浅析赣抚平原灌区水资源管理现状、问题和对策

详细分析了赣抚平原灌区水资源现状及存在的问题,提出了相应的对策和措施.     

潦河灌区发展方向的思考

江西省潦河灌区工程是农业基础水利设施,属公益性的水利设施,历经多年运行,逐渐在工程建设、机构管理、工程运行及用水管理、机构运行经费来源等各方面出现诸多影响灌区发展的问题,本文对潦河灌区今后发展方向进行了思考,并指出今后灌区可持续性的发展离不开政府的支持与扶持.     

基于SWAP模型的河套灌区向日葵农田土壤水盐通量模拟

为了探究河套灌区节水实施现状条件下农田土壤水盐动态变化规律,利用向日葵田间试验观测资料,对SWAP模型进行参数率定和验证,并利用该模型模拟向日葵生长条件下0～100 cm土层土壤水盐通量及水盐平衡状况。研究结果表明：在灌溉阶段,向日葵根系层土壤水分主要向下渗漏,水分通量和盐分通量为负,土壤盐分被淋洗;在非灌溉阶段,地下水向上补给向日葵根系层土壤,水分通量和盐分通量为正,根系层土壤积盐。2019、2020年模拟期间水分通量累计量分别为52.5、60.6 mm,盐分通量累计量分别为-4.5、-4.9 mg/cm²,0～100 cm土层土壤盐分通量分别增加了7.5、7.1 mg/cm²。向日葵现状灌溉条件下0～100 cm土层土壤积盐,可能产生土壤次生盐碱化的风险,向日葵生育期结束后需要进行秋浇淋洗盐分来保证下一年度向日葵的正常生长。     

Experimental and numerical analysis of a tube-type networked solar still for desert technology

A tube-type solar still is proposed to integrate a conventional still and a water distribution network suitable to our concept of desert plantation. This still is directly set up on ground-like pipelines connecting brackish water or seawater ponds. The distilled water is immediately supplied to the plants under the ground by penetration without any extra water pipelines. The still is made of metal-free materials, e.g., plastic as vinyl chloride or PET resin which are inhibited from corrosion by seawater. Experimental data measured in our laboratory using infrared lamps showed the effectiveness of the method for productivity, the design of the basin tray and thermal efficiency up to 12.5%. Numerical simulations with experimental data as the temperature profiles at the tube walls estimated heat convection occurring within the still for modification of the Dunkle's model. Active convection over the basin was predicted in the half-cut tube type of the basin as compared with a conventional flat basin. The secondary convective circulations under the basin in case of the flat basin promote bulk flow from the upper part of the basin to the lower part, which suggests the necessity of insulating the lower part of the still. On the other hand, the tube basin enlarges the evaporative area over the basin and restricts the vapor circulation under the basin. Simulated results show that the performance of this type is not necessary for the insulation of a still and possible for setting up the lower part of the still under the ground. The tube-type solar still is very simple and has been researched, but further research is needed to make it a suitable technology for desert plantations.     

Qualifying irrigation system sustainability and governance by means of stakeholder perceptions: the Neste Canal (France)

From the analysis of stakeholders’ attitudes, this article explores problems, opportunities and constraints for improving sustainability and establishing better water governance processes in the selected case study, the Neste irrigation canal (France). Data were collected through semi-structured interviews and analyzed by means of a new codification system for identifying the affinities and confrontations between stakeholder demands. Results revealed that there are conceptual and practical heterogeneities among the preferences of stakeholder groups regarding irrigation management, sustainable attitudes and governance promotion. These results can be used by stakeholders and the relevant authorities as a first step in customizing their interventions.     

A soil water and solute learning system for small-scale irrigators in Africa

Abstract

Better yields of high-value crops are necessary for a profitable irrigation industry in sub-Saharan Africa. We introduced two simple tools, the Chameleon soil moisture sensor and the FullStop wetting front detector, which represent soil water, nitrate and salt levels in the soil by displaying different colours. These tools form the basis of an experiential learning system for small-scale irrigators. We found that farmers quickly learned from the tools and changed their management within a short time. The cost of implementing a learning system would be a small fraction of that of building or revitalizing irrigation schemes.     

Pipeline Contactor Design and Retrofit Fundamentals

Utilities with existing air system and aging ozone generating equipment are considering replacing generators capable of producing 1 to 2% ozone in air with those capable of producing ozone at 12% in oxygen. However, higher ozone weight percentage results in lower gas flow, issues with gas flow control, poorer mixing in the transfer cell of a conventional contactor, and oversized ozone destruct blowers, thereby requiring redesign of several subsystems within the ozone process. This document describes three retrofit experiences with installing (1) high concentration ozone generating equipment on a system formerly designed for air, (2) a sidestream injection system in an existing pipeline, and (3) a new pipeline contactor.     

漳河水库灌区水资源脆弱性评价研究

依据漳河水库灌区水资源现状,采用AHP方法,建立了水资源脆弱性评价指标体系和水资源脆弱度评价阈值,分析了灌区自然脆弱性、人为脆弱性和承载脆弱性等敏感指标,并用2005年实际资料对灌区脆弱性水平进行了评价.结果表明:水资源脆弱性综合评价阈值G=3.05,处于中等脆弱态势;自然脆弱性G1=1.41,处于较强脆弱态势;人为脆弱性G2=3.94,处于不脆弱态势;承载脆弱性G3=3.00,处于中等脆弱态势,与实际情况基本吻合.     

河北石津灌区水循环组份特征及用水水平分析

选择河北省石津灌区作为研究区,利用收集的灌区资料分析灌区2004~2006年水循环组份特征,发现灌区水资源组成结构中灌溉和降雨所占比例为42%,潜水补给所占比例为16.5%,灌域降水量、潜水位和作物腾发量年内变化皆表现出了一定的规律性.选择渠系水利用系数、灌溉效率以及3个水分生产率指标计算了2004~2007年冬小麦生育期内灌区用水水平,结果表明渠系水利用系数和灌溉水利用系数2004~2007年平均值分别为0.51和0.4,而考虑了水资源在时间上的重复利用后,得到灌溉效率为0.66,通过计算灌域不同尺度水分生产率,发现该指标随着尺度的增大而减小,说明水平回归水很少.     

宁夏灌区末级渠系衬砌现状与破坏 原因分析研究

宁夏灌区末级渠系面广量大,位于季节性冻土地区,渠道衬砌往往破坏严重,影响了正常的渠道输水和安全运行。本文在对灌区末级渠系现状全面调查的基础上,根据衬砌破坏程度对渠道的破坏类型进行了划分,对破坏原因进行了研究分析。研究结果可作为灌区渠道设计的依据,也可为灌区节水工程改造和渠道衬砌工程的建设提供技术支撑。