期刊文献+
共找到3,352篇文章
< 1 2 168 >
每页显示 20 50 100
Surface Water Quality Profiling Using Physicochemical Parameters in Open Defecation Free and Non-Open Defecation Free Local Government Areas in Benue State, Nigeria
1
作者 Moses T. Asoo Celestine U. Aguoru +1 位作者 Innocent O. Ogbonna Hyacinth O.A. Oluma 《Open Journal of Modern Hydrology》 CAS 2024年第3期174-191,共18页
Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/L), SO4 (0.77 ... Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/L), SO4 (0.77 mg/L), Na (28.72 mg/L), Ca (28.94 mg/L), Mg (17.50 mg/L), Cl (11.65 mg/L), TSS (6.27 mg/L), TDS (104.23 mg/L), BOD (2.83 mg/L) and F (0.87 mg/L) were below WHO standards irrespective of their defecation status. The values for electrical conductivity (EC) (2770.50 µs/cm, turbidity (481.24 NTU), dissolved oxygen (DO) (5.32 mg/L), chemical oxygen demand (COD) (445.50 mg/L), K (125.06 mg/L), PO4 (0.78 mg/L) and Fe (0.57 mg/L) were above the WHO limits for safe water. Higher EC and COD values obtained in the study is evidence of pollution of the water sources by organic matter. 展开更多
关键词 Open Defecation Surface water water quality standard Physicochemical Parameters
下载PDF
Implications of Dynamic Interactions between Meteorological Patterns and Surface Water Quality on Environmental Health—A Case Study of the Nairobi River
2
作者 Haron Safari Hongbin Chen +1 位作者 Edwin Kipkirui Duncan Mbuge 《Journal of Geoscience and Environment Protection》 2024年第5期113-146,共34页
Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and wa... Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and water quality parameters in Nairobi City, focusing on the impacts of rainfall and temperature on surface water quality. Data from multiple sources, including the Water Resources Authority, Nairobi Water and Sewerage Company, and the World Bank’s Climate Change Knowledge Portal, were analyzed to assess the relationships between meteorological variables (rainfall and temperature) and water quality parameters (such as electroconductivity, biochemical oxygen demand, chloride, and pH). The analysis reveals varying impacts of rainfall and temperature on different water quality parameters. While parameters like iron and pH show strong relationships with both rainfall and temperature, others such as ammonia and nitrate exhibit moderate relationships. Additionally, the study highlights the influence of runoff, urbanization, and industrial activities on water quality, emphasizing the need for holistic management approaches. Recommendations encompass the establishment of annual publications on Nairobi River water quality, online accessibility of water quality data, development of hydrological models, spatial analysis, and fostering cross-disciplinary research collaborations. Implementing these recommendations can enhance water quality management practices, mitigate risks, and safeguard environmental integrity in Nairobi City. 展开更多
关键词 water quality Meteorological Conditions urban Environment Environmental Health NAIROBI water quality Parameters
下载PDF
Anthropogenic disturbance of aquatic biodiversity and water quality of an urban river in Penang, Malaysia
3
作者 Nur Azalina Suzianti Feisal Noor Haziqah Kamaludin +4 位作者 Muhammad Firdaus Abdullah Sani Dayang Khairulnisa Awang Ahmad Mohd Azwan Ahmad Nur Faiza Abdul Razak Tengku Nilam Baizura Tengku Ibrahim 《Water Science and Engineering》 EI CAS CSCD 2023年第3期234-242,共9页
Malaysia's rapid economic and demographic development have placed negative pressure on its water supplies and the quality of the Juru River, which is close to the nation's capital and its major source of water... Malaysia's rapid economic and demographic development have placed negative pressure on its water supplies and the quality of the Juru River, which is close to the nation's capital and its major source of water. Healthy aquatic ecosystems are supported by physicochemical properties and biological diversity. This study evaluated the anthropogenic impacts on aquatic biodiversity, especially plankton, fish, and macrobenthos, as well as the water quality of the Juru River in the Penang area. Aquatic biodiversity and river water parameters were collected from ten sampling stations along the Juru River. Seven variables were used to assess the physicochemical environment: pH, temperature, total suspended solids (TSS), salinity, dissolved oxygen (DO), biochemical oxygen demand (BOD), and chemical oxygen demand. At each sampling station, the total number of plankton, fish, and macrobenthic taxa were counted and analyzed. The relationships between the physicochemical parameters and aquatic biodiversity were investigated with biotypological analysis, principal component analysis, hierarchical cluster analysis, and linear regression analysis. These analyses showed that the richness and diversity indices were generally influenced by salinity, temperature, TSS, BOD, and pH. The data obtained in this study supported the bioindicator concept. The findings, as they related to scientifically informed conservation, could serve as a model for Juru River management, as well as for river management throughout Malaysia and other tropical Asian countries. 展开更多
关键词 Anthropogenic disturbance Aquatic biodiversity River water quality urban river Hierarchical cluster analysis
下载PDF
Research Status of Water Quality Criteria and Standards and Analysis on the Transformation Methods
4
作者 Cheng LI Yihong WU +1 位作者 Yang ZHAO Ruyu YUAN 《Meteorological and Environmental Research》 CAS 2023年第3期69-72,共4页
Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue ... Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue of economic development and ecological protection in a coordinated way.However,all kinds of environmental benchmark values in China are lacking and need to be constantly supplemented and improved.Therefore,exploring and putting forward a simple and efficient method for the transformation of environmental criteria into environmental standards is an important basis for the rapid establishment of relevant environmental criteria system and the effective promotion of the development of environmental standards system towards a scientific and reasonable direction.In this paper,the water environment is taken as the research object.By analyzing the research progress of environmental criteria and standards at home and abroad,and the foreign method of transforming environmental criteria into environmental standards,combined with the problems faced in the process of transforming environmental criteria into environmental standards in China,an effective method to transform China's environmental criteria into environmental standards is analyzed.After analysis and comparison,it is found that the pollution reduction accounting method could achieve their simple and efficient conversion.Under the premise of obtaining environmental criteria for certain pollutants,environmental criteria for certain pollutants could be obtained by distributing pollutants reduction costs,and accounting economic benefits after reaching standard,thus obtaining the environmental standard of this type of pollutant,which provides reference to determine the environmental standard limits of such pollutants. 展开更多
关键词 water quality criteria water quality standards Research status Transformation mechanism
下载PDF
Households' Assessment of the Water Quality and Services of Multi-model Urban Water Supply System in the Informal Settlements of Dar es Salaam, Tanzania
5
作者 Francis Dakyaga Alphonce G. Kyessi Joel M. Msami 《Journal of Civil Engineering and Architecture》 2018年第5期362-381,共20页
In the global south wide range of studies highlight the limitations of the single-modelled public urban water system to meeting the endogenous water preferences of the urban population. Studies also touched on the com... In the global south wide range of studies highlight the limitations of the single-modelled public urban water system to meeting the endogenous water preferences of the urban population. Studies also touched on the complementary roles of private water actors to the single-modelled public water supply system in the urban water supply network. Multiple of urban water supply systems (multi-model) co-exist in the urban landscape of global south. However, it is unclear and largely inconclusive on the suitable and satisfactory urban water supply model that meets the water consumption needs of informal settlement dwellers in the global south. This study draws the experiences of households in the informal settlements using a case-study with cross-sectional survey strategy to assess the suitability of the multi-model urban water supply system for sustainable urban water supply in the informal settlements. A total of 292 households were randomly sampled alongside 35 purposively sampled private water actors and public water departments. The data were collected through face to face interviews. Findings show that water supply services of the multi-model water supply system are inevitably suitable for the water consumption needs of informal settlements’s dwellers. The operation of the multi-model water supply system is flexible and able to accommodate the diverse water consumption preferences and choices of the different socio-economic groups in the informal settlements. We observed that multiplicity of urban water supply system increases households’ access to water but does not necessarily improve the quality of water serve in the informal settlements. The paper recommended for the formalisation and adoption of the multi-model urban water supply system to meet the growing demand for improved water supply and services in the informal settlements. 展开更多
关键词 water quality multi-model water supply informal settlements urban water supply urban poor.
下载PDF
Performance of a Horizontal Flow Constructed Reed Bed Filter for Municipal Wastewater Treatment: The Case Study of the Prototype Installed at Gaston Berger University, Saint-Louis, Senegal
6
作者 Abdou Khafor Ndiaye Falilou Coundoul +2 位作者 Abdoulaye Deme Antonina Torrens Armengol Abdoulaye Senghor 《Natural Resources》 2024年第1期1-16,共16页
In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed... In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability. 展开更多
关键词 Constructed Wetlands Horizontal Flow Reed Beds Wastewater Treatment Phragmites and Typha Plants Physicochemical Pollutant Removal Microbiological Indicators Fecal Coliforms and Helminth Eggs water quality Improvement Senegal water Reuse standards Sustainable water Management Agricultural Irrigation Reuse Nutrient Removal Efficiency Environmental Engineering Ecological Sanitation Systems
下载PDF
Water quality of reclaimed water from treated urban wastewater in Chaobai River Basin,North China 被引量:2
7
作者 Yilei Yu Xianfang Song +2 位作者 Yinghua Zhang Fandong Zheng Licai Liu 《Chinese Journal of Population,Resources and Environment》 2014年第2期103-109,共7页
The utilization of reclaimed water could be an efficient tool to alleviate water scarcity,especially for dry river augmentation.However,it is crucial to monitor water quality to ensure safety to human health and to av... The utilization of reclaimed water could be an efficient tool to alleviate water scarcity,especially for dry river augmentation.However,it is crucial to monitor water quality to ensure safety to human health and to avoid negative effects on the environment.Reclaimed water samples were collected bimonthly from May to November in 2010 in Chaobai River,and the physiochemical parameters were determined.The main results are as follows:The parameters exceeding the threshold value of the water guidelines are mainly nutrition related to nitrogen and phosphorus,which are known to increase the risk of eutrophication in surface waters.Additionally,nitrite and nitrate can be detrimental to human health.The majority of the parameters have a peaking concentration in May,whereas others either show significant temporal variation over the entire period or remain relatively constant in all four months.Correlation analysis shows that some parameters(pH,T and B) have no significant correlation with others,whereas significant positive correlation was found for Sr with EC and TDS,for CI with TDS,for Si02 with TP and for NO3-N with TN and a significant negative correlation between SO4 and Ba.According to principal component analysis,60.108%of the total data is represented by dominant solutes,and the second principal component with a percentage of 31.876 comprises parameters related to nitrogen.Subsequent cluster analysis of parameters identified four groups,which represent different compositions,and samples in May differ from others. 展开更多
关键词 water quality treated urban wastewater water guidelines multivariate statistical analysis Chaobai River
下载PDF
Drinking Water Quality Surveillance in a Vulnerable Urban Ward of Ahmedabad
8
作者 Veena Iyer Nandini Choudhury +1 位作者 Gulrez Shah Azhar Bhushan Somvanshi 《Health》 2014年第11期1165-1171,共7页
The World Bank estimates that 21% of all communicable diseases in India are related to unsafe water with diarrhoea alone causing more than 0.1 million deaths annually. The WHO drinking water surveillance parameters of... The World Bank estimates that 21% of all communicable diseases in India are related to unsafe water with diarrhoea alone causing more than 0.1 million deaths annually. The WHO drinking water surveillance parameters of quality, quantity, accessibility, affordability and continuity were assessed in one vulnerable ward of Ahmedabad—a fast growing city in Western India. Interviews with key informants of the ward office, health centre and water supply department, secondary analysis and mapping of field test reports and a questionnaire-based survey of different household types were conducted. We found that Ahmedabad Municipal Corporation (AMC) supplies water to the ward intermittently for two hours during the day. Housing society clusters supplement their AMC water supply with untested bore-well water. The water quality surveillance system is designed for a twenty-four-hour piped distribution of treated surface water. However, in order to maintain surveillance over an intermittent supply that includes ground water, the sampling process should include periodic surveys of water actually consumed by the citizens. The laboratory capacity of the Central Water Testing Laboratory should expand to include more refined tests for microbial and chemical contamination. 展开更多
关键词 Ahmedabad GUJARAT DRINKING water quality water quality SURVEILLANCE urban India WHO DRINKING water quality
下载PDF
Urban Water Supply Industry Marketization of China in View of Public Water Service and Water Resource Management
9
作者 Wang Yining 1,2 1.Institute of Geographic Science and Natural Resources Research,CAS,Beijing 100101,China 2.Graduate School of the Chinese Academy of Sciences,Beijing 100049,China 《Chinese Journal of Population,Resources and Environment》 2010年第2期55-60,共6页
Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal... Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal of public water service equalization to some extent.The article also analyzes the problems emerged in urban water supply industry marketization reform and various rea-sons in view of efficiency and fairness.An efficiency and fairness oriented management model is built in this article to illustrate how the government should conciliate interests of various communities involved in the process of marketization reform of the urban water supply industry so as to actualize the coordination of efficiency and fairness.At the end,an assumption on urban water price is put forward to help achieve the public water service equalization. 展开更多
关键词 urban water supply industry MARKETIZATION public water service water resource management
下载PDF
Preliminary Study on Formulating Water Quality Standards for Estuaries of China
10
作者 Wang Liping Liu Lusan Zheng Binghui 《Meteorological and Environmental Research》 CAS 2014年第3期37-41,45,共6页
In China,the water quality standards in operation include the Environmental Quality Standard for Surface Water(GB3838-2002)and Water Quality Standards for Seawater(GB3097-1997).However,these two standards are curr... In China,the water quality standards in operation include the Environmental Quality Standard for Surface Water(GB3838-2002)and Water Quality Standards for Seawater(GB3097-1997).However,these two standards are currently not suitable for the estuarial zones of China because of the unique properties of water environment in estuaries.We proposed preliminarily a basic idea and technical workflow in formulating water quality standards for the estuaries of China based on analyzing the water environment properties of estuaries comprehensively and comparing various parameters and their standard values mentioned in these two standards above.Issues pertinent to the formulation of the water quality standards for estuaries,e.g.nutrient,heavy metals and persistent organic pollutants(POPs),are highly concerned.The objective of this paper is to provide technical support for the formulation of scientific water quality standards and the assessment of water quality of the estuaries of China. 展开更多
关键词 ESTUARY water quality standards NUTRIENT Heavy metal Persistent organic pollutants(POPs) China
下载PDF
Groundwater Quality Assessment for an Indian Urban Habitat: A GIS Approach
11
作者 A. Saleem M.N. Dandigi +1 位作者 K. Vijaykumar P. Balakrishnan 《Journal of Environmental Science and Engineering》 2011年第12期1561-1569,共9页
Groundwater is an essential source of drinking water for many Indian urban habitats. Large numbers of people consume ground water instead of municipal tap water due to contamination of tap water. Groundwater is extrac... Groundwater is an essential source of drinking water for many Indian urban habitats. Large numbers of people consume ground water instead of municipal tap water due to contamination of tap water. Groundwater is extracted from thousands of bore wells, and used for potable purpose without proper testing and treatment. This paper describes a groundwater quality monitoring strategy and database model developed for Gulbarga city, located in Karnataka, India. Sampling wells are selected one each in 55 wards of the city corporation having easy access for regular sampling. Various attributes of sampling wells including their spatial coordinates, location address and a photograph are registered for ready recognition on site. Water samples are collected and analyzed for various physico-chemical parameters. Spatial coordinates and levels of sampling points are measured on site using a hand held GPS instrument. Gulbarga city map is digitized. A GIS database of the measured spatial and water quality data is developed using ArcGIS Desktop 9.3, and ground water quality maps are prepared which may serve as useful tools for developing policy, and regulatory mechanism for sustainable groundwater use. 展开更多
关键词 GROUNDwater water quality GIS applications urban water supply drinking water.
下载PDF
Geostatistical Studies of Space-Temporal Variation in Selected Quality Parameters in Klodzko Water Supply System (SW Part of Poland)
12
作者 Barbara Namyslowska-Wilczyfiska 《Journal of Geological Resource and Engineering》 2015年第2期57-81,共25页
Selected results of research connected with the development of a (3D) geostatistical hydrogeocbemical model of the Klodzko city area, dedicated to the spatial and time variation in the quality parameters in the Klod... Selected results of research connected with the development of a (3D) geostatistical hydrogeocbemical model of the Klodzko city area, dedicated to the spatial and time variation in the quality parameters in the Klodzko water supply system (SW part of Poland) have been presented. The research covers the period 2007-2011. Spatial analyses of the variation in three quality parameters, i.e. Fe iron (g/m3) content, Mn manganese (g/m3) content and NI-I4+ ammonium ion (g/m3) content, were carried out. Spatial and time variation in the parameters was analyzed on the basis of the data (2007-2011). The input for the studies was the chemical determinations of the quality parameters of water samples taken in the Klodzko water supply system area (also treated water) in different periods of time. These data were subjected to spatial analyses using geostatistical methods. The parameters of the assumed theoretical models of directional semivariograms functions of the studied regionalized variables, were used in the ordinary (block) kriging estimation. Generally, the behaviour of the quality parameters in the Klodzko water supply system has been found to vary in space and time. Thanks to the multivariate spatial analyses some regularities in the variation in the water supply system in the Klodzko city area have been identified. In the considered time interval, the shapes of the directional Fe iron content semivariogram show a tendency to vary periodically. The courses of the directional semivariograms of Mn manganese content and NI-I4+ ammonium ion content show some tendencies towards directional variation over the passing years. There are visible distinct increasing trends of variability for Mn content and stronger variation are observed for NH4+ ion content. The kriging estimation results were used to determine the levels of elevated values 2* of the water quality parameters in the years 2007-2011 and to forecast these values for the years 2012-2014. The maximum values Z* of the quality parameters were stated for the years: 2007, 2008-2009 and 2012 (the decreasing trend in Fe iron content averages Z* variation towards the year 2012, the increasing trend in Mn content averages Z* variation towards the year 2012 and the increasing trend in NH4+ ion content averages Z* variation towards the years 2008-2009 and then the decreasing trend towards the year 2012). 展开更多
关键词 Treated water water supply system quality parameters spatio-temporal variation GEOSTATISTICS directional semivariogram ordinary kriging.
下载PDF
Development of emergency water quality standard for Cr^(6+) and Hg^(2+) in Liao River basin
13
作者 Yan Zhenguang Zheng Xin +4 位作者 Ye Jing Wang Xiaonan Wu Jiangyue Liu Zhengtao Meng Wei 《Engineering Sciences》 EI 2014年第2期45-51,共7页
The acute toxicity data of Cr+ and Hg2+ to the aquatic organisms in Liao River basin was collected and screened. Calculated results of criteria values using popular species sensitivity distribution (SSD) methods w... The acute toxicity data of Cr+ and Hg2+ to the aquatic organisms in Liao River basin was collected and screened. Calculated results of criteria values using popular species sensitivity distribution (SSD) methods were evaluated through data analysis. The comprehensive methodology of emergency water quality standards (EWQSs) was established on the basis of the SSD method of Australia and New Zealand according to the evalu- ation results. The affected fractions of the aquatic organisms were set to be 5 %, 15 %, 30 % and 50 %, corre- sponding to the risk grades of Ⅰ,Ⅱ,Ⅲ and IV, and four-grade EWQSs, respectively. The EWQSs for Cr6+ and Hg2. in the Liao River were derived and the corresponding risk indicators were also proposed. The results showed that the four-grade EWQSs for Cr6+ were 2.85 μg/L, 21.0 μg/L, 161 μg/L and 797 μ/L, respec- tively, and the risk indicators were daphnia (grade Ⅱ ), shrimp (grade Ⅲ), and the bighead fish or tadpole (grade IV). The four-grade EWQSs for Hg2+ were 0.59 μg/L, 2.32 μg/L, 6.25 μg/L and 15.6 μg/L, respective- ly, and the risk indicators were crucian carp or daphnia (grade Ⅱ), shrimp (grade Ⅲ), and worm or crab (grade IV). The results provided valuable information for the risk analysis of sudden ambient water environmen- tal pollution accident. 展开更多
关键词 Liao River Cr6+ Hg2+ emergency water quality standards risk indicators
下载PDF
Effects of Increasing Impervious Surface on Water Quality in Ile-Ife Urban Watershed, Southwestern Nigeria
14
作者 Olusola-Ige Olufayo Adetoro Victor Osarenren Samuel Oladimeji Popoola 《Journal of Geoscience and Environment Protection》 2022年第12期126-160,共35页
The urban environment has continued to experience changes from increasing impervious surfaces, which alters the proper functioning of the ecological zones and impairs water quality in the watershed. Impervious cover i... The urban environment has continued to experience changes from increasing impervious surfaces, which alters the proper functioning of the ecological zones and impairs water quality in the watershed. Impervious cover is predominantly used as an indicator to assist in understanding and forecasting the impact of human actions and other related activities on aquatic resources. In this study, the rate of change in land uses using the impervious surface as an indicator, and the percentage of imperviousness on the effect on water quality in the urban watershed were assessed. Ile-Ife was delineated as an urban watershed, and the percentage of imperviousness from 2008 to 2016 and the effect of imperviousness on water bodies were assessed. The study utilized ASTERDEM, Worldview (0.46 m), IKONOS (1.4 m), Landsat (30 m) for 2008 and 2016, GPS and Drone (10 cm). Water sampling was carried out in selected locations as generated by the impervious surface analyst tool, (ISAT). The percentage (%) of impervious surfaces accounted for 59.4% (4567.1/7691.5ha) in 2008 and 70.3% (5408.2/7691.5ha) in 2016, from the total number of lands investigated. The turbidity values from low to high regions were 32.3, 55.9 and 82.4 NUT. Changes in LULC of the watershed led to increased surface temperature, impermeable surfaces, and decreased vegetation, which exposes the area to flooding and reduced water quality. This study emphasized the importance of GIS and its integration into urban changes and water quality assessment. 展开更多
关键词 urban watershed Impervious Surface water quality ISAT OBIA TURBIDITY
下载PDF
Water quality characterization of road runoff in urban area of Guangzhou, China
15
作者 Huayang GAN Muning ZHUO +1 位作者 Dingqiang LI Yongzhang ZHOU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期144-144,共1页
关键词 广州市 城市道路 水质 降水量 水体污染
下载PDF
Complex Sequence Quality Evaluation Model for Concealed Water Supply Pipeline of Prefabricated Construction
16
作者 HAN Shasha CHEN Qun +1 位作者 LI Jie DAI Yijing 《Journal of Donghua University(English Edition)》 EI CAS 2019年第2期179-186,共8页
The accurate assessment of the quality can materially affect the safety and life of the prefabricated construction.In this paper,we studied the overall module of concealed water supply pipeline,and a new complex seque... The accurate assessment of the quality can materially affect the safety and life of the prefabricated construction.In this paper,we studied the overall module of concealed water supply pipeline,and a new complex sequence quality evaluation model was established.By analyzing the small evaluation index elements of the model,the weight of the larger evaluation index could be deduced.The total quality evaluation score of the overall module could be obtained by calculating the weight value of the evaluation index,and then the quality standard of the overall module could be obtained. 展开更多
关键词 PREFABRICATED construction concealed water supplypipeline overall MODULE COMPLEX SEQUENCE quality EVALUATION model quality EVALUATION system
下载PDF
Discussion about the standard system on urban domestic water saving technology in China
17
作者 YANG Shujun, REN Xiaoli ,GAO Benhu 《China Standardization》 2007年第2期2-5,共4页
Standard is the technical foundation of national economic and social development, and it is the basic rule of establishing social regulation. Researching and constituting the standard system of urban domestic water sa... Standard is the technical foundation of national economic and social development, and it is the basic rule of establishing social regulation. Researching and constituting the standard system of urban domestic water saving technology is to offer important science basis for revising standard plan and standardize research plan. This paper introduces the present situation of our urban domestic water saving technical standard system, problem and the development direction in the future, as well as project planning of constructing urban domestic water saving technical standard system. 展开更多
关键词 standard system urban domestic water saving technology water shortage Project plan
下载PDF
Assessing Localized Contamination Hazard and Groundwater Quality Challenges in Water-Stressed Peri-Urban Accra, Ghana
18
作者 Stephen Twumasi Annan Bright Frimpong +1 位作者 Collins Owusu-Fordjour Bismark Yeboah Boasu 《Journal of Geoscience and Environment Protection》 2022年第1期13-28,共16页
The study assesses the quality of hand dug wells in relation to distance from soakaway septic tanks in three selected peri-urban communities in the Ga West Municipality near Accra, Ghana. Water quality analyses of bio... The study assesses the quality of hand dug wells in relation to distance from soakaway septic tanks in three selected peri-urban communities in the Ga West Municipality near Accra, Ghana. Water quality analyses of bio-physico-chemical variables (pH, Temperature, EC, turbidity, DO, BOD, TSS, TDS, sodium, potassium, nitrate, nitrite, ammonia, sulphate, chloride, salinity, total alkalinity, total coliform, fecal coliforms and isolation of <i>E. coli</i>) were determined. Concentrations of the major nutrient anion sulphate, nitrate, phosphate, and chlorides in water samples at distances between 0</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">30 m radial distances from the septic tank were above the WHO permissible limit of drinking water compared to the control. All the water samples had high fecal and total coliform counts that exceeded the international standard of 0 per 100 mL of potable water with counts ranging from 0</span><span style="font-family:""> - </span><span style="font-family:"">143</span><span style="font-family:""> </span><span style="font-family:"">cfu/100</span><span style="font-family:""> </span><span style="font-family:"">ml and 53</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">463/100</span><span style="font-family:""> </span><span style="font-family:"">ml for FC and TC respectively. High fecal coliform and detection of <i>E. coli</i> in most samples is an indication of fecal pollution possibly from their close proximity to soak away septic sewage. The high nutrient levels detected in samples at distances between 0</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">30</span><span style="font-family:""> </span><span style="font-family:"">m as compared to the controls may also be attributed to its close proximity to septic tanks. This study, therefore, accentuates the need for the owners of the water points to site their water source at least 30m away </span><span style="font-family:"">from </span><span style="font-family:"">localized sources of pollution as well as treatment of groundwater before use. 展开更多
关键词 GROUNDwater water quality Localized Contamination PERI-urban
下载PDF
The Effect of Land Use Change on Soil and Water Quality in Northern Iran 被引量:7
19
作者 KHALEDIAN Yones KIANI Farshad EBRAHIMI Sohaila 《Journal of Mountain Science》 SCIE CSCD 2012年第6期798-816,共19页
Rapid urbanization has led to extensive land-use changes,particularly in developing countries.This research is aimed to investigate the role of land use and its effect on soil and water quality in Ziarat watershed foc... Rapid urbanization has led to extensive land-use changes,particularly in developing countries.This research is aimed to investigate the role of land use and its effect on soil and water quality in Ziarat watershed focusing on four land uses:forest,pasture,cultivated and urban development.Soil samples were taken from a depth of 0-30 cm on each land use and were analyzed by completely randomized split-plot design in two geographical directions.Results showed that bulk density(BD),electrical conductivity(EC),pH,calcium carbonate equivalent(CCE),and soil particle density(DS) of the soil samples in pastures,cultivated and urban areas increased and the mean weight diameter(MWD),soil porosity(F),organic carbons(OC),total nitrogen(TN),exchangeable cations(Ca 2+,Mg 2+,K +,Na +),cation exchange capacity(CEC) and soil microbial respirations(SMR) decreased,respectively in comparison with the forest soils.For water quality evaluations,sodium adsorption ratio(SAR),electrical conductivity(EC),pH,total dissolved solids(TDS),bicarbonate(HCO 3),chloride(Cl),total hardness(TH),calcium(Ca 2+),potassium(K +),sodium(Na +) and magnesium(Mg 2+) were investigated in two areas:Nahrkhoran and Abgir stations.Results showed that the concentration of TDS,EC and HCO 3 in Naharkhoran station is higher than that in Abgir station.On the other hand,the concentration of TDS,EC and HCO 3 in Abgir station are the relatively higher due to its location.Total hardness had the same trend during the study years except in the last three years;however,TH showed an increase of 25% TH in Naharkhoran for the last two years.Cl,K + and SAR in Naharkhoran station increased by 61%,22%,78% and 56% respectively,in comparison with Abgir station.This study demonstrated that the trend of soil degradation and mismanagement of land use may increase the frequency of urban floods and human health problems. 展开更多
关键词 DEFORESTATION Organic matter loss Soil degradation Soil quality urbanIZATION water quality
下载PDF
Effect of continuous negative pressure water supply on the growth, development and physiological mechanism of Capsicum annuum L. 被引量:8
20
作者 LI Di LONG Huai-yu +3 位作者 ZHANG Shu-xiang WU Xue-ping SHAO Hong-ying WANG Peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期1978-1989,共12页
Effects of continuous negative pressure water supply on water consumption, growth and development, as well as physiological mechanism and quality of Capsicum annuum L. were investigated in this paper. Meanwhile, the o... Effects of continuous negative pressure water supply on water consumption, growth and development, as well as physiological mechanism and quality of Capsicum annuum L. were investigated in this paper. Meanwhile, the optimal negative pressure water supply conditions for growth of C. annuum L. were screened out to achieve the goals of water conservation, high yield and high quality, thus providing theoretical foundation for its field production. The pot experiment within the greenhouse was utilized; the continuous negative pressure water supply was adopted; the four treatments, artificial watering(CK), –5 k Pa(T1), –10 k Pa(T2), and –15 k Pa(T3) were set; and the daily water consumption, yield, as well as the biomass, nitrate reductase, root activity, vitamin C, capsaicin, and nutrient uptakes of nitrogen(N), phosphorus(P) and potassium(K) during various stages of its growth were determined. Compared with CK, when the water supply pressure was controlled at –5 to –15 k Pa in the experiment, the total water consumption of C. annuum L. reduced by 53.42 to 67.75%, the total water consumption intensity reduced by 54.29 to 67.14%, and the water use efficiency increased by 12.66 to 124.67%. The N accumulation in a single strain of C. annuum L. from the color turning stage to the red ripe stage increased by 15.99 to 100.55%, respectively, compared with that of CK; the P accumulation increased by 20.47 to 154.00% relative to that of CK, and the K accumulation increased by 64.92 to 144.9% compared with that of CK. Compared with CK, C. annuum L. yield was remarkably improved by 13.79% at T1, and contents of vitamin C, capsaicin as well as carotenoids at all growth stages were enhanced by 13.42–147.01%, 11.54–71.01%, and 41.1–568.06%, respectively. Nitrate reductase activity, root activity and chlorophyll(a+b) were markedly increased by 335.78–500%, 79.6–140.68% and 114.95–676.19%, respectively, from immature stage to full ripe stage. Adopting the continuous negative pressure water supply for C. annuum L. has a significant water-saving effect, and the water supply pressure being stable at –5 k Pa contributes to its growth and development, improves yield, enhances root activity, promotes nutrient uptake, and improves its quality, thus achieving the effects of water conservation, high yield, high quality and high efficiency. 展开更多
关键词 negative pressure water supply Capsicum annuum L. physiological indexes yield quality
下载PDF
上一页 1 2 168 下一页 到第
使用帮助 返回顶部