An ecological project called fish biomanipulation, other than the conventional fishery culture technique, was put forward in this paper for the excess propagation control of Cyclops. The control effects on Cyclops of ...An ecological project called fish biomanipulation, other than the conventional fishery culture technique, was put forward in this paper for the excess propagation control of Cyclops. The control effects on Cyclops of four species of fish were investigated experimentally at stocking density of 30 g per cubic meter of water. The experimental results showed that the food habit of the fish had significant influence on the biological control of Cyclops. The propagation of Cyclops could be controlled effectively and also the water quality was improved simultaneously by stocking the filter-feeding fishes, such as silver carp and bighead carp. Whereas, herbivorous Ctenopharyugodon idellus and omnivorous Cyprinus carpio had no obvious biological effects on controlling the growth of Cyclops and restoring water quality. The results further proved that under condition of proper poly-culture density of silver carp and bighead carp, the number of Cyclops might be controlled at very low level and the eutrophication might be abated by removing the nutrients from water body.展开更多
The access to safe drinking-water is a global priority for sustainable development, as it has been recognized within the MDGs (Millennium Development Goals). Although the MDG’s target of halving the proportion of p...The access to safe drinking-water is a global priority for sustainable development, as it has been recognized within the MDGs (Millennium Development Goals). Although the MDG’s target of halving the proportion of people without sustainable access to safe drinking-water was met in 2010, the measurement method of the monitoring and evaluation indicator used ignored certain elements including the quality of water that should be underlined. Starting with a review of drinking-water and improved water source concepts, this study examines the limitations of measuring access to safe drinking-water in the context of the MDGs, and learns from the lessons to ensure a better performance in achieving the SDGs (Sustainable Development Goals).展开更多
This paper briefly introduced the evolution of purification technology for drinking water over time. After description of the 1st generation processes in the beginning of the 20th century - conventional processes and ...This paper briefly introduced the evolution of purification technology for drinking water over time. After description of the 1st generation processes in the beginning of the 20th century - conventional processes and the 2nd generation processes in 1970s - advanced treatment processes, a tertiary processes - UF (ultrafiltration) based on integrated processes was proposed. Moreover, reaction measures (dosing variety of regents for different contaminants) for urban source water emergencies were illustrated in brief. A new technology of KMnO4 and potassium permanganate composite (PPC) for drinking water purification which was developed by Harbin Institute of Technology (HIT) was concisely introduced.展开更多
Underground water (Borehole) has been the main alternative source of drinking water for most communities in my country. Previous studies have revealed high levels of contamination. The origin of which can be attribu...Underground water (Borehole) has been the main alternative source of drinking water for most communities in my country. Previous studies have revealed high levels of contamination. The origin of which can be attributed to geochemical processes, combustion of fossil fuels, mining and anthropogenic activities. Most borehole water and well water in local communities of Nigeria are not safe for drinking due to heavy industrial and environmental pollution. This study was undertaken to assess the quality in some selected boreholes in the Port Harcourt metropolis for a period of two years. Borehole water samples were randomly collected from thirteen boreholes in a local community in plastic bottles (100 mL) in the months of September for the years of study (2010 & 2011). Four out of the seven heavy metals analyzed were found to be present in the first year of study. These were Fe, Cu, Mn and Zn. In the second year of study, Pb, Cr, Fe and Co were not detected in all of the samples except Cu and Fe which were present in only two samples. Mn and Zn were found to be present in all of the samples for both years of study.展开更多
Water comes from various different sources, such as lakes, rivers, streams, springs and boreholes. Depending on the quality of its source, water will almost certainly have to be treated to make it safe to drink. All w...Water comes from various different sources, such as lakes, rivers, streams, springs and boreholes. Depending on the quality of its source, water will almost certainly have to be treated to make it safe to drink. All water supplies for human consumption must be well stored, free from micro-organisms, parasites and any substances that endanger public health if found in sufficient numbers or concentrations, in the same time. In our continued effort for a better result in our study of qualitative aspects, by physicochemical and bacteriological analysis, the authors focus in two crucial questions: a) is the water quality of Sidi-bel-Abbes good or bad ,and well stored? b) is the people of Sidi-bel-Abbes are aware of the importance of water and knowledgeable about how to use this vital? This study is the first to use data from I real work based upon a developed method and a good investigation to know exactly if water of Sidi-Bel-Abbes is safely treated, well stored and consumed in resemble way. In first, the authors plotted the method in analysing the qualitative aspect of water using developed material for a precise result starting by the distribution connection (condition and management) and the verification of water tank storage and finishing by analyzing the all the aspect of water (physicochemical and bacteriological analysis). In second, the authors focus on the way that people of Sidi Bel Abbes used and consumption water by introducing a targeted method (questionnaires) which help us a lot to know precisely the way, time and the real quantity of water consumed daily. In final step of our study of qualitative aspects, by physico-chemical and bacteriological, and environmental analyses, investigation processed by PCA (principal component analysis) of the drinking water supplied to Sidi Bel Abbes city (Algeria north-west) concluded by an encouraging result, that despite the various constraints faced by the departments concerned, they ensure the supply of safe drinking water in households almost daily.展开更多
Coastal areas of Bangladesh are especially vulnerable due to their physiographic location and exposure to natural calamities. Around 35 million people living in coastal areas have no access or limited access to safe d...Coastal areas of Bangladesh are especially vulnerable due to their physiographic location and exposure to natural calamities. Around 35 million people living in coastal areas have no access or limited access to safe drinking water. Contamination of water sources by salinity, arsenic or iron are the principal causes of water scarcity. Rising sea levels and unevenness of climatic events due to climate change will exacerbate the situation in coastal areas, especially in the southwestern coastal zone. This study examines one of the vulnerable coastal upazila Tala at Satkhira(an 'upazila' is a medium level administrative unit in Bangladesh) in the southwestern zone of Bangladesh to understand the gravity of the problems. The study develops a GIS based multi-criteria analysis to identify suitable options and locations of fresh water as part of a current and future solution to the problems and further deterioration. To fulfill the objectives, a questionnaire-based GPS guided field survey was conducted to collect details of field level conditions in order to find a suitable solution. Because aquifers are considered the primary source of drinking water, field data have been analyzed for two distinct aquifers, one relatively shallow and one deeper, to understand aquifer quality. Potentiality of different water sources the socioeconomic status of communities, types of water use and corresponding sources and water demand are also evaluated. The analysis finds that alternative water sources that are safe are difficult to find, because both surface and groundwater-based sources are already contaminated, and there are no nearby, easily accessible safe sources. Groundwater-based sources are contaminated by arsenic, iron or salinity, and surface water-based sources are not in use due to maintenance and management issues. In some cases, surface water sources are polluted by flash flooding of high saline water during storm surges or seepage from saline water-based aquacultures. Multiple limitations identified during field observations and field data analysis were considered as an analytical parameter A GIS based multi-criteria analysis incorporated field data, including Geo-spatial and socioeconomic information for road networks, settlement locations, number of households, quality and quantity of existing water sources, water demand and business opportunities. The analysis found some potential options in distributed locations which are consistent with community demand. Suggested options made use of technologies that are already understood and commonly used by communities, like deep tubewells, PSFs(Pond Sand Filter) and WTPs(Water Treatment Plant). In the study area, PSF is the most commonly used method and to make this surface water-based technology sustainable some precautionary measurements are suggested.展开更多
基金Sponsored by the Hi-Tech Research and Development Program of China (Grant No. 2002AA601140 )the National Science Foundation of Heilongjiang Province (Grant No. QC03C17)the Focal Laboratory Opening Research Program of Beijing and the Scientific Resear
文摘An ecological project called fish biomanipulation, other than the conventional fishery culture technique, was put forward in this paper for the excess propagation control of Cyclops. The control effects on Cyclops of four species of fish were investigated experimentally at stocking density of 30 g per cubic meter of water. The experimental results showed that the food habit of the fish had significant influence on the biological control of Cyclops. The propagation of Cyclops could be controlled effectively and also the water quality was improved simultaneously by stocking the filter-feeding fishes, such as silver carp and bighead carp. Whereas, herbivorous Ctenopharyugodon idellus and omnivorous Cyprinus carpio had no obvious biological effects on controlling the growth of Cyclops and restoring water quality. The results further proved that under condition of proper poly-culture density of silver carp and bighead carp, the number of Cyclops might be controlled at very low level and the eutrophication might be abated by removing the nutrients from water body.
文摘The access to safe drinking-water is a global priority for sustainable development, as it has been recognized within the MDGs (Millennium Development Goals). Although the MDG’s target of halving the proportion of people without sustainable access to safe drinking-water was met in 2010, the measurement method of the monitoring and evaluation indicator used ignored certain elements including the quality of water that should be underlined. Starting with a review of drinking-water and improved water source concepts, this study examines the limitations of measuring access to safe drinking-water in the context of the MDGs, and learns from the lessons to ensure a better performance in achieving the SDGs (Sustainable Development Goals).
文摘This paper briefly introduced the evolution of purification technology for drinking water over time. After description of the 1st generation processes in the beginning of the 20th century - conventional processes and the 2nd generation processes in 1970s - advanced treatment processes, a tertiary processes - UF (ultrafiltration) based on integrated processes was proposed. Moreover, reaction measures (dosing variety of regents for different contaminants) for urban source water emergencies were illustrated in brief. A new technology of KMnO4 and potassium permanganate composite (PPC) for drinking water purification which was developed by Harbin Institute of Technology (HIT) was concisely introduced.
文摘Underground water (Borehole) has been the main alternative source of drinking water for most communities in my country. Previous studies have revealed high levels of contamination. The origin of which can be attributed to geochemical processes, combustion of fossil fuels, mining and anthropogenic activities. Most borehole water and well water in local communities of Nigeria are not safe for drinking due to heavy industrial and environmental pollution. This study was undertaken to assess the quality in some selected boreholes in the Port Harcourt metropolis for a period of two years. Borehole water samples were randomly collected from thirteen boreholes in a local community in plastic bottles (100 mL) in the months of September for the years of study (2010 & 2011). Four out of the seven heavy metals analyzed were found to be present in the first year of study. These were Fe, Cu, Mn and Zn. In the second year of study, Pb, Cr, Fe and Co were not detected in all of the samples except Cu and Fe which were present in only two samples. Mn and Zn were found to be present in all of the samples for both years of study.
文摘Water comes from various different sources, such as lakes, rivers, streams, springs and boreholes. Depending on the quality of its source, water will almost certainly have to be treated to make it safe to drink. All water supplies for human consumption must be well stored, free from micro-organisms, parasites and any substances that endanger public health if found in sufficient numbers or concentrations, in the same time. In our continued effort for a better result in our study of qualitative aspects, by physicochemical and bacteriological analysis, the authors focus in two crucial questions: a) is the water quality of Sidi-bel-Abbes good or bad ,and well stored? b) is the people of Sidi-bel-Abbes are aware of the importance of water and knowledgeable about how to use this vital? This study is the first to use data from I real work based upon a developed method and a good investigation to know exactly if water of Sidi-Bel-Abbes is safely treated, well stored and consumed in resemble way. In first, the authors plotted the method in analysing the qualitative aspect of water using developed material for a precise result starting by the distribution connection (condition and management) and the verification of water tank storage and finishing by analyzing the all the aspect of water (physicochemical and bacteriological analysis). In second, the authors focus on the way that people of Sidi Bel Abbes used and consumption water by introducing a targeted method (questionnaires) which help us a lot to know precisely the way, time and the real quantity of water consumed daily. In final step of our study of qualitative aspects, by physico-chemical and bacteriological, and environmental analyses, investigation processed by PCA (principal component analysis) of the drinking water supplied to Sidi Bel Abbes city (Algeria north-west) concluded by an encouraging result, that despite the various constraints faced by the departments concerned, they ensure the supply of safe drinking water in households almost daily.
基金The Colleges and Universities Humanities and Social Science Fund Project in Jiangxi Province(JC1414).
文摘Coastal areas of Bangladesh are especially vulnerable due to their physiographic location and exposure to natural calamities. Around 35 million people living in coastal areas have no access or limited access to safe drinking water. Contamination of water sources by salinity, arsenic or iron are the principal causes of water scarcity. Rising sea levels and unevenness of climatic events due to climate change will exacerbate the situation in coastal areas, especially in the southwestern coastal zone. This study examines one of the vulnerable coastal upazila Tala at Satkhira(an 'upazila' is a medium level administrative unit in Bangladesh) in the southwestern zone of Bangladesh to understand the gravity of the problems. The study develops a GIS based multi-criteria analysis to identify suitable options and locations of fresh water as part of a current and future solution to the problems and further deterioration. To fulfill the objectives, a questionnaire-based GPS guided field survey was conducted to collect details of field level conditions in order to find a suitable solution. Because aquifers are considered the primary source of drinking water, field data have been analyzed for two distinct aquifers, one relatively shallow and one deeper, to understand aquifer quality. Potentiality of different water sources the socioeconomic status of communities, types of water use and corresponding sources and water demand are also evaluated. The analysis finds that alternative water sources that are safe are difficult to find, because both surface and groundwater-based sources are already contaminated, and there are no nearby, easily accessible safe sources. Groundwater-based sources are contaminated by arsenic, iron or salinity, and surface water-based sources are not in use due to maintenance and management issues. In some cases, surface water sources are polluted by flash flooding of high saline water during storm surges or seepage from saline water-based aquacultures. Multiple limitations identified during field observations and field data analysis were considered as an analytical parameter A GIS based multi-criteria analysis incorporated field data, including Geo-spatial and socioeconomic information for road networks, settlement locations, number of households, quality and quantity of existing water sources, water demand and business opportunities. The analysis found some potential options in distributed locations which are consistent with community demand. Suggested options made use of technologies that are already understood and commonly used by communities, like deep tubewells, PSFs(Pond Sand Filter) and WTPs(Water Treatment Plant). In the study area, PSF is the most commonly used method and to make this surface water-based technology sustainable some precautionary measurements are suggested.