Water samples collected from early March 2001 to the end of April 2002 at the branch of Pearl River around the Guangzhou City were analyzed for its micro-polluted characteristics. The coagulation behavior of polyalumi...Water samples collected from early March 2001 to the end of April 2002 at the branch of Pearl River around the Guangzhou City were analyzed for its micro-polluted characteristics. The coagulation behavior of polyaluminum chlorides(PACls) was then examined focusing on the effect of primary water quality and speciation distribution. The results showed that PACls exhibit better coagulation efficiency than alum in accordance with the different speciation. The turbidity removal property of PACls is evidently better than alum at low dosage. While in neutral zone(about 6.5—7.5), the turbidity removal of PACls decreases owing to the restabilization of particles at higher dosage. The organic matters in raw water exhibit marked influence on coagulation. In acidic zone, organic matters complex with polymer species and promote the formation of flocs. With an increase in pH, the complexation of organics with polymer species gradually decreases, and the removal of organics mainly depends on adsorption. The effect is evidently improved with the raise of B value.展开更多
A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile ...A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD.展开更多
[ Objective] The study aims to resolve water resource problem availably. [ Method] On the basis of wetland self-purification capacity, Yanshan River water was purified by Xixi Wetland, and the feasibility of using tre...[ Objective] The study aims to resolve water resource problem availably. [ Method] On the basis of wetland self-purification capacity, Yanshan River water was purified by Xixi Wetland, and the feasibility of using treated Yanshan River water for urban greening and watering road was analyzed. [Result] Compared with direct utilization of tap water, it is more economic to recycle Yanshan River water purified by Xixi Wetland for urban greening and watering read, with obvious economic, ecological and social benefits, so it is an effective method to address shortage of water resources and is worth spreading. [ Conclusion] It is feasible to use Yanshan River water purified by Xixi Wetland for urban greening and watering read.展开更多
Total dissolved organic carbon (TOC), number of colony forming units (CFU), and total direct count (TDC) were compared to the biodegradation of aniline and the number of potential degraders in water samples from head ...Total dissolved organic carbon (TOC), number of colony forming units (CFU), and total direct count (TDC) were compared to the biodegradation of aniline and the number of potential degraders in water samples from head waters to down stream of the Ina River and several other sites of rivers traversing Osaka city. The results indicate that aniline degrading populations of these various microbial communities exhibit different activities probably depending on the extent of adaptation to pollutants to which the microbes are exposed. The number of aniline degraders found in river water samples was in agreement with other parameters which were used to demonstrate the degree of pollution in river water even though higher biodegradability was evident in waters which show comparatively low TOC and CFU. These results suggest that biodegradation of aniline and enumeration of its potential degraders may serve as valuable indicators for the assessment of pollution in river waters.展开更多
Estimating the impact of mountain landscape on hydrology or water balance is essential for the sus- tainable development strategies of water resources. Specifically, understanding how the change of each landscape infl...Estimating the impact of mountain landscape on hydrology or water balance is essential for the sus- tainable development strategies of water resources. Specifically, understanding how the change of each landscape influences hydrological components will greatly improve the predictability of hydrological responses to mountain landscape changes and thus can help the government make sounder decisions. In the paper, we used the VIC (Variable Infiltration Capacity) model to conduct hydrological modeling in the upper Heihe River watershed, along with a frozen-soil module and a glacier melting module to improve the simulation. The improved model performed satisfactorily. We concluded that there are differences in the runoff generation of mountain landscape both in space and time. About 50% of the total runoff at the catchment outlet were generated in mid-mountain zone (2,900-4,000 m asl), and water was mainly consumed in low mountain region (1,700-2,900 m asl) because of the higher requirements of trees and grasses. The runoff coefficient was 0.37 in the upper Heihe River watershed. Barren landscape produced the largest runoff yields (52.46% of the total runoff) in the upper Heihe River watershed, fol- lowed by grassland (34.15%), shrub (9.02%), glacier (3.57%), and forest (0.49%). In order to simulate the impact of landscape change on hydrological components, three landscape change scenarios were designed in the study. Scenario 1, 2 and 3 were to convert all shady slope landscapes at 2,000-3,300 m, 2,000-3,700 m, and 2,000-4,000 m asl respectively to forest lands, with forest coverage rate increased to 12.4%, 28.5% and 42.0%, respectively. The runoff at the catchment outlet correspondingly declined by 3.5%, 13.1% and 24.2% under the three scenarios. The forest landscape is very important in water conservation as it reduced the flood peak and increased the base flow. The mountains as "water towers" play important roles in water resources generation and the impact of mountain landscapes on hydrology is significant.展开更多
The efficiencies of two types of constructed wetlands for the treatment of low-concentration polluted eutrophic land- scape river water were studied in the western section of the Qingyuan River at the Minhang campus o...The efficiencies of two types of constructed wetlands for the treatment of low-concentration polluted eutrophic land- scape river water were studied in the western section of the Qingyuan River at the Minhang campus of Shanghai Jiaotong University.The first wetland was a single-stage system using gravel as a filtration medium,and the second was a three- stage system filled with combinations of gravel,zeolite,and fly ash.Results from parallel operations of the wetlands showed that the three-stage constructed wetland could remove organics,nitrogen, and phosphorus successfully.At the same time,it could also decrease ammoniacal odour in the effluent.Compared to the single-stage constructed wetland,it had better nutrient removal efficiencies with a higher removal of 19.37%-65.27% for total phosphorus (TP) and 21.56%- 62.94% for total nitrogen (TN),respectively,during the operation period of 14 weeks.In terms of removal of chemical oxygen demand (COD), turbidity,and blue-green algae,these two wetland systems had equivalent performances.It was also found that in the western section of the test river,in which the two constructed wetlands were located, the water quality was much better than that in the eastern and middle sections without constructed wetland because COD,TN, and TP were all in a relatively lower level and the eutrophication could be prevented completely in the western section.展开更多
The chemical composition of Wujiang River water represents that of river water from the typical carbonate areas. Its hydrogeochemical characteristics are different from those of global major rivers. The Wujiang River ...The chemical composition of Wujiang River water represents that of river water from the typical carbonate areas. Its hydrogeochemical characteristics are different from those of global major rivers. The Wujiang River and its tributaries have high total dissolved solid concentrations, with Ca\+\{2+\} and HCO\+-\-3 being dominant, Mg\+\{2+\} and SO\+\{2-\}\-4 coming next. Both Na\+++K\++ and Cl\+-+Si account for 5%-10% of the total cations and anions, respectively. These general features show the chemical composition of river water is largely controlled by carbonate weathering, with the impact of silicate and evaporate weathering being of less importance. Production activity, mining practice and industrial pollution also have some influence on the chemical composition of river water.展开更多
With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas ...With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas River watershed. The results showed that the soil moisture data from all soil layers exhibited a normal distribution, with average values of 14.08%-21.55%. Geostatistical analysis revealed that the content of soil moisture had a moder- ate spatial autocorrelation with the ratios of nugget/sill ranging from 0.500 to 0.718, which implies that the spatial pattern of soil moisture is influenced by the combined effects of structural factors and random factors. Remarkable spatial distributions with stripped and mottled features were found for soil moisture in all different soil layers. The landform and crop planting had a relatively big influence on the spatial distribution of soil moisture; total soil salinity was high in east but low in west, and non-salinized soil and lightly salinized soil appeared at the northwest and southwest of the study area. Under the effect of reservoir leakage, the heavily salinized soils are widely distributed in the middle of the study area. The areas of the non-salinized and lightly salinized soils decreased gradually with soil depth increment, which is contrary to the case for saline soils that reached a maximum of 245.67 km2 at the layer of 50-70 cm. The types of soil salinization in Manas River watershed were classified into four classes: the sulfate, chloride-sulfate, sulfate-chloride and chloride. The sulfate salinized soil is most widely distributed in the surface layer. The areas of chloride-sulfate, sulfate-chloride, and chloride salinized soils increased gradually along with the increment of soil depth; the variation range of the average values of soil organic matter content was be- tween 7.48%-11.33%. The ratios of nugget/sill reduced gradually from 0.698 to 0.299 with soil depth increment, which shows that the content of soil organic matter has a moderate spatial autocorrelation. The soil organic matter in all soil layers met normal distribution after logarithmic transformation. The spatial distribution patterns of soil or- ganic matter and soil moisture were similar; the areas with high organic matter contents were mainly distributed in the south of the study area, with the lowest contents in the middle.展开更多
River water plays a key role in human health, and in social and economic development, and is often affected by both natural factors and human activities. An in-depth understanding of the role of these factors can help...River water plays a key role in human health, and in social and economic development, and is often affected by both natural factors and human activities. An in-depth understanding of the role of these factors can help in developing an effective catchment management strategy to protect precious water resources. This study analyzed river water quality, patterns of terrestrial and riparian ecosystems, intensity of agricultural activities, industrial structure, and spatial distribution of pollutant emissions in the Haihe River Basin in China for the year of 2010, identifying the variables that have the greatest impact on river water quality. The area percentage of farmland in study area, the percentage of natural vegetation cover in the 1000-m riparian zone, rural population density, industrial Gross Domestic Product(GDP)/km^2, and industrial amino nitrogen emissions were all significantly correlated with river water quality(P < 0.05). Farming had the largest impact on river water quality, explaining 43.0% of the water quality variance, followed by the coverage of natural vegetation in the 1000-m riparian zone, which explained 36.2% of the water quality variance. Industrial amino nitrogen emissions intensity and rural population density explained 31.6% and 31.4% of the water quality variance, respectively, while industrial GDP/km^2 explained 26.6%. Together, these five indicators explained 67.3% of the total variance in water quality. Consequently, water environmental management of the Haihe River Basin should focus on adjusting agricultural activities, conserving riparian vegetation, and reducing industrial pollutant emissions by optimizing industrial structure. The results demonstrate how human activities drive the spatial pattern changes of river water quality, and they can provide reference for developing land use guidelines and for prioritizing management practices to maintain stream water quality in a large river basin.展开更多
This study aimed at using nine ecological parameters in evaluating the quality of the Tigris River for public usage, by choosing five sampling sites along the river in Baghdad area. These parameters included temperatu...This study aimed at using nine ecological parameters in evaluating the quality of the Tigris River for public usage, by choosing five sampling sites along the river in Baghdad area. These parameters included temperature, pH, the saturated ratio by dissolved oxygen (%sat), biological oxygen demand (BOD5), nitrate (NO3?1), phosphate (PO4?3), fecal coliform (FC) turbidity and total dissolved solids (TDS), and these parameters were used for calculating overall water quality index in the Tigris River at study area. The results showed high values of turbidity and TDS, as well as high count of FC in all study stations, while other studied parameters were within permissible limit defined by world health organization and Iraqi criteria. The results of the overall water quality index indicated that the Tigris River was in class medium, therefore the Tigris River water in study area is relatively not safe for direct domestic use in all seasons.展开更多
In the present study, trace elements present in the river waters of Sarzhal and Akzhar region were measured using inductively coupled plasma mass spectrometry (ICP-MS). The reason for monitoring trace elements at thos...In the present study, trace elements present in the river waters of Sarzhal and Akzhar region were measured using inductively coupled plasma mass spectrometry (ICP-MS). The reason for monitoring trace elements at those two locations is to verify water quality. The village of Sarzhal is situated in an area that has been affected by weapon testing and continues to receive inputs of contaminants (including radionuclides). The concentrations of trace elements in the river water of Sarzhal and Akzhar villages were generally found to be within allowable levels. However, the concentrations of Na 251.56 mg/l, Cr 3.26 μg/l, P 64.56 μg/l and Se 18.162 μg/l in the river of Akzhar were found to be higher than the maximum allowable concentrations (MAC). In Sarzhal, the level of Al 6.66 mg/l, Cr 5.04 μg/l and P 13.44 μg/l exceeded the MAC values.展开更多
Based on the isotope analysis result of water samples in the 18 sections of the Yellow River, the variation of δ 18 O and δD have been analyzed. From near the source to the entrance to the sea, the Yellow River has ...Based on the isotope analysis result of water samples in the 18 sections of the Yellow River, the variation of δ 18 O and δD have been analyzed. From near the source to the entrance to the sea, the Yellow River has a general trend that the ratios of the stable isotope increase progressively; The main factors affecting the isotopes in the river water are mixing of external water bodies,evaporation and others; In the river segment between Lanzhou and Baotou and in lower reaches, the extent of the evaporation effect on the isotope fractionation from the river water surface is limited but the evaporation from the irrigated river water and the return flow is one of the main factors affecting the isotopes in river water.展开更多
The measurements for the quality of the water were made at eight stations of Adügüzel Dam, Yenice Regulator, Sarayköy Bridge, Feslek Regulator, Yenipazar Bridge, Aydιn Bridge, Koçarlι Bridg...The measurements for the quality of the water were made at eight stations of Adügüzel Dam, Yenice Regulator, Sarayköy Bridge, Feslek Regulator, Yenipazar Bridge, Aydιn Bridge, Koçarlι Bridge, Söke Regulator located at the Buyuk Menderes River, Turkey. The study was conducted for the period between 2000-2013 for the months of February, April, June, August, October and December. The results received were analyzed for temperature, pH, EC, Cl<sup>-</sup>, Na, Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup>, , TDS, TH and SS aquaculture. The results of the analyses revealed that although the water pollution in the river showed variations throughout the year, in fact the samples obtained at various locations displayed high levels of pollutants. The “Regulation on Turkish Water Pollution Control” was made use of in classifying the parameters of the water in this study. These parameters were compared with the WHO Guidelines and TS-266. Among the 8 Dams that were included in the study, the best quality of water was measured in the Adügüzel Dam, which gave the lowest values;and the levels were measured to be higher in the Saraykoy Station than those of the other dams. There was a severe drought in Menderes Basin in 2007, and therefore the highest annual values were measured for the year 2007. In those years, the levels of the irrigation water decreased as low as 4255 m<sup>3</sup>/ha. The SPSS 21 Statistical Analysis Program was made use of in analyzing the data of the study. The One-Way Anova and Tukey Multiple Comparison tests were also used for the analyses of the data as well. The p < 0.05 level was accepted as being significant in the analyses. The distribution of the data was performed by using the Box-plot Graphs. Furthermore, the effects on fish species and the pollution in Büyük Menderes River were also examined in the study.展开更多
The authors demonstrate the importance of the simulation of the water quantity exchange between river water and groundwater to a better understanding of the hydrologic relations between a river and nearby aquifer wher...The authors demonstrate the importance of the simulation of the water quantity exchange between river water and groundwater to a better understanding of the hydrologic relations between a river and nearby aquifer where groundwater is pumped extensively but only seasonally. And MODFLOW is used to design the stream aquifer model in which the pumpage of more than 1000 wells was simulated. The river gaining and river losing processes were analyzed. Simulation results suggest that continuation of over extraction of groundwater will gradually increase the depletion volume in the river year after year and more depletion will occur in later years. The exchange manner between groundwater and the Platte River differs from place to place. The Platte River loses water to the adjacent aquifer in the west part of the study area, and gains water from the adjacent aquifer in the east part of the study area.展开更多
文摘Water samples collected from early March 2001 to the end of April 2002 at the branch of Pearl River around the Guangzhou City were analyzed for its micro-polluted characteristics. The coagulation behavior of polyaluminum chlorides(PACls) was then examined focusing on the effect of primary water quality and speciation distribution. The results showed that PACls exhibit better coagulation efficiency than alum in accordance with the different speciation. The turbidity removal property of PACls is evidently better than alum at low dosage. While in neutral zone(about 6.5—7.5), the turbidity removal of PACls decreases owing to the restabilization of particles at higher dosage. The organic matters in raw water exhibit marked influence on coagulation. In acidic zone, organic matters complex with polymer species and promote the formation of flocs. With an increase in pH, the complexation of organics with polymer species gradually decreases, and the removal of organics mainly depends on adsorption. The effect is evidently improved with the raise of B value.
文摘A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD.
基金Supported by the Project for Science and Technology Innovation Team of Zhejiang Province,China
文摘[ Objective] The study aims to resolve water resource problem availably. [ Method] On the basis of wetland self-purification capacity, Yanshan River water was purified by Xixi Wetland, and the feasibility of using treated Yanshan River water for urban greening and watering road was analyzed. [Result] Compared with direct utilization of tap water, it is more economic to recycle Yanshan River water purified by Xixi Wetland for urban greening and watering read, with obvious economic, ecological and social benefits, so it is an effective method to address shortage of water resources and is worth spreading. [ Conclusion] It is feasible to use Yanshan River water purified by Xixi Wetland for urban greening and watering read.
文摘Total dissolved organic carbon (TOC), number of colony forming units (CFU), and total direct count (TDC) were compared to the biodegradation of aniline and the number of potential degraders in water samples from head waters to down stream of the Ina River and several other sites of rivers traversing Osaka city. The results indicate that aniline degrading populations of these various microbial communities exhibit different activities probably depending on the extent of adaptation to pollutants to which the microbes are exposed. The number of aniline degraders found in river water samples was in agreement with other parameters which were used to demonstrate the degree of pollution in river water even though higher biodegradability was evident in waters which show comparatively low TOC and CFU. These results suggest that biodegradation of aniline and enumeration of its potential degraders may serve as valuable indicators for the assessment of pollution in river waters.
基金funded by the National Natural Science Foundation of China (41130638)the key innovation project of the Chinese Academy of Sciences (KZCX2-YW-QN310)the National Science and Technology Support Program (2013BAB05B03)
文摘Estimating the impact of mountain landscape on hydrology or water balance is essential for the sus- tainable development strategies of water resources. Specifically, understanding how the change of each landscape influences hydrological components will greatly improve the predictability of hydrological responses to mountain landscape changes and thus can help the government make sounder decisions. In the paper, we used the VIC (Variable Infiltration Capacity) model to conduct hydrological modeling in the upper Heihe River watershed, along with a frozen-soil module and a glacier melting module to improve the simulation. The improved model performed satisfactorily. We concluded that there are differences in the runoff generation of mountain landscape both in space and time. About 50% of the total runoff at the catchment outlet were generated in mid-mountain zone (2,900-4,000 m asl), and water was mainly consumed in low mountain region (1,700-2,900 m asl) because of the higher requirements of trees and grasses. The runoff coefficient was 0.37 in the upper Heihe River watershed. Barren landscape produced the largest runoff yields (52.46% of the total runoff) in the upper Heihe River watershed, fol- lowed by grassland (34.15%), shrub (9.02%), glacier (3.57%), and forest (0.49%). In order to simulate the impact of landscape change on hydrological components, three landscape change scenarios were designed in the study. Scenario 1, 2 and 3 were to convert all shady slope landscapes at 2,000-3,300 m, 2,000-3,700 m, and 2,000-4,000 m asl respectively to forest lands, with forest coverage rate increased to 12.4%, 28.5% and 42.0%, respectively. The runoff at the catchment outlet correspondingly declined by 3.5%, 13.1% and 24.2% under the three scenarios. The forest landscape is very important in water conservation as it reduced the flood peak and increased the base flow. The mountains as "water towers" play important roles in water resources generation and the impact of mountain landscapes on hydrology is significant.
基金the National High Technology Research and Development Program of China (863 Program)(No.2002AA601013).
文摘The efficiencies of two types of constructed wetlands for the treatment of low-concentration polluted eutrophic land- scape river water were studied in the western section of the Qingyuan River at the Minhang campus of Shanghai Jiaotong University.The first wetland was a single-stage system using gravel as a filtration medium,and the second was a three- stage system filled with combinations of gravel,zeolite,and fly ash.Results from parallel operations of the wetlands showed that the three-stage constructed wetland could remove organics,nitrogen, and phosphorus successfully.At the same time,it could also decrease ammoniacal odour in the effluent.Compared to the single-stage constructed wetland,it had better nutrient removal efficiencies with a higher removal of 19.37%-65.27% for total phosphorus (TP) and 21.56%- 62.94% for total nitrogen (TN),respectively,during the operation period of 14 weeks.In terms of removal of chemical oxygen demand (COD), turbidity,and blue-green algae,these two wetland systems had equivalent performances.It was also found that in the western section of the test river,in which the two constructed wetlands were located, the water quality was much better than that in the eastern and middle sections without constructed wetland because COD,TN, and TP were all in a relatively lower level and the eutrophication could be prevented completely in the western section.
基金GrantedjointlybytheStateOutstandingYouthFoundation (No .496 2 5 30 4) ,theFoundationoftheChineseAcademyofSci ences (No .KZ95 2
文摘The chemical composition of Wujiang River water represents that of river water from the typical carbonate areas. Its hydrogeochemical characteristics are different from those of global major rivers. The Wujiang River and its tributaries have high total dissolved solid concentrations, with Ca\+\{2+\} and HCO\+-\-3 being dominant, Mg\+\{2+\} and SO\+\{2-\}\-4 coming next. Both Na\+++K\++ and Cl\+-+Si account for 5%-10% of the total cations and anions, respectively. These general features show the chemical composition of river water is largely controlled by carbonate weathering, with the impact of silicate and evaporate weathering being of less importance. Production activity, mining practice and industrial pollution also have some influence on the chemical composition of river water.
基金funded by the National Basic Research Program of China(2009CB825101)the National Natural Science Foundation of China(41071139)
文摘With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas River watershed. The results showed that the soil moisture data from all soil layers exhibited a normal distribution, with average values of 14.08%-21.55%. Geostatistical analysis revealed that the content of soil moisture had a moder- ate spatial autocorrelation with the ratios of nugget/sill ranging from 0.500 to 0.718, which implies that the spatial pattern of soil moisture is influenced by the combined effects of structural factors and random factors. Remarkable spatial distributions with stripped and mottled features were found for soil moisture in all different soil layers. The landform and crop planting had a relatively big influence on the spatial distribution of soil moisture; total soil salinity was high in east but low in west, and non-salinized soil and lightly salinized soil appeared at the northwest and southwest of the study area. Under the effect of reservoir leakage, the heavily salinized soils are widely distributed in the middle of the study area. The areas of the non-salinized and lightly salinized soils decreased gradually with soil depth increment, which is contrary to the case for saline soils that reached a maximum of 245.67 km2 at the layer of 50-70 cm. The types of soil salinization in Manas River watershed were classified into four classes: the sulfate, chloride-sulfate, sulfate-chloride and chloride. The sulfate salinized soil is most widely distributed in the surface layer. The areas of chloride-sulfate, sulfate-chloride, and chloride salinized soils increased gradually along with the increment of soil depth; the variation range of the average values of soil organic matter content was be- tween 7.48%-11.33%. The ratios of nugget/sill reduced gradually from 0.698 to 0.299 with soil depth increment, which shows that the content of soil organic matter has a moderate spatial autocorrelation. The soil organic matter in all soil layers met normal distribution after logarithmic transformation. The spatial distribution patterns of soil or- ganic matter and soil moisture were similar; the areas with high organic matter contents were mainly distributed in the south of the study area, with the lowest contents in the middle.
基金Under the auspices of National Natural Science Foundation of China(No.41371538)Independent Project of State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences(No.SKLURE2008-1-02)
文摘River water plays a key role in human health, and in social and economic development, and is often affected by both natural factors and human activities. An in-depth understanding of the role of these factors can help in developing an effective catchment management strategy to protect precious water resources. This study analyzed river water quality, patterns of terrestrial and riparian ecosystems, intensity of agricultural activities, industrial structure, and spatial distribution of pollutant emissions in the Haihe River Basin in China for the year of 2010, identifying the variables that have the greatest impact on river water quality. The area percentage of farmland in study area, the percentage of natural vegetation cover in the 1000-m riparian zone, rural population density, industrial Gross Domestic Product(GDP)/km^2, and industrial amino nitrogen emissions were all significantly correlated with river water quality(P < 0.05). Farming had the largest impact on river water quality, explaining 43.0% of the water quality variance, followed by the coverage of natural vegetation in the 1000-m riparian zone, which explained 36.2% of the water quality variance. Industrial amino nitrogen emissions intensity and rural population density explained 31.6% and 31.4% of the water quality variance, respectively, while industrial GDP/km^2 explained 26.6%. Together, these five indicators explained 67.3% of the total variance in water quality. Consequently, water environmental management of the Haihe River Basin should focus on adjusting agricultural activities, conserving riparian vegetation, and reducing industrial pollutant emissions by optimizing industrial structure. The results demonstrate how human activities drive the spatial pattern changes of river water quality, and they can provide reference for developing land use guidelines and for prioritizing management practices to maintain stream water quality in a large river basin.
文摘This study aimed at using nine ecological parameters in evaluating the quality of the Tigris River for public usage, by choosing five sampling sites along the river in Baghdad area. These parameters included temperature, pH, the saturated ratio by dissolved oxygen (%sat), biological oxygen demand (BOD5), nitrate (NO3?1), phosphate (PO4?3), fecal coliform (FC) turbidity and total dissolved solids (TDS), and these parameters were used for calculating overall water quality index in the Tigris River at study area. The results showed high values of turbidity and TDS, as well as high count of FC in all study stations, while other studied parameters were within permissible limit defined by world health organization and Iraqi criteria. The results of the overall water quality index indicated that the Tigris River was in class medium, therefore the Tigris River water in study area is relatively not safe for direct domestic use in all seasons.
文摘In the present study, trace elements present in the river waters of Sarzhal and Akzhar region were measured using inductively coupled plasma mass spectrometry (ICP-MS). The reason for monitoring trace elements at those two locations is to verify water quality. The village of Sarzhal is situated in an area that has been affected by weapon testing and continues to receive inputs of contaminants (including radionuclides). The concentrations of trace elements in the river water of Sarzhal and Akzhar villages were generally found to be within allowable levels. However, the concentrations of Na 251.56 mg/l, Cr 3.26 μg/l, P 64.56 μg/l and Se 18.162 μg/l in the river of Akzhar were found to be higher than the maximum allowable concentrations (MAC). In Sarzhal, the level of Al 6.66 mg/l, Cr 5.04 μg/l and P 13.44 μg/l exceeded the MAC values.
文摘Based on the isotope analysis result of water samples in the 18 sections of the Yellow River, the variation of δ 18 O and δD have been analyzed. From near the source to the entrance to the sea, the Yellow River has a general trend that the ratios of the stable isotope increase progressively; The main factors affecting the isotopes in the river water are mixing of external water bodies,evaporation and others; In the river segment between Lanzhou and Baotou and in lower reaches, the extent of the evaporation effect on the isotope fractionation from the river water surface is limited but the evaporation from the irrigated river water and the return flow is one of the main factors affecting the isotopes in river water.
文摘The measurements for the quality of the water were made at eight stations of Adügüzel Dam, Yenice Regulator, Sarayköy Bridge, Feslek Regulator, Yenipazar Bridge, Aydιn Bridge, Koçarlι Bridge, Söke Regulator located at the Buyuk Menderes River, Turkey. The study was conducted for the period between 2000-2013 for the months of February, April, June, August, October and December. The results received were analyzed for temperature, pH, EC, Cl<sup>-</sup>, Na, Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup>, , TDS, TH and SS aquaculture. The results of the analyses revealed that although the water pollution in the river showed variations throughout the year, in fact the samples obtained at various locations displayed high levels of pollutants. The “Regulation on Turkish Water Pollution Control” was made use of in classifying the parameters of the water in this study. These parameters were compared with the WHO Guidelines and TS-266. Among the 8 Dams that were included in the study, the best quality of water was measured in the Adügüzel Dam, which gave the lowest values;and the levels were measured to be higher in the Saraykoy Station than those of the other dams. There was a severe drought in Menderes Basin in 2007, and therefore the highest annual values were measured for the year 2007. In those years, the levels of the irrigation water decreased as low as 4255 m<sup>3</sup>/ha. The SPSS 21 Statistical Analysis Program was made use of in analyzing the data of the study. The One-Way Anova and Tukey Multiple Comparison tests were also used for the analyses of the data as well. The p < 0.05 level was accepted as being significant in the analyses. The distribution of the data was performed by using the Box-plot Graphs. Furthermore, the effects on fish species and the pollution in Büyük Menderes River were also examined in the study.
基金UnitedStateGeologicalSurveyGrant(No.1 4 34 HQ 96 GR 0 2 683)
文摘The authors demonstrate the importance of the simulation of the water quantity exchange between river water and groundwater to a better understanding of the hydrologic relations between a river and nearby aquifer where groundwater is pumped extensively but only seasonally. And MODFLOW is used to design the stream aquifer model in which the pumpage of more than 1000 wells was simulated. The river gaining and river losing processes were analyzed. Simulation results suggest that continuation of over extraction of groundwater will gradually increase the depletion volume in the river year after year and more depletion will occur in later years. The exchange manner between groundwater and the Platte River differs from place to place. The Platte River loses water to the adjacent aquifer in the west part of the study area, and gains water from the adjacent aquifer in the east part of the study area.