The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the coll...The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal.展开更多
Crop carbon and water relations research is important in the studies of water saving agriculture, breeding program, and energy and material cycles in soil plant atmosphere continuum （SPAC）. The purpose of this paper...Crop carbon and water relations research is important in the studies of water saving agriculture, breeding program, and energy and material cycles in soil plant atmosphere continuum （SPAC）. The purpose of this paper is to review the current state of knowledge on stable isotopes of carbon, oxygen, and hydrogen in the research of crop carbon and water relations, such as carbon isotope discrimination （△^13C） during carbon fixation process by photosynthesis, application of △^13C in crop water use efficiency （WUE） and breeding programs, oxygen isotope enrichment during leaf water transpiration, CO2 fixation by photosynthesis and release by respiration, application of hydrogen isotope composition （619） and oxygen isotope composition （6180） for determination of water source used by a crop, stable isotope coupling Keeling plot for investigating the carbon and water flux in ecosystem, energy and material cycle in SPAC and correlative integrative models on stable isotope. These aspects contain most of the stable isotope researches on crop carbon and water relations which have been widely explored internationally while less referred in China. Based on the reviewed literatures, some needs for future research are suggested.展开更多
Water pollution is a steadily worsening problem because of growth in the chemical, pharmaceutical, leather, textile, and mining industries. In addition, municipal wastewater further contributes to polluting pure water...Water pollution is a steadily worsening problem because of growth in the chemical, pharmaceutical, leather, textile, and mining industries. In addition, municipal wastewater further contributes to polluting pure water sources. Hence, adequate treatment is essential before it released to avoid pollution of pure water sources. Chapter 3 describes guidelines for wastewater treatment taking into account its physical, chemical and mechanical nature. The guidelines are also helpful in maintaining the operational treatment facilities;it is estimated that 10 to 20 percent of wastewater treatment facilities even in developed countries are not operating properly. Treatment methods are divided into conventional and Natural biological processes and the advantages and drawbacks of each are clearly explained. The influential parameters are identified for the primary (settling to remove solid wastes), secondary (bacteria in removing pollutants) and tertiary (involving advanced techniques such as Biological Nutrient Removal) water purification methods, particularly municipal wastewater treatments. The biological treatment process via microorganisms is particularly suited for Lagoons, Ponds and wetlands because they avoid secondary by-products contaminants. Guidelines are given for the construction of artificial lakes and ponds to be used for wastewater treatment, and diagrams, designs, schemes, and mathematical models are provided. These can also be used for some difficult industrial wastewaters as well as for municipal water containing pharmaceuticals and personal care products. The author emphasized that wetland treatment is often the best choice for the pre-treatment of water and wastewater based on cost and the efficiency. This wastewater treatment chapter is very useful for environment researchers, and engineers, ecologist and the environmental education programs.展开更多
以2000-2021年Web of Science 3大引文数据库和中国知网收录的524篇流域初始水权分配研究文献为基础,利用Citespace软件对文献的作者研究机构与团队、关键词进行了可视化分析,并综述了流域初始水权分配方法的研究进展。结果表明:流域初...以2000-2021年Web of Science 3大引文数据库和中国知网收录的524篇流域初始水权分配研究文献为基础,利用Citespace软件对文献的作者研究机构与团队、关键词进行了可视化分析,并综述了流域初始水权分配方法的研究进展。结果表明:流域初始水权分配实质上是将流域多年平均水资源量(或某一水文频率下的天然径流量)作为流域用水总量控制指标,按照“流域区域行业”水权科层制分配模式,分配给流域内所辖各行政区及行业,以推进区域均衡协调发展与产业结构优化升级;在流域初始水权分配过程中,主要依据流域所辖各行政区的经济社会特征,统筹体现社会公平、经济效益、生态保护、风险控制等多维目标,明确水权分配原则,设计水权分配指标体系,建立基于分配模式的初始水权分配模型。指出今后亟须深入贯彻落实“以水定产”绿色发展理念,强化水资源刚性约束与双控行动,探索流域初始水权与产业结构优化适配模式。展开更多
文摘The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal.
基金supported by the National Basic Re-search Program of China (973 Program) (2005CB121103)the Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-YW-406KSCX1-YW-09-05)
文摘Crop carbon and water relations research is important in the studies of water saving agriculture, breeding program, and energy and material cycles in soil plant atmosphere continuum （SPAC）. The purpose of this paper is to review the current state of knowledge on stable isotopes of carbon, oxygen, and hydrogen in the research of crop carbon and water relations, such as carbon isotope discrimination （△^13C） during carbon fixation process by photosynthesis, application of △^13C in crop water use efficiency （WUE） and breeding programs, oxygen isotope enrichment during leaf water transpiration, CO2 fixation by photosynthesis and release by respiration, application of hydrogen isotope composition （619） and oxygen isotope composition （6180） for determination of water source used by a crop, stable isotope coupling Keeling plot for investigating the carbon and water flux in ecosystem, energy and material cycle in SPAC and correlative integrative models on stable isotope. These aspects contain most of the stable isotope researches on crop carbon and water relations which have been widely explored internationally while less referred in China. Based on the reviewed literatures, some needs for future research are suggested.
文摘Water pollution is a steadily worsening problem because of growth in the chemical, pharmaceutical, leather, textile, and mining industries. In addition, municipal wastewater further contributes to polluting pure water sources. Hence, adequate treatment is essential before it released to avoid pollution of pure water sources. Chapter 3 describes guidelines for wastewater treatment taking into account its physical, chemical and mechanical nature. The guidelines are also helpful in maintaining the operational treatment facilities;it is estimated that 10 to 20 percent of wastewater treatment facilities even in developed countries are not operating properly. Treatment methods are divided into conventional and Natural biological processes and the advantages and drawbacks of each are clearly explained. The influential parameters are identified for the primary (settling to remove solid wastes), secondary (bacteria in removing pollutants) and tertiary (involving advanced techniques such as Biological Nutrient Removal) water purification methods, particularly municipal wastewater treatments. The biological treatment process via microorganisms is particularly suited for Lagoons, Ponds and wetlands because they avoid secondary by-products contaminants. Guidelines are given for the construction of artificial lakes and ponds to be used for wastewater treatment, and diagrams, designs, schemes, and mathematical models are provided. These can also be used for some difficult industrial wastewaters as well as for municipal water containing pharmaceuticals and personal care products. The author emphasized that wetland treatment is often the best choice for the pre-treatment of water and wastewater based on cost and the efficiency. This wastewater treatment chapter is very useful for environment researchers, and engineers, ecologist and the environmental education programs.
文摘以2000-2021年Web of Science 3大引文数据库和中国知网收录的524篇流域初始水权分配研究文献为基础,利用Citespace软件对文献的作者研究机构与团队、关键词进行了可视化分析,并综述了流域初始水权分配方法的研究进展。结果表明:流域初始水权分配实质上是将流域多年平均水资源量(或某一水文频率下的天然径流量)作为流域用水总量控制指标,按照“流域区域行业”水权科层制分配模式,分配给流域内所辖各行政区及行业,以推进区域均衡协调发展与产业结构优化升级;在流域初始水权分配过程中,主要依据流域所辖各行政区的经济社会特征,统筹体现社会公平、经济效益、生态保护、风险控制等多维目标,明确水权分配原则,设计水权分配指标体系,建立基于分配模式的初始水权分配模型。指出今后亟须深入贯彻落实“以水定产”绿色发展理念,强化水资源刚性约束与双控行动,探索流域初始水权与产业结构优化适配模式。
