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Quality issues in harvested rainwater in arid and semi-arid Loess Plateau of northern China 总被引：1，自引：0，他引：1
Kun Zhu Linus Zhang William Hart Mancang Liu Hui Chen 《Journal of Arid Environments》2004,57(4):487-505
Loess soils cover vast areas in the arid and semi-arid regions of northern China. Due to the lack of reliable surface water and ground-water, rainwater harvesting has played a prominent role in farmers’ domestic usage and agricultural irrigation. An economical and valid type of water storage cistern with optimum design of components has been introduced to rural areas in the Loess Plateau. Different collection alternatives showed apparent variations in rainwater quality. By using different catchments, such as mortar roofs and cement-paved courtyards, compacted land or road surfaces, rainwater can be effectively collected for storage in cisterns. This study focused mainly on the quality of rainwater harvested from the different catchment systems and stored for different periods of time. By analysis of the water samples stored in these cisterns, it was evident that rainwater quality could be improved significantly by self-purification during the storage. With emphasis on rainwater quality affected by the different catchment systems, it was found that the measured inorganic compounds in the rainwater harvested from roof-yard catchment systems generally matched the WHO standards for drinking water, while the concentrations of some inorganic compounds in the rainwater collected from land and road surfaces appeared to be higher than the guideline values for drinking water, but generally not beyond the maximum permissible concentrations. However, Fecal Coliform, which is an important bacteriological parameter for the three catchment systems, exceeded the limits of drinking water to a greater extend. Trace amounts of 55 organic pollutants were identified, including aliphatic hydrocarbons, aromatic compounds and phthalate esters, etc. The analytical results indicated that roof-yard catchments that included the “first flush” usually provided safe drinking water with low organic contents, even for rainwater collected immediately after rainfall. In contrast, rainwater harvested from road surfaces had poor quality with respect to the organic constituents, regardless of stored time. 相似文献
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Tunisia is a marginal country hydrologically and it has adopted a number of distinctive methods of water management for agriculture. The central region supports modern dam irrigation, whilst traditional rainwater harvesting is practiced in the south. These contrasting techniques are described and evaluated in terms of sustainability using empirical field data and secondary literature for two study sites. Research focuses primarily on the physical environment, but socio-cultural and economic viability are also examined. Analysis indicates that traditional water management advantageously partitions the continuum dividing hazards and resources through subtle manipulation of the environment. A potentially hazardous environment is rendered secure by resourceful water management based on community action and cumulative knowledge. This practice minimizes community dependency and local economic imbalance. With dam irrigation, carrying capacity is established more forcibly by centralized control in order to place society within world markets. An almost total break from environmental variability is made in the short term, but this can lead to disequilibrium over longer durations. Additionally, the spatial and social distributions of development are uneven. In Tunisia, maintenance of traditional methods can reduce the negative impacts caused by modern programmes and support their positive characteristics. A mix of both methods offers a foundation to sustainable water supply in the new millennium. 相似文献
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利用水量平衡原理,基于流域水资源量及水资源利用水平、灌溉定额等资料,计算探讨了塔里木河流域“四源一干”现状水平年（2010年）和规划水平年（2020年、2030年）可承载灌溉面积、不同来水频率下规划年灌溉面积超载和生态水保证情况。结果表明：（1）现状水平年,流域可承载灌溉面积为129.06×104 hm2,除和田河流域外其它区域均超载,超载面积为41.7×104 hm2。（2）2020年,25%来水频率下,除开都-孔雀河流域其他区域均不超载。在50%与75%来水频率下,流域规划灌溉面积超载较大,分别为10.21×104 hm2与28.05×104 hm2,管理部门应对规划方案进行科学论证。75%来水频率下,流域生态水保证率为76%,表明枯水期生态水供应存在压力。（3）2030年,25%来水频率下,除开都-孔雀河流域其他区域均不超载。在50%与75%来水频率下,流域规划灌溉面积超载较大,分别为7.06×104 hm2与24.09×104 hm2。75%来水频率下,流域生态水保证率为81%,表明枯水期生态水供应仍然存在压力。研究结果为流域水资源配置及区域可持续发展提供了重要数据支撑与理论依据。 相似文献
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Rainwater-harvesting tanks (reservoirs) in Tamil Nadu, India support agricultural livelihoods, mitigate water insecurity, and enable ecosystem services. However, many tanks have fallen into disrepair, as private wells have supplanted collectively managed tanks as the dominant irrigation source. Meanwhile, encroachment by peri-urban development, landless farmers, and Prosopis juliflora has reduced inflow and tank capacity. This exploratory study presents a conceptual framework and proposed indicator set for measuring water security in the context of rainwater harvesting tanks. The primary benefits of tanks and threats to their functionality are profiled as a precursor to construction of a causal network of water security. The causal network identifies the key components, causal linkages, and outcomes of water security processes, and is used to derive a suite of indicators that reflect the multiple economic and socio-ecological uses of tanks. Recommendations are provided for future research and data collection to operationalize the indicators to support planning and assessing the effectiveness of tank rehabilitation. 相似文献
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新疆水资源可持续利用的战略对策 总被引：19，自引：4，他引：19
通过总结和分析新疆水资源利用中的问题，提出实施水资源可持续利用战略，实施可持续水利建设，实施综合性水资源管理及发展节水型产业和建立节水型社会是实现新疆水资源可持续利用的战略对策和措施。 相似文献
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《地理学报(英文版)》2019,(3)
The Interconnected River System Network (IRSN) plays a crucial role in water resource allocation, water ecological restoration and water quality improvement. It has become a key part of the urban lake management. An evaluation methodology system for IRSN project can provide important guidance for the selection of different water diversion schemes. However, few if any comprehensive evaluation systems have been developed to evaluate the hydrodynamics and water quality of connected lakes. This study developed a comprehensive evaluation system based on multi-indexes including aspects of water hydrodynamics, water quality and socioeconomics. A two-dimensional (2-D) mathematical hydrodynamics and water quality model was built, using NH_3-N, TN and TP as water quality index. The IRSN project in Tangxun Lake group was used as a testbed here, and five water diversion schemes were simulated and evaluated. Results showed that the IRSN project can improve the water fluidity and the water quality obviously after a short time of water diversion, while the improvement rates decreased gradually as the water diversion went on. Among these five schemes, Scheme V showed the most noticeable improvement in hydrodynamics and water quality, and brought the most economic benefits. This comprehensive evaluation method can provide useful reference for the implementation of other similar IRSN projects. 相似文献
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引黄灌区节水灌溉分区与节水途径初探 总被引：6，自引：2，他引：4
依据气候、地形、地貌、土壤、植被、地质等自然地理条件的基本一致性、水资源条件基本相似、水资源利用水平大体相当、农业自然条件和作物布局基本一致、经济发展水平大致相当和照顾行政界限、流域边界等固有分区等 6个基本原则 ,将黄河流域引黄灌区节水灌溉分为河源至兰州、兰州至河口、河口至龙门、龙门至花园口、花园口至河口等5个大区 ,并对各分区的基本特点和节水灌溉的发展方向和主要途径作了深入的分析. 相似文献
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新疆实施参与式灌溉管理的对策和建议 总被引：2，自引：2，他引：2
新疆农业的发展完全依赖于引水灌溉事业的发展与有效管理。农民参与灌溉管理是当今世界各国灌区管理机制改革的一个热门话题。世界上有许多中小型灌区已经成功地实施了参与式灌溉管理。参与式灌溉管理于20世纪90年代初随着世界银行贷款项目传入我国，并取得了初步的成果和经验。新疆结合世界银行贷款“塔里木盆地灌溉与环保二期工程”项目，分别在其五个子项目区建立了建立经济自立灌排区，开始进行参与式灌溉管理的试点工作。本文通过对参与式灌溉管理的基本模式、新疆的灌溉管理问题及实施参与式灌溉管理的内外部条件的分析，提出了新疆实施参与式灌溉管理的对策和建议。 相似文献
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内蒙古河套灌区水盐平衡与干排水脱盐分析 总被引：13，自引：2，他引：11
内蒙古河套灌区由于气候和水文地质条件影响,外排水不畅,地下水位超过临界水位,土壤次生盐渍化严重,河套灌区续建配套和节水改造是防治土壤盐渍化根本工程措施。根据1987~1997年期间的水盐均衡计算,河套灌区,整体处于积盐过程。灌区荒地和低洼湿地有排水积盐作用,从而减轻耕地盐渍化,通过蒸发,可积聚进入灌区盐分的65%。这种干排盐技术,可作为灌区农田土壤盐渍化脱盐的一项重要措施。调整河套灌区种植结构,选择耐盐作物品种种植,可起生物排盐作用,增加土壤有机质,抑制土壤积盐。 相似文献
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半干旱区雨水集流研究进展及其现状 总被引：24，自引：5，他引：19
论述了国内外半干旱区雨水集流研究的发展和存在问题。国外雨水集流研究的发展可分为三个阶段:20世纪50年代以前为雨水的初始利用阶段;20世纪50年代到80年代为基础性研究和技术开发大发展阶段;20世纪80年代以后为系统研究阶段。国内雨水集流研究相对较晚,20世纪60年代为初步研究阶段,20世纪80年代以后为系统研究阶段。集水技术操作简单,适应性强,费用低,开发潜力大,从事的生产领域广泛,采用这种技术可以建立新的农业生态系统并改善半干旱区生态环境。 相似文献
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兰州南北两山植被恢复策略 总被引：8，自引：0，他引：8
兰州地处黄土高原最西端、降水量仅320 mm,但蒸发量1 500 mm,干旱是植被恢复建设的制约因子。如何利用南北两山的地形和黄河流经兰州的天然优势,利用当地的降水和适当的补充灌溉,恢复南北两山植被,是个急需解决的科学问题。在分析兰州市南北两山植被恢复的历史、经验教训及相关研究成果的基础上,探讨了南北两山植被建设的策略。提出在遵从植被与气候耦合的生物地带性生态规律的基础上,以乡土植物,配合雨水集流等补充灌溉,创造斑块状乔灌木植被,是实现该地区的植被恢复、重建和稳定的重要途径。 相似文献
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灌区渠系特征与灌溉水利用系数的Horton分维 总被引：1，自引：0，他引：1
灌区渠系和自然河流水系存在着诸多相似之处,因此,对于灌区渠系体系是否存在及在何种程度下满足Horton 河系定律值得研究。以2010 年广东省53 宗样点灌区为研究对象,分类进行了适用性分析,发现只有四级渠系类灌区满足Horton 河系定律。在此基础上计算了各级渠系类灌区的渠系特征参数和分维值,并利用2007-2011 年实测数据,对其与灌溉水有效利用系数之间的作用关系进行了定性和定量分析,结果表明：渠系工程状况参数（0.1084） >下垫面参数（-0.3554） >渠系结构参数（-0.5189） >面积尺度参数（-0.5392） >渠系分维特征参数（-0.5536）。本研究对于定量表征灌区形态和渠系特征对灌溉水有效利用系数的影响提供了新的途径,研究结果对于指导灌区渠系规划建设,提高用水效率具有积极现实意义。 相似文献
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黑河“97”分水方案适应性分析 总被引：2，自引：0，他引：2
黑河“97”分水方案自2000年实施以来,流入下游水量明显增加,缓解了下游生态环境恶化趋势,但在丰水年难以完成分水指标,其适应性受到各方关注。本文在分析“97”分水方案的技术特点及背景条件变化对分水方案适应性影响的基础上,通过构建黑河水资源配置模拟模型,对分水方案在不同需水条件和黄藏寺水库建成运行后长系列年（1958-2012年）实施情况进行了模拟,分析评价了黑河“97”分水方案的适应性。研究表明,由于分水方案制定和实施前后黑河经济社会、水系连通性等背景条件发生了较大变化,在现状工程和需水条件下,不能完成“97”分水方案的分水要求;在中游退耕至2000年水平和黄藏寺水库建成的情况下,虽然可以完成“97”分水方案的分水要求,但仍存在地下水超采情况,因此,基于20世纪80年代中期黑河经济社会和1955-1986年水文条件的“97”分水方案与黑河流域现状存在一定的不适应性。 相似文献
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An understanding of the differences in artificial forest between tree species, slope aspects, and management options in arid environments is fundamentally important for efficient management of these artificial systems; however, few studies have quantified the spatial and temporal differences in stem radial growth of trees in the arid western Loess Plateau of China.Using dendrochronology, we assessed the growth of three woody species(the native shrub Reaumuria soongorica, the exotic shrub Tamarix ramosissima and tree Platycladus orientalis) by measuring the annual stem radial increment. We also describe the long-term growth trends and responses to climatic factors on slopes with different aspects during periods with and without irrigation. We found that precipitation during the main growing season was significantly positively correlated with ring growth for all three species and both slope aspects. In addition, supplemental water(e.g., irrigation, rainwater harvesting) greatly relieved drought stress and promoted radial growth. Our results suggest that as the main afforestation species in the Loess Plateau used for soil and water conservation, P. orientalis is more suitable than T. ramosissima under rain-fed conditions. However, a landscape that combined a tree(P. orientalis) with a shrub(R. soongorica) and grassland appears likely to represent the best means of ecological restoration in the arid western Loess Plateau. 相似文献
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以山东省临沂市东风东关片区改造为例,将海绵城市建设要求融入到园林景观建设中。通过对临沂当地降雨量的分析,制定区域降雨控制管理目标,采取了屋顶绿化、透水铺装、下凹式绿地、植草沟、渗井渗管、车库顶板处理、雨水回收利用系统和植物绿化等措施。雨水回收利用系统工程完成后,通过夏季的几场大到暴雨的检验,实现降雨后片区道路雨水下渗明显、无积水,基本达到规划设计的目标要求,该方法将有助于海绵城市在临沂市的推广应用。 相似文献
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兰州南北两山生态环境脆弱,自然状态下无法达到城市发展的绿化要求,必须进行生态环境建设。针对生态环境建设的决策困境,提出构建“决策支持系统+专家知识”的决策支持模式。在详细阐述此决策支持模式的基础上,以兰州南北两山作为研究案例,建立了兰州南北两山生态环境建设决策支持系统,通过该系统的试验结果讨论,最终给出兰州南北两山生态环境建设的两项用水措施建议,即： ①在多年平均降雨量大于400 mm的区域进行人工集雨;②在多年平均降雨量小于400 mm的区域进行人工灌溉(灌溉量相当于200 mm降雨)。最后结合专家知识形成兰州南北两山生态环境建设规划图,供决策者参考。 相似文献
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甘肃秦王川灌区农业节水途径探讨 总被引：2，自引：0，他引：2
甘肃秦王川灌区水资源紧缺,兰州新区城镇化建设加速水资源消耗趋势,使灌区水资源供需矛盾日渐突出,农业节水势在必行。根据中国西北干旱地区农业节水取得的成效和灌区农业生产节水试验,提出适宜于秦王川灌区农业节水的5条具体途径:①发展以地面灌溉为主的先进灌溉技术;②渠道衬砌;③农业节水技术与地膜覆盖栽培技术相结合;④推行膜下滴灌技术;⑤倡导节水文化,共建节水型社会。通过这些农业节水技术的实施,使秦王川灌区从简单的农业灌溉,转变为农业、城乡生活、生态、工业等多元用水格局,促进灌区经济可持续发展。 相似文献