涌泉灌技术在陈庄果园的应用

过临猗县闫家庄镇陈庄果园试点,对用涌泉灌、滴灌及微喷灌三种微灌技术进行比较,结果表明涌泉灌具有抗堵塞能力强、投资少、管理方便、使用寿命长等优点,应予优先推广     

灌区工程老化损坏程度综合评判模型

应用模糊集合理论建立了灌区工程老化损坏程度综台评判模型。该模型在我省44处大中型灌区中进行了计算,根据计算成果对所评定的灌区工程进行了老化损坏程度排序及等级划分。     

小河口灌区可持续发展对策初析

从小河口灌区的水源工程、渠系工程、田间灌溉管理现状分析入手，提出了适合灌区可持续发展的初步对策。     

水资源供需分析中的几个问题

本文结合县级水资源开发利用现状分析工作实际，论述有关农业灌溉需水量、可供水量和供需平衡的计算，举出实例阐明某些重要基本概念。     

Analytical integration of the equation of gradually varied flow for triangular channels

The solution of the gradually-varied-flow equation allows the tracing of the flow depth along a channel length. No closed-form solution is available in the technical literature for this differential equation for triangular channels based on Manning’s formula. In current research, by applying Manning’s formula, an analytical solution to compute the length of the gradually-varied-flow profile for triangular channels is derived. Moreover, the dimensionless profiles for subcritical and supercritical flow in both a mild slope and a steep slope triangular channel are presented. Finally, using the proposed solution, the computation steps of the discharge for a given triangular channel are presented. The direct solution presented in this study can be used for triangular irrigation ditches and triangular channels.     

节水灌溉控制中远程信号变送器的研究与设计

针对电压信号不适合远距离传送的特点,结合农业节水灌溉控制的实际情况,筛选并设计出以集成运算放大器为核心的电压转换为电流的变送器及以集成芯片LM331为核心的电压转换为频率、频率转换为电压的变送器。经在农业节水灌溉控制工程中应用,可以满足信号远距离传送的要求,并且性价比较高。     

Can Sub-Saharan Africa feed itself? The role of irrigation development in the region’s drylands for food security

ABSTRACT

This paper assesses the potential role of investments in irrigation in Sub-Saharan Africa in improving food security and self-sufficiency in the region. Focusing on the region’s drylands, the study identifies a potential for expanded irrigated area of 6–14 million hectares (ha), depending on technology costs and other factors. Linkage of these results with a global agricultural trade model shows that accelerated irrigation investment can effectively reduce growing food import dependency from 54% under a business-as-usual scenario to a much smaller 17–40%; and can also reduce the population at risk of hunger and child under-nutrition.     

Lake Turkana,major Omo River developments,associated hydrological cycle change and consequent lake physical and ecological change

This study aimed to explore Lake Turkana's ecological reliance on hydrology and to determine the hydrological changes and consequences arising from the major hydropower and irrigation developments in the lake's basin. The major developments on Ethiopia's Omo River are especially significant as this river provides over 80% of the lake's annual freshwater influx and associated nutrients. The cascade of hydropower dams permanently dampens the natural hydrological cycles and lake level variability. The driving force of the flood influx to the lake is curtailed and the pattern of lake currents will adjust. Ultimately 80% of the river inflow to the lake will be regulated. Large volumes of water are required to initially fill the hydropower dam reservoirs. During 2015–16 when the huge Gibe III reservoir was filled, Lake Turkana's water level declined 2?m.The study has shown that large-scale irrigation schemes in the Lower Omo can potentially abstract 50% of the Omo River water, and that this would cause the lake level to shrink permanently to the detriment of the lake ecology. Possible lake level drops of over 15?m are demonstrated. The basin's natural capital is being replaced by large-scale plantation developments. The hydrological changes are drastic and the ecological consequences on Lake Turkana have not been fully understood. Without serious mitigation measures, Lake Turkana is a potential African Aral Sea disaster in the making, emulating what has happened to other great lakes such as Lake Chad.     

The Research of the Tidal Irrigation SystemBased on the Mobile Seedbed

Tidalirrigationis a use forthe realization of the principle of capillary irrigation techniques from plant roots. This technique could avoid generating water film on blade surface, let blades to receive more sunshine and advance photosynthesis efficiency; Increasing the utilizationrate of water and fertilizer;Providing manageablerelative humidity and reducing the plant diseases and insect pests. But for now, domestic research on related technologies is less, and the overall level is relatively backward, and the number of research papers related to the number of patents is low.Based on this situation, the efficiency of irrigation and water absorptionwould be evidently increased, and the utilization rate of nitrogenous fertilizer could be reduced by strengthening the research of tidalirrigation system and putting the system into the greenhouse. This computer-based control to achieve crop irrigation and fertilization system, will have broad application prospects.     

膨润土防渗毯渠道衬砌防冻胀试验研究

为了解决宁夏灌区渠道衬砌冻胀破坏严重的技术难题,研究了适应冻胀的柔性新材料——膨润土防渗毯衬砌结构在渠道衬砌上的应用,并选取典型渠道铺设防渗毯开展了防冻胀试验研究。对气温、地温、冻深、冻胀量、土壤水分等冻胀指标的观测结果表明:防渗毯没有抵御冻胀的能力,但适应冻胀的能力较强,同时具有自修复功能和自愈合能力,施工简单,不受环境限制。此外,还对采取素土加防渗毯结构应具备的条件和措施进行了探讨。