In exploiting shallow coal resources in western China, conservation of water resources is often subjugated to considerations of safety and production in coal mines. In order to maintain a sustainable development in th...In exploiting shallow coal resources in western China, conservation of water resources is often subjugated to considerations of safety and production in coal mines. In order to maintain a sustainable development in the Shenfu-Dongsheng coalfield, we propose a technology of constructing groundwater reservoirs in goafs in shallow coalfields to protect fragile ecological environments. Given the premise of safe production, we selected an appropriate goaf as the site for constructing a groundwater reservoir and used a mine water recharge technique in combination with other related techniques for effective water conservation. Then filtering and purification techniques were used to purify the mine water given the physical and chemical properties of mine water and its filling material, ,thereby greatly reducing suspended matter, calcium and other harmful ions in the water. With the potential of widely application, the research result has been successfully applied in the Daliuta coal mine, to great economic and ecological effect. Therefore, this achievement provides a new way for mine water conservation in shallow coal resources in western China.展开更多
A cloud-resolving model simulation of a mesoscale convective system （MCS） producing torrential rainfall is performed with the finest horizontal resolution of 444 m. It is shown that the model reproduces the observed...A cloud-resolving model simulation of a mesoscale convective system （MCS） producing torrential rainfall is performed with the finest horizontal resolution of 444 m. It is shown that the model reproduces the observed MCS, including its rainfall distribution and amounts, as well as the timing and location of leading rainbands and trailing stratiform clouds. Results show that discrete convective hot towers, shown in Vis5D at a scale of 2-5 kin, are triggered by evaporatively driven cold outflows converging with the high-θe air ahead. Then, they move rearward, with respect to the leading rainbands, to form stratiform clouds. These convective towers generate vortical tubes of opposite signs, with more intense cyclonic vorticity occurring in the leading convergence zone. The results appear to have important implications for the improvement of summertime quantitative precipitation forecasts and the understanding of vortical hot towers, as well midlevel mesoscale convective vortices.展开更多
Rapid,high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae,which are responsible for algal blooms,such as red and green tides. In this study,we successfully develop...Rapid,high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae,which are responsible for algal blooms,such as red and green tides. In this study,we successfully developed a multiplex PCR-based DNA microarray method capable of detecting nine harmful algal species simultaneously,namely A lexandrium tamarense,Gyrodinium instriatum,Heterosigma akashiwo,Karenia mikimotoi,Prorocentrum donghaiense,Prorocentrum minimum,Ulva compressa,Ulva ohnoi and Ulva prolifera. This method achieved a limit of detection(LOD) of 0.5 ng of genomic DNA(orders of magnitude of the deci-nanogram range) in the tested algae cultures. Altogether,230 field samples from ship ballast waters and seaport waters were used to evaluate the DNA microarray. The clinical sensitivity and specificity of the DNA microarray assay in detecting field samples were 96.4% and 90.9%,respectively,relative to conventional morphological methods. This indicated that this high-throughput,automatic,and specific method is well suited for the detection of algae in water samples.展开更多
The variations of the meltwater runoff draining from Kartamak Glacier in Mt. Muztag Ata in China were studied by using the measured hydrological data from 1 June to 25 August 2003. The meltwater runoff is mainly affec...The variations of the meltwater runoff draining from Kartamak Glacier in Mt. Muztag Ata in China were studied by using the measured hydrological data from 1 June to 25 August 2003. The meltwater runoff is mainly affected by ambient temperature and precipitation. Meltwater and precipitation samples were collected from 10 to 23 August 2003. Their pH, EC (electric conductivity) and the major ions (Na^+, K^+, Ca^(2+), Mg^(2+), Cl^-, NO_3^-, SO_~4^(2-)) were determined. pH values showed a positive correlation with EC values for all samples. Meltwater samples were slightly alkaline. Sulfate and calcium were the dominant anion and cation in the measured ions, respectively. All the ion concentrations had inverse relationships with runoff or water level. In order to discuss the origins of dissolved chemical substances in the glacial meltwater, a principal component analysis was carried out. The results showed that water-rock interaction determined the ion components of the meltwater.展开更多
UMhlathuze River is the main recipient of domestic sewage, industrial as well as agricultural waste from local industrial and agricultural practices. It is the effluent ＂dumping sites＂ for most human activity practi...UMhlathuze River is the main recipient of domestic sewage, industrial as well as agricultural waste from local industrial and agricultural practices. It is the effluent ＂dumping sites＂ for most human activity practices. Contamination of UMhlathuze River by agricultural and industrial developments makes communities around UMhlathuze area susceptible to potential outbreaks of water-borne illnesses as well as the risk of ingesting carcinogenic substances. In establishment of the effect of human developments on the UMhlathuze River, four different sites representing different human activities were used for sampling along the river. Temperature and pH were monitored in siitu and were found to vary between 19-21℃and 6.2-7.8, respectively. Chemical oxygen demand （COD） was found to be higher in areas affected by both industrial and agricultural activities. Spectroquadrant Pharo 300 （Merck） was used for chemical analysis of water. Agricultural waste recipient area had high concentration of phosphate, ammonia and nitrate. Parts of the river receiving effluent from treated wastewater had high sulphide, nitrate and ammonia concentrations. Industrial areas had high concentration of heavy metals （e.g., aluminium）. Microorganisms found in all sites included Escherichia coli and species of Salmonella, Shigella, Citrobacter, Serratia and Enterobacter, although their quantities differed from agricultural to industrial sites. There was a positive correlation between contamination levels and human activities which ascribe river pollution to activities around the area. Agricultural and industrial development activities practiced around UMhlathuze River have a huge contribution to the continued deterioration of the quality of water at UMhlathuze River.展开更多
There are a number of factors that contribute to heavy metal contamination in agricultural soils including deficient management of solid waste, waste water discharge, irrigation with contaminated water, and use of fer...There are a number of factors that contribute to heavy metal contamination in agricultural soils including deficient management of solid waste, waste water discharge, irrigation with contaminated water, and use of fertilizers and pesticides. The aim of this study is to estimate the sources and the levels of metals in soils of the ULB （Upper Litani Basin） that receive all mentioned factors. Soil samples were collected during the dry season from 24 sites along the Litani River flow, and 12 sites irrigated by Canal 900 withdrawn from the Qaraoun Dam along river. Metals in soils were analyzed using EDXRF （energy dispersive X-ray fluorescence） technique. Data revealed the following average levels of some heavy metals in soils with high percentage of samples exceeding the international guidelines： Mn （593 mg/kg）--67%, Ni （98 mg/kg）--96%, Cr （143 mg/kg）--92%, Hg （3.6 mg/kg）--38%, Cd （2.8 mg/kg）---25% and As （17.6 mg/kg）-84%. In canal soils： Mn （683 mg/kg）-86%, Ni （156 mg/kg）-100%, Cr （203 mg/kg） -100%, Hg （2.3 mg/kg）-25%, Cd （3.3 mg/kg）-25% and As （19.5 mg/kg）-92%. The prime source of toxic metals was due to the agricultural runoffs, beside sewage and domestic waste water discharge. Thus, the prominent findings of high levels of toxic metals （Cr, Cd, Hg and As） in soils and consequent probability in plants might induce a major health threat to consumers,展开更多
Soil water dynamics in the dominant lwo soil series （Arinic lixisol） were evaluated at the Federal University of Agriculture, Alabata, Abeokuta, Nigeria. Field capacity, infiltration and water retention characterist...Soil water dynamics in the dominant lwo soil series （Arinic lixisol） were evaluated at the Federal University of Agriculture, Alabata, Abeokuta, Nigeria. Field capacity, infiltration and water retention characteristics were evaluated in situ for a period of 161 d in the dry season for two root zone depths. Results show that the Iwo soil series has a field capacity ranging from 2.6%-5.5% at 0-45 cm and 45-90 cm root zone depths, respectively. The soil is quick draining with high infiltration rate and very poor water retention capacity confirming that the soil will require a short irrigation interval of about 2-3 d since available water for plant growth in predominantly sandy soils ranges between 2%-8%. Based on the foregoing, sprinkler irrigation is best suited for the lwo soil series, it should, however, be noted that the water application rate must be less than the infiltration rate of the soil in order to prevent surface ponding and runoff. A multivariate model relating soil moisture content with soil moisture tension and soil temperature calibrated within the study had very low model accuracy of 56% and 45% for the two root zone depths, respectively, implying the need for further studies.展开更多
The present work is aimed at assessing the water quality index （WQI） for the groundwater for Gulbarga city. The water quality index （WQI） is a mathematical instrument used to transform large quantities of water qu...The present work is aimed at assessing the water quality index （WQI） for the groundwater for Gulbarga city. The water quality index （WQI） is a mathematical instrument used to transform large quantities of water quality data into a single number which represents the water quality level. In fact, developing WQI in an area is a fundamental process in the planning of land use and water resources management. One can then compare different samples for quality on the basis of the index value of each sample. The present work relates to the development of water quality index for the study area based on the experimental results of physicochemical analysis of water samples. For calculating the WQI, the following 11 parameters have been considered, pH, TH, Ca, Mg, NO3, SO4, TDS, F, CI, K and Na. The WQI for these samples ranges from 10.40 to 155. Using developed indices, groundwater isopleth map has been prepared for study area. In the case study, the WQI map reveals that groundwater quality in two areas is extremely near to mineral water quality. Created index map provides a comprehensive picture that is easily interpretable for regional decision makers for better planning and management. The results of analysis have been used to suggest models for predicting water quality. The analysis reveals that the groundwater of the area needs some degree of treatment before consumption, and it also needs to be protected from the perils of contamination.展开更多
Water table over an arid region can be elevated to a critical level to sustain terrestrial ecosystem along the natural channel by the stream water conveyance. Estimation of water table depth and soil moisture on river...Water table over an arid region can be elevated to a critical level to sustain terrestrial ecosystem along the natural channel by the stream water conveyance. Estimation of water table depth and soil moisture on river channel profile may be reduced to a two-dimensional moving boundary problem with soil water-groundwater interaction. The two-dimensional soil water flow with stream water transferred is divided into an unsaturated vertical soil water flow and a horizontal groundwater flow. Therefore, a prediction model scheme for water table depths under the interaction between soil water and groundwater with stream water transferred is presented, which includes a vertical soil water movement model, a horizontal groundwater movement model, and an interface model. The synthetic experiments are conducted to test the sensitivities of the river elevation, horizontal conductivity, and surface flux, and the results from the experiments show the robustness of the proposed scheme under different conditions. The groundwater horizontal conductivity of the proposed scheme is also calibrated by SCE-UA method and validated by data collected at the Yingsu section in the lower reaches of the Tarim River, which shows that the model can reasonably simulate the water table depths.展开更多
基金Projects NCET-05-0480 supported by the New Century Excellent Talents in University50904063 by the National Natural Science Foundation of China+1 种基金07KF09 by the Research Fund of the State Key Laboratory of Coal Resources and Mine Safety of China University of Mining & Technology2008A003 and 2005B002 by the Scientific Research Foundation of China University of Mining & Technology
文摘In exploiting shallow coal resources in western China, conservation of water resources is often subjugated to considerations of safety and production in coal mines. In order to maintain a sustainable development in the Shenfu-Dongsheng coalfield, we propose a technology of constructing groundwater reservoirs in goafs in shallow coalfields to protect fragile ecological environments. Given the premise of safe production, we selected an appropriate goaf as the site for constructing a groundwater reservoir and used a mine water recharge technique in combination with other related techniques for effective water conservation. Then filtering and purification techniques were used to purify the mine water given the physical and chemical properties of mine water and its filling material, ,thereby greatly reducing suspended matter, calcium and other harmful ions in the water. With the potential of widely application, the research result has been successfully applied in the Daliuta coal mine, to great economic and ecological effect. Therefore, this achievement provides a new way for mine water conservation in shallow coal resources in western China.
基金supported by Jiangsu Education Science Foundation (Grant No.07KJB170065)Chinese National Science Foundation (Grant No.40775060)U.S.National Science Foundation (Grant No.ATM0758609)
文摘A cloud-resolving model simulation of a mesoscale convective system （MCS） producing torrential rainfall is performed with the finest horizontal resolution of 444 m. It is shown that the model reproduces the observed MCS, including its rainfall distribution and amounts, as well as the timing and location of leading rainbands and trailing stratiform clouds. Results show that discrete convective hot towers, shown in Vis5D at a scale of 2-5 kin, are triggered by evaporatively driven cold outflows converging with the high-θe air ahead. Then, they move rearward, with respect to the leading rainbands, to form stratiform clouds. These convective towers generate vortical tubes of opposite signs, with more intense cyclonic vorticity occurring in the leading convergence zone. The results appear to have important implications for the improvement of summertime quantitative precipitation forecasts and the understanding of vortical hot towers, as well midlevel mesoscale convective vortices.
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2012AA092001)the Science and Technology Project of Zhejiang Province(No.2013C03045-1)+2 种基金the Zhejiang Marine Biotechnology Innovation Team(No.2010R50029-12)the Natural Science Foundation of Ningbo City of China(No.2013A610168)the KC Wong Magna Fund in Ningbo University
文摘Rapid,high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae,which are responsible for algal blooms,such as red and green tides. In this study,we successfully developed a multiplex PCR-based DNA microarray method capable of detecting nine harmful algal species simultaneously,namely A lexandrium tamarense,Gyrodinium instriatum,Heterosigma akashiwo,Karenia mikimotoi,Prorocentrum donghaiense,Prorocentrum minimum,Ulva compressa,Ulva ohnoi and Ulva prolifera. This method achieved a limit of detection(LOD) of 0.5 ng of genomic DNA(orders of magnitude of the deci-nanogram range) in the tested algae cultures. Altogether,230 field samples from ship ballast waters and seaport waters were used to evaluate the DNA microarray. The clinical sensitivity and specificity of the DNA microarray assay in detecting field samples were 96.4% and 90.9%,respectively,relative to conventional morphological methods. This indicated that this high-throughput,automatic,and specific method is well suited for the detection of algae in water samples.
基金This work was supported by the National Basic Research Program of China （Grant No.2005CB422004）；the Knowledge Innovation Project of CAS of China （Grant No. KZCX3-SW-339）；the Innovative Research Team of the National Natural Science Foundation of China （Grant No. 40121101）.
文摘The variations of the meltwater runoff draining from Kartamak Glacier in Mt. Muztag Ata in China were studied by using the measured hydrological data from 1 June to 25 August 2003. The meltwater runoff is mainly affected by ambient temperature and precipitation. Meltwater and precipitation samples were collected from 10 to 23 August 2003. Their pH, EC (electric conductivity) and the major ions (Na^+, K^+, Ca^(2+), Mg^(2+), Cl^-, NO_3^-, SO_~4^(2-)) were determined. pH values showed a positive correlation with EC values for all samples. Meltwater samples were slightly alkaline. Sulfate and calcium were the dominant anion and cation in the measured ions, respectively. All the ion concentrations had inverse relationships with runoff or water level. In order to discuss the origins of dissolved chemical substances in the glacial meltwater, a principal component analysis was carried out. The results showed that water-rock interaction determined the ion components of the meltwater.
文摘UMhlathuze River is the main recipient of domestic sewage, industrial as well as agricultural waste from local industrial and agricultural practices. It is the effluent ＂dumping sites＂ for most human activity practices. Contamination of UMhlathuze River by agricultural and industrial developments makes communities around UMhlathuze area susceptible to potential outbreaks of water-borne illnesses as well as the risk of ingesting carcinogenic substances. In establishment of the effect of human developments on the UMhlathuze River, four different sites representing different human activities were used for sampling along the river. Temperature and pH were monitored in siitu and were found to vary between 19-21℃and 6.2-7.8, respectively. Chemical oxygen demand （COD） was found to be higher in areas affected by both industrial and agricultural activities. Spectroquadrant Pharo 300 （Merck） was used for chemical analysis of water. Agricultural waste recipient area had high concentration of phosphate, ammonia and nitrate. Parts of the river receiving effluent from treated wastewater had high sulphide, nitrate and ammonia concentrations. Industrial areas had high concentration of heavy metals （e.g., aluminium）. Microorganisms found in all sites included Escherichia coli and species of Salmonella, Shigella, Citrobacter, Serratia and Enterobacter, although their quantities differed from agricultural to industrial sites. There was a positive correlation between contamination levels and human activities which ascribe river pollution to activities around the area. Agricultural and industrial development activities practiced around UMhlathuze River have a huge contribution to the continued deterioration of the quality of water at UMhlathuze River.
文摘There are a number of factors that contribute to heavy metal contamination in agricultural soils including deficient management of solid waste, waste water discharge, irrigation with contaminated water, and use of fertilizers and pesticides. The aim of this study is to estimate the sources and the levels of metals in soils of the ULB （Upper Litani Basin） that receive all mentioned factors. Soil samples were collected during the dry season from 24 sites along the Litani River flow, and 12 sites irrigated by Canal 900 withdrawn from the Qaraoun Dam along river. Metals in soils were analyzed using EDXRF （energy dispersive X-ray fluorescence） technique. Data revealed the following average levels of some heavy metals in soils with high percentage of samples exceeding the international guidelines： Mn （593 mg/kg）--67%, Ni （98 mg/kg）--96%, Cr （143 mg/kg）--92%, Hg （3.6 mg/kg）--38%, Cd （2.8 mg/kg）---25% and As （17.6 mg/kg）-84%. In canal soils： Mn （683 mg/kg）-86%, Ni （156 mg/kg）-100%, Cr （203 mg/kg） -100%, Hg （2.3 mg/kg）-25%, Cd （3.3 mg/kg）-25% and As （19.5 mg/kg）-92%. The prime source of toxic metals was due to the agricultural runoffs, beside sewage and domestic waste water discharge. Thus, the prominent findings of high levels of toxic metals （Cr, Cd, Hg and As） in soils and consequent probability in plants might induce a major health threat to consumers,
文摘Soil water dynamics in the dominant lwo soil series （Arinic lixisol） were evaluated at the Federal University of Agriculture, Alabata, Abeokuta, Nigeria. Field capacity, infiltration and water retention characteristics were evaluated in situ for a period of 161 d in the dry season for two root zone depths. Results show that the Iwo soil series has a field capacity ranging from 2.6%-5.5% at 0-45 cm and 45-90 cm root zone depths, respectively. The soil is quick draining with high infiltration rate and very poor water retention capacity confirming that the soil will require a short irrigation interval of about 2-3 d since available water for plant growth in predominantly sandy soils ranges between 2%-8%. Based on the foregoing, sprinkler irrigation is best suited for the lwo soil series, it should, however, be noted that the water application rate must be less than the infiltration rate of the soil in order to prevent surface ponding and runoff. A multivariate model relating soil moisture content with soil moisture tension and soil temperature calibrated within the study had very low model accuracy of 56% and 45% for the two root zone depths, respectively, implying the need for further studies.
文摘The present work is aimed at assessing the water quality index （WQI） for the groundwater for Gulbarga city. The water quality index （WQI） is a mathematical instrument used to transform large quantities of water quality data into a single number which represents the water quality level. In fact, developing WQI in an area is a fundamental process in the planning of land use and water resources management. One can then compare different samples for quality on the basis of the index value of each sample. The present work relates to the development of water quality index for the study area based on the experimental results of physicochemical analysis of water samples. For calculating the WQI, the following 11 parameters have been considered, pH, TH, Ca, Mg, NO3, SO4, TDS, F, CI, K and Na. The WQI for these samples ranges from 10.40 to 155. Using developed indices, groundwater isopleth map has been prepared for study area. In the case study, the WQI map reveals that groundwater quality in two areas is extremely near to mineral water quality. Created index map provides a comprehensive picture that is easily interpretable for regional decision makers for better planning and management. The results of analysis have been used to suggest models for predicting water quality. The analysis reveals that the groundwater of the area needs some degree of treatment before consumption, and it also needs to be protected from the perils of contamination.
基金supported by National Basic Research Program (Grant Nos. 2010CB428403, 2010CB951001)Chinese COPES Project (Grant No. GYHY200706005)National High Technology Research and Development Program of China (Grant No. 2009AA12Z129)
文摘Water table over an arid region can be elevated to a critical level to sustain terrestrial ecosystem along the natural channel by the stream water conveyance. Estimation of water table depth and soil moisture on river channel profile may be reduced to a two-dimensional moving boundary problem with soil water-groundwater interaction. The two-dimensional soil water flow with stream water transferred is divided into an unsaturated vertical soil water flow and a horizontal groundwater flow. Therefore, a prediction model scheme for water table depths under the interaction between soil water and groundwater with stream water transferred is presented, which includes a vertical soil water movement model, a horizontal groundwater movement model, and an interface model. The synthetic experiments are conducted to test the sensitivities of the river elevation, horizontal conductivity, and surface flux, and the results from the experiments show the robustness of the proposed scheme under different conditions. The groundwater horizontal conductivity of the proposed scheme is also calibrated by SCE-UA method and validated by data collected at the Yingsu section in the lower reaches of the Tarim River, which shows that the model can reasonably simulate the water table depths.
