the main measures of the Four Waters converting in wet and low lying farmland were discussed in the paper.展开更多
The main purpose of the research is to discuss the influence on ground water by NH4-N in polluted river and river bed.In the lab-scale experiment three kinds of natural sand were chosen as infiltration medium,and poll...The main purpose of the research is to discuss the influence on ground water by NH4-N in polluted river and river bed.In the lab-scale experiment three kinds of natural sand were chosen as infiltration medium,and polluted rivers were simulated by domestic sewage,after 10-month sand column test it was found that NH_4-N came to adsorption sa- turation on the 17th day in coarse sand and on the 130~140th day in medium sand,then had a higher effluent concentration because of desorption.It is concluded that NH_4-N eas- ily moved to ground water.When the concentration of NH_4-N in Liangshui River were 46.86,26.95 mg/L,that in groundwater are less than 1.10 mg/L.It is found that Liangshui River have a little influence on groundwater because of bottom mud,thickness and char- acter of the infiltration medium under the river bed and seepage quantity of river water. Clean water leaching test states that after the silt is cleared away and clean water is poured,NH_4-N in the penetration media under the polluted river is obviously carried into ground water,and ground water is polluted secondly.展开更多
The main purpose of the research is to study the influence on shallow ground water by heavy metal in polluted river. In the lab-scale experiment polluted rivers were simulated by domestic sewage, and three kinds of na...The main purpose of the research is to study the influence on shallow ground water by heavy metal in polluted river. In the lab-scale experiment polluted rivers were simulated by domestic sewage, and three kinds of natural sand were chosen as infiltration medium, it was found that Cr(Ⅵ)penetrated on the 13th day and then had a removal ratio of 77%-99% in coarse sand,over 91% and 96% in two kinds of medium sand. From beginning to end in column 2 and column 3 the removal ratio of lead were greater than 97%. It is difficult for Cr(Ⅵ) and lead to enter ground water. In on-site test it indicates that the concentration of Cr(Ⅵ) in No.1-3 and coal yard well along the bank of Liangshui River is not greater than background concentration in groundwater, so Cr (Ⅵ) in Liangshui River has a little influence on ground water. The mechanism of Cr(Ⅵ) removal is reducing action and sedimentation. The removal mechanism of lead primarily is chemical adsorption and generation deposit. Cr(Ⅵ) mainly is transformed to precipitation by reducing action because of abundant reduction agent in the infiltration media, so the tests indicat that polluted river is not the source of Cr (Ⅵ) pollution in ground water. Generally lead may polluted soil, but not groundwater.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
Ground water is a major source of drinking water. In the Niger Delta, the ground water is unfit for human consumption due to high concentration of iron, coliforms and acidity. In an attempt to make the water potable, ...Ground water is a major source of drinking water. In the Niger Delta, the ground water is unfit for human consumption due to high concentration of iron, coliforms and acidity. In an attempt to make the water potable, groundwater samples were collected from domestic boreholes and analyzed for physicochemical and microbial parameters using standard analytical methods. The groundwater samples were collected after single and double trickling filter treatment. The treated water from the single and double trickling filter was similarly analyzed. Results show that after treatment, iron decreased from 5.23-9.96 mg/L in the raw water to 1.67-2.02 mg/L in the single treatment and 0.05-0.31 mg/L in the double treated water (P 〈 0.05). Similarly, pH increased from 4.39-5.17 in the raw water to 5.31-5.87 in the single treatment and 6.09-6.90 in the double treatment (P 〈 0.05). Coliforms decreased from 60-85 MPN/100 mL in the raw water to 3-10 MPN/100 mL in the single treatment and 0-2 MPN/100 mL in the double treatment (P 〈 0.05). Based on the findings of this study, it is recommended that it is unsafe to drink untreated groundwater as currently practiced in the Niger Delta, but should be subjected to double trickling filter treatment and chlorination before consumption.展开更多
In this paper we discuss ways to obtain information about the quality of ground water and their availability. We classify the different approaches in two categories: geophysical methods, e.g., electroresistivity soun...In this paper we discuss ways to obtain information about the quality of ground water and their availability. We classify the different approaches in two categories: geophysical methods, e.g., electroresistivity sounding, seismic survey, gravimetry, MT (magnetotelluric) method, and geochemical methods. The former ones are able to provide information on the geological structure,meaning depth, range, amount of water and possible connections among different exploration areas or regions at risk due to contamination. On the other hand, the last ones provide information about the quality of water and the possible of use for agriculture, industry or human consumption. As a case study we aim at the Guarani Aquifer, more specifically at its recharge zone on the southern rim.展开更多
The management of peat swamp forests in Malaysia contends with two major issues: forest fires and the effects of abandoned forest-logging drainage systems or canals. Forest fire occurs during low rainfall season relat...The management of peat swamp forests in Malaysia contends with two major issues: forest fires and the effects of abandoned forest-logging drainage systems or canals. Forest fire occurs during low rainfall season related to the local people activities. The drainage networks change the hydrological function of the intact forest ecosystem. A key function of the hydrological system in the undisturbed forest is to absorb water during rainfall season, thus delaying downstream runoff and preventing flash floods. The objective of the project described here is to restore the hydrological function of peat swamp forest (PSF) at Ayer Hitam North Forest Reserve (AHNFR) in Muar, Johor, Malaysia. The oil palm plantations, especially in the southern part of the area affect the forest reserve. Water flows out of the forest reserve through the drainage system constructed for managing these plantations. In 2016 and 2017, two water block structures or check dams were constructed near the boundaries of the forest reserve to hold the water and raise the groundwater level in the forest reserve. The implementation of the check dams at the two locations has conserved the groundwater level and subsequently, about 1.2 million m<sup>3</sup> of water was saved annually from leaving the forest reserve from each of the check dam. This project is also part of the Coca-Cola Company’s sustainability commitment for water strategy with the global that is to replenish 100% of the equivalent volume of water consumed in their products and production by 2020. Replenishment is the key sustainability commitment for the Company.展开更多
Groundwater comprises a large portion of irrigation for California's agriculture, and sustains a wide diversity of ecosystems as well as consumptive use, but pumping is occurring faster than replenishment. At the sam...Groundwater comprises a large portion of irrigation for California's agriculture, and sustains a wide diversity of ecosystems as well as consumptive use, but pumping is occurring faster than replenishment. At the same time, contaminants from fertilizers and pesticides are infiltrating into the groundwater, becoming increasingly concentrated as water is extracted. It compared space-based observations of groundwater anomalies from California's San Joaquin Valley using the GRACE (gravity recovery and climate experiment) against measurements of 42 organic and inorganic chemicals from 41,667 wells in the valley from 2003 to 2010. It compared Arsenic, Boron, Cadmium, Chloride, Selenium, Trichloroethylene, and TDS (total dissolved solid) concentrations with the groundwater storage anomaly from 2003 to 2010. The results show strong correlations for groundwater depletion against increasing chloride (r2= 0.78, p 〈 0.05) and boron (r2 = 0.88, p 〈 0.05). This indicates increasing contaminant concentrations while groundwater was depleting over the last eight years. Solubilization by complexation with Cl, CO3 and/or organic chelates may account for the increasing concentration of some heavy metals when groundwater depletion occurs. These results are the first to link space-based groundwater mass change with groundwater contaminant concentration change.展开更多
Groundwater is the water located beneath the earth's surface in the soil pore spaces and in the fractures of rock formations. As one of the most important natural resources, groundwater is associated with the environ...Groundwater is the water located beneath the earth's surface in the soil pore spaces and in the fractures of rock formations. As one of the most important natural resources, groundwater is associated with the environment, public health, welfare, and long-term economic growth, which affects the daily activities of human beings. In modern urban areas, the primary contaminants of groundwater are artificial products, such as gasoline and diesel. To protect this important water resource, a series of efforts have been exerted, including enforcement and remedial actions. Each year, the TGPC (Texas Groundwater Protection Committee) in US publishes a "Joint Groundwater Monitoring and Contamination Report" to describe historic and new contamination cases in each county, which is an important data source for the design of prevention strategies. In this paper, a DDM (data dependent modeling) approach is proposed to predict county-level NCC (new contamination cases). A case study with contamination information from Harris County in Texas was conducted to illustrate the modeling and prediction process with promising results. The one-step prediction error is 1.5%, while the two-step error is 12.1%. The established model can be used at the county-level, state-level, and even at the country-level. Besides, the prediction results could be a reference during decision-making processes.展开更多
The research centered on the groundwater quality parameters in five boreholes and three wells in residential urban areas of Zimbabwe. Ten runs of chemical analysis for water pH, EC (electrical conductivity), water h...The research centered on the groundwater quality parameters in five boreholes and three wells in residential urban areas of Zimbabwe. Ten runs of chemical analysis for water pH, EC (electrical conductivity), water hardness were carried out weekly and averages were calculated for each at Bindura University laboratory. Iron concentrations analysis was done at the Tobacco Research Station. The results from boreholes and wells were compared to the WHO (World Health Organisation) drinking water acceptable standards to measure the deviations. It was found that the boreholes had hard waters (112 mg/L), EC (425 s/m) and iron concentration (0.49 ppm) outside the WHO standards (〉 64 mg/L; 400 s/m; 0.3 ppm respectively). In contrary the wells had only the water pH slightly outside the acceptable ranges (5.8); other parameters were in the acceptable ranges (EC 379 s/m; water hardness 0.38 mg/L as CaCO3 and iron concentration 0.38 ppm). The difference in chemical composition between the boreholes and wells caused the borehole water rejection in favor of well water. High iron concentrations and water hardness in boreholes were major contributors to the water rejection by the residents.展开更多
Water is one of the essential life’s basic needs. However, the purity and quality of water from groundwater sources in developing countries are still in doubt due to contamination by different anthropogenic activitie...Water is one of the essential life’s basic needs. However, the purity and quality of water from groundwater sources in developing countries are still in doubt due to contamination by different anthropogenic activities. This study assessed the temporal variations in physico-chemical parameters of water sources in Kibujjo Village, Wakiso District, Uganda. Water samples were collected from four water sources: two (2) wells and two (2) boreholes. The levels of both physical and chemical parameters were assessed using APHA standard analytical methods. The results indicated that most of the measured water quality variables did not exceed the UNBS and WHO standards for drinking water, and the majority of the water parameters positively correlated. Borehole waters had a better quality than well waters. The highest levels of most of the variables were recorded during the wet season. There was a significant statistical difference (p SO<sup>2-</sup>4</sub> showed a significant difference in the dry season amongst the water sources but no significant difference during the wet season (p > 0.05). Therefore, water from wells is not recommended for drinking before treatment, most especially during the wet season.展开更多
The sulfurous water deposit exploitation in volcanic, swamp, or wetland regions, represents an alternative option for potable water supply in cities and communities around the world. However, before its consumption, i...The sulfurous water deposit exploitation in volcanic, swamp, or wetland regions, represents an alternative option for potable water supply in cities and communities around the world. However, before its consumption, it must be treated by the application of physicochemical or biological methods with the ability to separate high contents in sulfates, hydrogen sulphite and sulphides which have laxative, allergic and toxic properties in humans. Conventional methods require the supply of chemical compounds or the adequate control of different parameters such as pH, temperature, etc., and the constant maintenance within their reactors. For these reasons, the systems could have elevated operating costs and require additional steps to enable the treatment of its separated products and the final disposal of its residual waste generated. In this research, compound parabolic collectors are implemented for the use of solar energy radiation, UV-B type, in Solar Advanced Oxidation Processes in H2O2/O3/UVsolar homogeneous phase. Its application during the pre-treatment of four sulfur water wells from the region of Puebla, Mexico, demonstrated its ability to transform their sulfur compounds in sulfates of easy removal by a later stage of reverse osmosis, in an approximately 15 min treatment time process.展开更多
It is important to evaluate and monitor the environmental impacts by the activity in our hand with appropriate methods, and the geophysical techniques have often been used in the subsurface environmental monitoring an...It is important to evaluate and monitor the environmental impacts by the activity in our hand with appropriate methods, and the geophysical techniques have often been used in the subsurface environmental monitoring and remediation processes. In the study an electromagnetic survey (EM) is performed to delineate deeply the extent of contamination at an industrial abandoned site, to detect the spread of groundwater and soil contamination, to locate possible pathways of leachate plumes. Based on the analysis of the geophysical anomaly of electrical conductivity, the survey area is delineated into three zones: original zone, transitional zone and contaminated zone. It was inferred that the high conductivity zones correspond to the contaminated zones of groundwater and soil. The survey demonstrates that EM method has the ability to measure small changes in subsurface properties involving ground water and is sensitive to the conductive layers. The measurement shows the behavior of groundwater and soil contamination and the position of groundwater pipelines, and it is beneficial to help waste management processes and to determine possible locations of monitoring wells so as to monitor the environment in the survey area in the future.展开更多
文摘Through reviewing the flow theory’s birth and development history in underground porous media and contrasting the mechanics of underground fluids and mechanics of viscous fluids, this paper points out the main factors, which affect the development of the theory on oil and gas porous flow. The development law and development route of the mechanics of fluids in porous media are also summarized in this paper.
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The four diversion tunnels at Jinping Ⅱ hydropower station represent the deepest underground project yet conducted in China, with an overburden depth of 1500-2000 m and a maximum depth of 2525 m.The tunnel structure was subjected to a maximum external water pressure of 10.22 MPa and the maximum single-point groundwater inflow of 7.3 m^3/s. The success of the project construction was related to numerous challenging issues such as the stability of the rock mass surrounding the deep tunnels, strong rockburst prevention and control, and the treatment of high-pressure, large-volume groundwater infiltration. During the construction period, a series of new technologies was developed for the purpose of risk control in the deep tunnel project. Nondestructive sampling and in-situ measurement technologies were employed to fully characterize the formation and development of excavation damaged zones(EDZs), and to evaluate the mechanical behaviors of deep rocks. The time effect of marble fracture propagation, the brittleeductileeplastic transition of marble, and the temporal development of rock mass fracture and damage induced by high geostress were characterized. The safe construction of deep tunnels was achieved under a high risk of strong rockburst using active measures, a support system comprised of lining, grouting, and external water pressure reduction techniques that addressed the coupled effect of high geostress, high external water pressure, and a comprehensive early-warning system. A complete set of technologies for the treatment of high-pressure and large-volume groundwater infiltration was developed. Monitoring results indicated that the Jinping II hydropower station has been generally stable since it was put into operation in 2014.
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Most of China's wetland areas are located in Sanjiang Plain (Three River Basin). It's area has 207×104 hm2 of wet and low-lying farmland, of which 59% is cropped. During 1970s and 1980s, the Chinese government organized intensive scientific research into potential changes to existing natural resources conditions for this farmland. The aim was to make the water resources regime beneficial to crop production. Arterial drainage, field drainage and appropriate sub-soil treatments were suggested. The Four Waters converting mechanism and the estimation of the Four Water converting amount in wet and low-lying farmland were discussed in the paper.
文摘Most of China's wetland areas are located in the Sanjiang Plain.This area has 207×10 4 hm 2 of wet and low lying farmland,of which 59% is cropped.During the 1970s and 1980s,the Chinese government organized intensive scientific research into potential changes to existing natural resources conditions for these farmlands.The aim was to change the water resources regime to one that was beneficial to crop production.Arterial drainage,field drainage and appropriate sub soil treatments were required.The relation between plant products industry and the Four Waters distribution,also the main measures of the Four Waters converting in wet and low lying farmland were discussed in the paper.
基金the National Natural Science Foundation of China(40772165)
文摘The main purpose of the research is to discuss the influence on ground water by NH4-N in polluted river and river bed.In the lab-scale experiment three kinds of natural sand were chosen as infiltration medium,and polluted rivers were simulated by domestic sewage,after 10-month sand column test it was found that NH_4-N came to adsorption sa- turation on the 17th day in coarse sand and on the 130~140th day in medium sand,then had a higher effluent concentration because of desorption.It is concluded that NH_4-N eas- ily moved to ground water.When the concentration of NH_4-N in Liangshui River were 46.86,26.95 mg/L,that in groundwater are less than 1.10 mg/L.It is found that Liangshui River have a little influence on groundwater because of bottom mud,thickness and char- acter of the infiltration medium under the river bed and seepage quantity of river water. Clean water leaching test states that after the silt is cleared away and clean water is poured,NH_4-N in the penetration media under the polluted river is obviously carried into ground water,and ground water is polluted secondly.
文摘The main purpose of the research is to study the influence on shallow ground water by heavy metal in polluted river. In the lab-scale experiment polluted rivers were simulated by domestic sewage, and three kinds of natural sand were chosen as infiltration medium, it was found that Cr(Ⅵ)penetrated on the 13th day and then had a removal ratio of 77%-99% in coarse sand,over 91% and 96% in two kinds of medium sand. From beginning to end in column 2 and column 3 the removal ratio of lead were greater than 97%. It is difficult for Cr(Ⅵ) and lead to enter ground water. In on-site test it indicates that the concentration of Cr(Ⅵ) in No.1-3 and coal yard well along the bank of Liangshui River is not greater than background concentration in groundwater, so Cr (Ⅵ) in Liangshui River has a little influence on ground water. The mechanism of Cr(Ⅵ) removal is reducing action and sedimentation. The removal mechanism of lead primarily is chemical adsorption and generation deposit. Cr(Ⅵ) mainly is transformed to precipitation by reducing action because of abundant reduction agent in the infiltration media, so the tests indicat that polluted river is not the source of Cr (Ⅵ) pollution in ground water. Generally lead may polluted soil, but not groundwater.
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Ground water is a major source of drinking water. In the Niger Delta, the ground water is unfit for human consumption due to high concentration of iron, coliforms and acidity. In an attempt to make the water potable, groundwater samples were collected from domestic boreholes and analyzed for physicochemical and microbial parameters using standard analytical methods. The groundwater samples were collected after single and double trickling filter treatment. The treated water from the single and double trickling filter was similarly analyzed. Results show that after treatment, iron decreased from 5.23-9.96 mg/L in the raw water to 1.67-2.02 mg/L in the single treatment and 0.05-0.31 mg/L in the double treated water (P 〈 0.05). Similarly, pH increased from 4.39-5.17 in the raw water to 5.31-5.87 in the single treatment and 6.09-6.90 in the double treatment (P 〈 0.05). Coliforms decreased from 60-85 MPN/100 mL in the raw water to 3-10 MPN/100 mL in the single treatment and 0-2 MPN/100 mL in the double treatment (P 〈 0.05). Based on the findings of this study, it is recommended that it is unsafe to drink untreated groundwater as currently practiced in the Niger Delta, but should be subjected to double trickling filter treatment and chlorination before consumption.
文摘In this paper we discuss ways to obtain information about the quality of ground water and their availability. We classify the different approaches in two categories: geophysical methods, e.g., electroresistivity sounding, seismic survey, gravimetry, MT (magnetotelluric) method, and geochemical methods. The former ones are able to provide information on the geological structure,meaning depth, range, amount of water and possible connections among different exploration areas or regions at risk due to contamination. On the other hand, the last ones provide information about the quality of water and the possible of use for agriculture, industry or human consumption. As a case study we aim at the Guarani Aquifer, more specifically at its recharge zone on the southern rim.
文摘The management of peat swamp forests in Malaysia contends with two major issues: forest fires and the effects of abandoned forest-logging drainage systems or canals. Forest fire occurs during low rainfall season related to the local people activities. The drainage networks change the hydrological function of the intact forest ecosystem. A key function of the hydrological system in the undisturbed forest is to absorb water during rainfall season, thus delaying downstream runoff and preventing flash floods. The objective of the project described here is to restore the hydrological function of peat swamp forest (PSF) at Ayer Hitam North Forest Reserve (AHNFR) in Muar, Johor, Malaysia. The oil palm plantations, especially in the southern part of the area affect the forest reserve. Water flows out of the forest reserve through the drainage system constructed for managing these plantations. In 2016 and 2017, two water block structures or check dams were constructed near the boundaries of the forest reserve to hold the water and raise the groundwater level in the forest reserve. The implementation of the check dams at the two locations has conserved the groundwater level and subsequently, about 1.2 million m<sup>3</sup> of water was saved annually from leaving the forest reserve from each of the check dam. This project is also part of the Coca-Cola Company’s sustainability commitment for water strategy with the global that is to replenish 100% of the equivalent volume of water consumed in their products and production by 2020. Replenishment is the key sustainability commitment for the Company.
文摘Groundwater comprises a large portion of irrigation for California's agriculture, and sustains a wide diversity of ecosystems as well as consumptive use, but pumping is occurring faster than replenishment. At the same time, contaminants from fertilizers and pesticides are infiltrating into the groundwater, becoming increasingly concentrated as water is extracted. It compared space-based observations of groundwater anomalies from California's San Joaquin Valley using the GRACE (gravity recovery and climate experiment) against measurements of 42 organic and inorganic chemicals from 41,667 wells in the valley from 2003 to 2010. It compared Arsenic, Boron, Cadmium, Chloride, Selenium, Trichloroethylene, and TDS (total dissolved solid) concentrations with the groundwater storage anomaly from 2003 to 2010. The results show strong correlations for groundwater depletion against increasing chloride (r2= 0.78, p 〈 0.05) and boron (r2 = 0.88, p 〈 0.05). This indicates increasing contaminant concentrations while groundwater was depleting over the last eight years. Solubilization by complexation with Cl, CO3 and/or organic chelates may account for the increasing concentration of some heavy metals when groundwater depletion occurs. These results are the first to link space-based groundwater mass change with groundwater contaminant concentration change.
文摘Groundwater is the water located beneath the earth's surface in the soil pore spaces and in the fractures of rock formations. As one of the most important natural resources, groundwater is associated with the environment, public health, welfare, and long-term economic growth, which affects the daily activities of human beings. In modern urban areas, the primary contaminants of groundwater are artificial products, such as gasoline and diesel. To protect this important water resource, a series of efforts have been exerted, including enforcement and remedial actions. Each year, the TGPC (Texas Groundwater Protection Committee) in US publishes a "Joint Groundwater Monitoring and Contamination Report" to describe historic and new contamination cases in each county, which is an important data source for the design of prevention strategies. In this paper, a DDM (data dependent modeling) approach is proposed to predict county-level NCC (new contamination cases). A case study with contamination information from Harris County in Texas was conducted to illustrate the modeling and prediction process with promising results. The one-step prediction error is 1.5%, while the two-step error is 12.1%. The established model can be used at the county-level, state-level, and even at the country-level. Besides, the prediction results could be a reference during decision-making processes.
文摘The research centered on the groundwater quality parameters in five boreholes and three wells in residential urban areas of Zimbabwe. Ten runs of chemical analysis for water pH, EC (electrical conductivity), water hardness were carried out weekly and averages were calculated for each at Bindura University laboratory. Iron concentrations analysis was done at the Tobacco Research Station. The results from boreholes and wells were compared to the WHO (World Health Organisation) drinking water acceptable standards to measure the deviations. It was found that the boreholes had hard waters (112 mg/L), EC (425 s/m) and iron concentration (0.49 ppm) outside the WHO standards (〉 64 mg/L; 400 s/m; 0.3 ppm respectively). In contrary the wells had only the water pH slightly outside the acceptable ranges (5.8); other parameters were in the acceptable ranges (EC 379 s/m; water hardness 0.38 mg/L as CaCO3 and iron concentration 0.38 ppm). The difference in chemical composition between the boreholes and wells caused the borehole water rejection in favor of well water. High iron concentrations and water hardness in boreholes were major contributors to the water rejection by the residents.
文摘Water is one of the essential life’s basic needs. However, the purity and quality of water from groundwater sources in developing countries are still in doubt due to contamination by different anthropogenic activities. This study assessed the temporal variations in physico-chemical parameters of water sources in Kibujjo Village, Wakiso District, Uganda. Water samples were collected from four water sources: two (2) wells and two (2) boreholes. The levels of both physical and chemical parameters were assessed using APHA standard analytical methods. The results indicated that most of the measured water quality variables did not exceed the UNBS and WHO standards for drinking water, and the majority of the water parameters positively correlated. Borehole waters had a better quality than well waters. The highest levels of most of the variables were recorded during the wet season. There was a significant statistical difference (p SO<sup>2-</sup>4</sub> showed a significant difference in the dry season amongst the water sources but no significant difference during the wet season (p > 0.05). Therefore, water from wells is not recommended for drinking before treatment, most especially during the wet season.
文摘The sulfurous water deposit exploitation in volcanic, swamp, or wetland regions, represents an alternative option for potable water supply in cities and communities around the world. However, before its consumption, it must be treated by the application of physicochemical or biological methods with the ability to separate high contents in sulfates, hydrogen sulphite and sulphides which have laxative, allergic and toxic properties in humans. Conventional methods require the supply of chemical compounds or the adequate control of different parameters such as pH, temperature, etc., and the constant maintenance within their reactors. For these reasons, the systems could have elevated operating costs and require additional steps to enable the treatment of its separated products and the final disposal of its residual waste generated. In this research, compound parabolic collectors are implemented for the use of solar energy radiation, UV-B type, in Solar Advanced Oxidation Processes in H2O2/O3/UVsolar homogeneous phase. Its application during the pre-treatment of four sulfur water wells from the region of Puebla, Mexico, demonstrated its ability to transform their sulfur compounds in sulfates of easy removal by a later stage of reverse osmosis, in an approximately 15 min treatment time process.
文摘It is important to evaluate and monitor the environmental impacts by the activity in our hand with appropriate methods, and the geophysical techniques have often been used in the subsurface environmental monitoring and remediation processes. In the study an electromagnetic survey (EM) is performed to delineate deeply the extent of contamination at an industrial abandoned site, to detect the spread of groundwater and soil contamination, to locate possible pathways of leachate plumes. Based on the analysis of the geophysical anomaly of electrical conductivity, the survey area is delineated into three zones: original zone, transitional zone and contaminated zone. It was inferred that the high conductivity zones correspond to the contaminated zones of groundwater and soil. The survey demonstrates that EM method has the ability to measure small changes in subsurface properties involving ground water and is sensitive to the conductive layers. The measurement shows the behavior of groundwater and soil contamination and the position of groundwater pipelines, and it is beneficial to help waste management processes and to determine possible locations of monitoring wells so as to monitor the environment in the survey area in the future.