管道输水灌溉技术

管道输水灌溉技术目前已成为世界农业节水灌溉的一项关键技术。由于管道输水灌溉投资少，节水效益显著，近20年来我国管道输水灌溉发展较快，但还远不适应农田灌溉对节水的要求。我国北方灌区现有井灌面积1133万多公顷，管道灌溉面积还不到1／3，大面积的提水和自流灌区仍以明渠输水灌溉为主。但目前管道输水灌溉的标准较低，影响了节水灌溉的水平。因此，我国的农田遭溉还存在较大的节水潜力，作为节水灌溉主要措施之一的管道输水边溉技术将面临更广阔的发展前景。1管道输水灌溉系统的组成作为完整的节水灌溉系统，管道输水灌溉系统应该包…     

黄河上中游大型灌区推广管道输水发展节水灌溉的可行性分析

通过对黄河上中游水资源特点及大型灌区目前存在的主要问题的分析，结合管道输水灌溉技术特点及目前国内外发展概况，提出了黄河上中游大型灌区推广管道输水发展节水灌溉的思路，并通过试验示范工程进行了技术经济论证。同时认为黄河上中游大型灌区推广管道输水发展节水灌溉具有有利的条件，节水效益十分显著，对解决该区水资源供需矛盾，促进当地工农业持续稳定发展，以及缓解黄河中下游的水危机具有重大的战略意义。     

简讯

薛城区大兴农田水利管道输水灌溉工程山东省枣庄市薛城区重视推广先进的、科学的水利技术,大力发展农田水利节水、管水、灌溉新技术,1990年以来,区水利局坚持以“重点、质量、效益”为中心,以“开源挖潜、节水”为重点,发展全区的水利工作,大兴管道输水灌溉的节水工程,并把大干农田水利、加强水利工程管理、发展水利当作重要工作抓紧抓好。一年来全区共投资785.9万元,投劳214万工日,完成土石方178万 m~3,新打机井325眼,铺设各种输水管道138条计11.9km,增加和改善灌溉面积6.37万亩,为农业的丰产创造了条件。为全面推广管道输水灌溉等先进技术,该区还组织人员分期分批赴北京等地学习。投资10万元兴建了两处混凝土制管厂,为低压管道输水灌溉提供了新型的管道材料。1990年底该区被枣庄市水利系统评为推广管道灌溉先进区并获一等奖。     

我国节水灌溉发展面积现状与宏观效益分析

对我国工程节水灌溉(防渗渠道输水灌溉、低压管道输水灌溉、喷灌、微灌、雨水集蓄工程节水灌溉)和非工程节水灌溉(水稻节水灌溉、坐水种等)面积发展状况作了简要总结，对其宏观效益作了扼要分析。     

常见农业节水技术特点及节水工程建设中的几个问题

总结了地面灌溉、管道输水、渠道防渗、喷灌技术、微灌技术、农艺节水灌溉等几种常用农业灌溉节水技术特点及适宜条件,通过对大力发展农业节水工程的重要性、节水投入体制、项目管理方式、工程管理措施、节水体系建设等问题的探讨,提出大力发展适应我国农村现状的节水灌溉技术。     

一种农用低压水泥管闸阀的研制

为解决节水灌溉使用低压管道中配套工业用闹闹不合理问题，研制一种与低压水泥沙土管相配套的低压水泥管闹闹，以降低工程投资，促进低压管道输水灌溉发展。     

利用低压输水系统进行二次加压喷灌的尝试

１问题的提出低压管道输水灌溉（以下简称管灌）工程作为一种节水灌溉方式,发展迅速。这种灌溉方式极易被人们所接受的主要原因有：造价低、占地少、施工简单、使用方便和出水量大。但由于土壤、水源以及灌溉习惯等因素的影响,瓦房店市管道输水的田间水利用率并不高,不足以达到高效用水的目的。因此管道输水不能成为本地发展节水农业的主导灌溉形式。随着节水灌溉的发展,喷灌以它节水效果明显、适应性强、可提高产量等特点,将成为发展现代农业的首选灌溉方式。为了提高田间水利用率,降低工程造价,提出利用低压管道输水进行二次加压喷…     

农村实用节水灌溉技术

一、低压管道输水灌溉技术低压管道输水灌溉简称“管灌”,由于投资少、方法简便已被成功地在我国推广应用,在今后相当长的一段时期内仍将在节水灌溉中占主导地位。管道输水是利用管道代替明渠进行输水的一种方法,与渠道输水相比,消除了渗漏损失和蒸发损失,输水过程中水的利用率     

一种农用低压水泥管闸阀的研制

为解决节水灌溉使用低压管道中配套工业用闸阀不合理问题，研制一种与低压水泥沙土管理配套的低压水泥管闸阀，以降低工程投资，促进低压管道输水灌溉发展。     

树状田间管网布置的有关问题探讨

树状田间管网布置的有关问题探讨陈耀锋（山东省东平县州城镇水利站２７１５０６）低压管道输水灌溉技术现已成为平原井灌区的主要灌溉方式，特别是半固定式系统，由于使用管理方便、节水效果明显而迅速发展。管网的布置及管材、管径的选择是否合理，是决定工程投资与效益...     

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

Review of the Egyptian experience in implementing land drainage projects

About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。     

A European irrigation map for spatially distributed agricultural modelling

We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.     

粉质仪和拉伸仪在面粉生产中的应用

在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。