西安市城镇居民阶梯水价优化及节水效果研究

阶梯水价对于抑制城镇居民不合理用水具有重要现实意义。为了更好地发挥其杠杆作用,分析了西安市现行阶梯水价情况,采用供求关系定价模型,测算了2000—2020年水价、人均用水量及人均可支配收入的相关性和弹性系数,从用水量标准、居民接受度、加大阶梯水价级差、水费支出系数角度设计了4种阶梯水价优化方案,分析其节水效果,预测了未来几年水费支出系数。结果表明：西安市水费支出系数较小,阶梯水价应适当提高;水价、人均用水量与人均可支配收入存在显著的相关性,水价和人均可支配收入的弹性系数分别为-0.476、0.329;4种阶梯水价优化方案的一阶水价提升范围为0.71~1.30元/m³,均能在不同程度发挥节水作用,其中方案4阶梯水价提升幅度最高,节水效果最佳,方案1和方案3从城市居民生活用水标准出发,适度提高水价,节水效果居中,方案2阶梯水价及水量调整幅度较小,节水效果较差;长期保持同一水价,水费支出系数会逐渐减少。研究成果可为城镇居民阶梯水价改革提供参考。     

基于多智能体的城镇家庭用水量模拟预测分析

提出了基于多智能体的城镇家庭用水量模拟模型(MA-UHWDS),通过构造不同发展情景,对家庭用水量变化趋势及其影响因素进行了分析。以青岛市为实证城市,采用2003—2012年统计资料,计算分析了居民用水边际消费倾向、基本用水需求和不同收入户人均用水量,并对不同情景下2013—2022年各类收入户人均用水量和城镇家庭用水总量进行了定量模拟预测分析。结果表明:2003—2012年中,城镇家庭平均水费支出占总消费支出的比重仅为0.395%,易造成居民节水意识淡薄,最低收入户人均用水量除2008年外均低于基本需水量,而最高收入户平均超过基本需水量14.16 m3,水价改革需综合考虑低收入家庭的支付能力和高收入家庭的过度用水;2022年7类收入户在水价高增长收入低增长情景下的人均用水量与在水价低增长收入高增长情景相比下,分别减少了16.7%、18.4%、18.1%、16.1%、15.0%、17.8%和13.8%,水价和收入会明显影响家庭用水量。MA-UHWDS为区域用水总量调控提供了新的研究思路和工具。     

城镇居民生活用水的需水函数分析和水价节水效果评估

结合北京市统计数据分析表明，城镇居民人均年生活用水量与居民生活用水购买力系数（居民可支配收入与生活用水水价的比值）关系十分显著，本文在此基础上．探讨并建立了城镇居民生活用水的需求函数和水价节水效果的评估方法。实例测算结果表明，北京市城镇居民生活用水购买力系数的边际弹性为0．38．亦即北京市城镇居民生活用水购买力降低1％，城镇居民生活用水量减少0．38％；提高水价具有显著的节水效果，“十五”期间北京市城镇居民用水的水价累计节水量达到了0．9亿m^3，人均年节水量2m^3；现状北京市不同收入人群城镇居民水费支出占可支配收入的比例均小于1．0％，低于国际通行的评判可承受标准值2．5％，表明北京市城镇居民对水价承受能力比较大，水价仍有较大上升空间。     

实施两部制水价的利与弊

实行两部制水价,即一部分是按额定分配水量计算的固定收费,无论用水户是否用水,这部分水费必须支付;另一部分是按实际用水量计算的可变收整,水费多少完全取决于实际用水量.对省直供水单位实施两部制水价进行了利弊分析.     

基于ELES模型的城镇居民生活用水水价支付能力研究——以北京市为例

本文从支付能力的角度,根据计量经济学的需求函数理论,以我国城镇居民消费支出结构数据为基础,提出了应用扩展线性支出系统(ELES)模型,分析城镇居民生活用水水价支付能力。以北京市为例,采用1998～2004年截面数据资料,计算分析了不同时期居民用水需求与水费支出水平、居民用水的边际消费倾向、需求收入弹性以及不同收入户的用水基本需求等,以此定量研究了北京市城镇居民生活用水水价的支付能力。研究结果表明:平均收入水平下,居民对水价具有一定的支付能力,其基本用水需求均能得到满足;可支配收入增长对居民用水需求的影响不大;北京市生活用水水价还有上调的空间,但低收入户的水价支付能力有限,是重点考虑的对象。     

张峰水库供水价格及未来发展策略分析

为促进张峰水库供水市场开发,采用水费支出能力指数分析法,对居民生活用水、工业用水的水费支出能力进行分析,测算张峰水库未来供水水价。计算结果表明:2018年后,全线平均终端水价为3.5~4.2元/m3,其中工业用水、生活用水、农业用水终端水价分别为3.6~4.4、4.1~4.5、1.7~2.4元/m3。在市场开发初期,应充分考虑现行水价,以开拓市场为主,逐步提高受水地区用户终端供水价格,通过后期供水利润弥补前期亏损。     

水价调整的两大误区

近年来,各地水价纷纷上涨。调整水价成为政府与公众关注的焦点。目前,水价调整出现了一些误区,可能影响人民生活水平的改善与供水行业的发展。本文对两个误区进行了分析,认为欧洲国家城市居民生活水费支出占总支出远没有达到3%,北京市市城镇居民水费支出占总支出的比例不是1%,而是1.5%以上。建议我国城市在提高水价的同时,应改善供水水质,提高供水企业效率。     

三峡库区典型移民小城镇给排水现状调查和居民用水情况研究

针对三峡库区移民安置形成的诸多移民小城镇给排水设施和用水状况的变化,以重庆市忠县石宝镇为例,调查了镇区给排水现状和居民用水情况.调查结果表明:石宝镇给排水基础设施比较完备,但是供水水质、污水处理率和处理效果均有待提高.常规的居民家庭卫生和用水设备比较齐全,但大用水量的设备较少;城镇居民的人均用水量较小,仅为40.1～74 L/d,远低于相关规范的设定值.室内有给排水卫生设备和淋浴设备是镇区最为普遍的用水模式.不同季节的居民各项用水支出在用水总量中的比例差别较大.影响当地居民生活用水量的主要因素是人口、经济条件、水价和气候温度.     

新疆石河子市居民生活用水水价研究

对石河子市居民支付水费情况、居民对水价的承受能力进行了调查分析,从结果看出:目前石河子市的居民生活用水水价还在居民的承受能力范围内,水费支出也在居民的承受力内。采用水资源价值模糊数学模型对石河子市水价进行了计算,得出了该市居民生活用水合理的价格范围为1.95~2.70元/m3。     

南水北调中线工程用水户水价承受能力分析

根据南水北调工程近期供水的目标,对工程受水区各主要城市居民生活用水和工业用水的水价承受能力进行了分析。结果表明,目前受水区各主要城市居民生活用水和工业用水的水价总体偏低,有较大提价空间;但各省市最低收入居民对测算的中等收入居民的生活用水水价较难承受,建议建立定额用水制度,在总体水价不降低的前提下减少低收入群体的水费支出。     

2003年兰考、东明洪水漫滩落淤情况调查

通过对2003年秋汛期间兰考北滩、东明南滩两处漫滩情况进行调查与分析，得出的结论为：滩区共滞蓄水量6亿～9亿m^3，漫滩落淤范围为7．5km^2，顺漫滩水流方向的落淤距离约3km。在这种水沙条件下，泥沙不能被输送至较远的堤河。经分析计算，本次泥沙落淤量为900万～1350万t，且距口门1．0km范围内落淤泥沙中的82％为粒径大于0．05mm的粗沙。由此得到的主要认识有：①靠自然落淤解决“二级悬河”问题非常困难，甚至会增大“二级悬河”程度；②给漫滩水预留出路是降低淹没损失的关键；③落淤的粗沙使土地产生了十分严重的沙化现象，并且使当地环境趋于恶化。     

雷州半岛地区2015年防旱抗旱工作对策与启示

2015年,广东省雷州半岛地区出现大范围干旱,该文总结了干旱特点,分析了干旱成因,采取了水资源统筹调配、引导调整种植结构及播种时机、人工增雨、筹措资金应急补助等抗旱措施,效果较好。此外,提出该地区今后打造"扩库硬渠上井群"升级版、推进农业结构调整、改善生态环境推动绿色发展的防旱工作对策。     

山西省地下水资源开发利用中存在的问题及对策

山西省水资源严重短缺 ,地下水超采严重。分析了地下水资源量及可开采量、地下水开发利用历史和现状 ,以及超采产生的环境地质问题。在此基础上 ,提出了缓解地下水超采、有效合理开发利用地下水的一些措施意见 ,为加强地下水保护和管理提供了科学依据。     

Operation and Maintenance Performance and Conflicts in Flood-control Projects in Bangladesh

Many embankments failed in severe floods in Bangladesh in 1987 and 1988, and concern grew over ways to improve flood-control projects. Maintenance was poor due to reliance on periodic rehabilitation, but few failures were due to poor construction or maintenance. Embankments mostly failed where they were eroded or were deliberately cut. They were cut by people living outside who believed they were made more flood-prone, and by people living inside because of internal drainage congestion. This reflected inadequate hydrological modelling, lack of consultation and failure to resolve conflicts between affected groups. Resources for maintenance are not generated locally and could be used more efficiently. Participatory planning could reduce conflicts, encourage a sense of project ownership and facilitate contributions to maintenance.     

南京市2016年暴雨洪水分析与思考

2016年汛期,南京市发生了建国以来的大洪水,降雨量和主要河湖水位均超历史.在对2016年暴雨、水情、洪水特点分析的基础上,提出加强南京市防洪工程体系的建议.     

Domestic Water and Sanitation in Cyclones and Floods in Bangladesh and a Proposed Research Agenda

ABSTRACT

Water is one of the top priority item s i relief activities but the appropriateness and effectiveness of this activity may be questioned. Water and sanitation (WS) are inseparable and together they play major roles in the transmission of the pathogen of diarrhoeal disease. Thousands of people die or suffer from WS-related diseases during postdisaster periods. Here we present WS-related experiences gained after Bangladesh's 1991 cyclone and the views of participants in a regional and a national (local) workshop on this matter held in Bangladesh. About 63 per cent of the water purifying tablets (WPTs) distributed after the 1991 cyclone were found to have lost potency Relief personnel lack basic knowledge about WS practices and the management of WS provision. Participants in the two workshops documented serious problems i this field at both regional and national levels. Major issues for research may include: an appropriate environmental preparedness plan; appropriate waste disposal technologies; appropriate water treatment methods; self- help activities during vulnerable periods; and health education related to WS in disaster situations.     

Progress in ecological and environmental water requirements research and applications in China

Abstract:

With economic development, as well as population growth, the conflict between water supply and demand has become more and more acute in China, and it has been aggravated further by the irrational utilization of water resources. As a result, the deterioration and destruction of the eco‐environment have become increasingly serious. In order to effectively protect ecosystems and improve their ecological conditions, many studies on ecological and environmental water requirements (EEWR) have been carried out in China. In this paper, the concept and characteristics of EEWR are addressed, and the main advances of EEWR research and applications in China are summarized in four types of systems including studies on rivers, vegetation, lakes and wetlands, and groundwater. In conclusion, issues necessary to be studied further in the future are put forward.     

Distribution and removal of Giardia and Cryptosporidium in water supplies in Germany

This study has been conducted, to estimate the distribution of Giardia and Cryptosporidium in German water supplies and the removal efficiency of surface water treatment plants for Giardia and Cryptosporidium by conventional treatment. Water samples from six surface water treatment plants in different parts of Germany were simoultaneously examined for Giardia and Cryptosporidium. Investigations for both parasites were carried out in the period from July 1993 until December 1995. The results confirmed the occurrence of Giardia and Cryptosporidium in surface and raw water, to intermediate steps after treatment, in back wash water, in the first filtrate and in final water. Giardia or Cryptosporidium or both have been found in 76.2% of the investigated raw water sources. The average number of the detected Giardia cysts was 88.2/100 1 (max.1314/100 I), and the average number of Cryptosporidium oocysts was 116/100 I (max. 1081/1001). In the intermediate steps (including flocculation and several steps of filtration), Giardia or Cryptosporidium or both have been found in 33.3% (50/150) of the samples. 14.9% of drinking water samples (7/47) were positive for Giardia (max. 16.8 /1001) and 29.8% (14/47) were positive for Cryptosporidium (max. 20.8/100 I). Overall, Giardia and Cryptosporidium, or both were detected in 38.3% of the drinking water samples. The parasites have been found in nearly all of the investigated backwash water samples. The filtrate of a rapid sand filter was analysed immediately after filter backwashing during the ripening period of the filter. Good elimination results were obtained by optimizing relevant water treatment process, but a low flocculant dose following sudden variation in the raw water quality, causes a breakthrough of Cryptosporidium into the treated water. Although water treatment technologies are effective to remove Giardia and Cryptosporidium, the results clearly show that Giardia and Cryptosporidium evade the filter harries m the absence of visible treatment deficiencies and low turbitidy level, and contaminate final water.     

我国灌区建设及管理技术发展成就与展望

新中国成立70年来,我国灌区建设与管理取得了举世瞩目的成就,农田灌溉面积由1949年的1593万hm2发展到2016年的6714万hm2,位列世界第一,保障了我国粮食安全供给和社会经济发展。我国灌区建设与管理已经历了三个大的发展阶段,依靠科技进步解决了发展过程中出现的各种问题,使我国灌区建设与管理水平逐步得以提升。今后的30年将是我国实现灌区现代化的时期。本文较系统介绍了我国灌区发展概况、灌区建设与管理技术进展和成就、灌区面临的主要问题和挑战、以及灌区现代化发展展望。