西北地区微灌标准体系的意义和作用

微灌技术是当今诸多节水技术中节水效率最高的技术。旨在通过对国内、国外微灌节水技术发展现状和发展趋势的调研了解,在系统地分析研究国内外全部微灌标准后,构建一个层次分明、结构合理、内容完整、技术先进的微灌节水标准体系框架。规范微灌产品质量标准,制定一系列技术标准,提高微灌技术的标准化水平。     

微灌标准体系研究概述

微灌是当今诸多节水技术中节水效率最高的一种灌溉技术,构建微灌技术标准体系,制定相关微灌技术标准,是规范农用节水灌溉器材市场,推广微灌技术的有效途径。通过对国内、国外微灌技术、微灌标准发展现状及发展趋势的调研了解,提出了微灌标准体系主要研究内容及技术路线。从微灌技术实施流程出发,参照水利标准体系,构建结构合理、内容完整的微灌标准体系框架和标准明细表。在此基础上制修订30多项地方标准,起草2项国家标准,并进行了微灌条件下作物-水-肥-土壤关系模型研究探索。提高了微灌技术标准的完整性和可操作性。提出了制修订国家、行业微灌技术标准的具体建议。     

我国微灌技术和设备现状及市场前景分析

简要地回顾我国微灌技术发展历史 ,总结我国微灌技术和设备材料研究与推广应用成果以及发展趋势。通过分析我国微灌设备材料技术性能、规格品种和适应性 ,指出我国微灌设备材料整体技术水平不高 ,适应力不足。同时对我国微灌发展前景进行了预测和分析     

微灌技术初探

微灌技术节水效果明显,是我国节水灌溉重点推广技术。阐述微灌技术的概念和分类,介绍微灌技术的国内外应用情况,比较滴灌、微喷灌、涌流灌3种微灌技术的优缺点和适用范围,分析微灌技术的发展空间。     

微灌技术初探

微灌技术节水效果明显,是我国节水灌溉重点推广技术。阐述微灌技术的概念和分类,介绍微灌技术的国内外应用情况,比较滴灌、微喷灌、涌流灌3种微灌技术的优缺点和适用范围,分析微灌技术的发展空间。     

微灌机械化节水技术研究

微灌机械化技术的应用对于缓解我国农业用水紧缺、促进节水型农业发展具有重要意义。介绍微灌技术的概念和常见的微灌形式,简述微灌系统组成,阐述该技术的优点,以期为微灌机械化技术在现代化农业生产中的推广应用提供参考。     

微灌的国际标准

1978年末,国际标准化组织委员会为制定灌溉设备和灌溉系统的国际标准,成立了第23技术委员会的第18分委员会。从那时起,制定了有关灌溉与微灌部件(如喷水器、滴头、滴管、聚乙烯灌溉管道、管件、过滤器、压力调节器及各种型式的闸阀)的建议草案和其它文件。这篇文章介绍了有关微灌国际标准化的活动情况及他们在确保灌溉设备质量方面的重要性,并提出对今后工作的设想。     

编后

我国微灌经历了18年的科研、试点和推广应用。微灌设备的研制工作取得了长足的进步,令人鼓舞。为了展示、交流我国近几年来微灌设备研制新成果及经验,1991年7月9日至12日,在西安召开了《全国微灌设备新进展研讨会》。会上收到论文和技术资料40余篇。为了进一步促进微灌技术的进步和发展,尤其是为了使微灌设备研制出现一个更新的局面,中     

喷微灌技术发展的影响因素分析

本文分析了世界喷、微灌技术发展概况和趋势，总结了典型国家（美国、以色列、印度）的喷、微灌技术发展状况和成功经验，分析了可量化因素和不可量化因素对喷、微灌技术发展的影响，结果表明喷、微灌技术的发展可以明显地降低灌溉用水比例；推进喷、微灌技术发展的主要因素为：人均水资源占有量、人均GNP、农业劳动力人口比例、政府重视程度、投资补贴、研究与培训。     

微灌加气技术研究进展

微灌加气技术是通过微灌管网加气来改善根区土壤通气条件进而保障作物正常生理活动的,它体现着微灌技术集成性的发展趋势,目前微灌加气技术已有较深入研究。首先从微灌加气对作物的影响、对土体环境的影响、微灌加气方式与设备3个方面总结归纳了微灌加气技术现有的研究成果。总体认为:加气可提高作物产量、品质,促进植株生长;能使土壤根区环境发生变化,改善土壤理化特性,提高酶活性;文丘里、空气压缩机等加气设备均可用于微灌加气技术,但不同的加气设备及其加气运行模式可产生不同效果。在此基础上,指出了今后微灌加气技术的发展方向,建议深入开展微灌加气试验,探讨不同地域微灌加气的推广适用性;研发加气设备,保障性能稳定;同时结合理论分析和模型模拟等手段,加强微灌下水肥气热各因子间交互作用机理研究。文章可为微灌加气技术的发展提供一定的技术支撑。     

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.     

车用发动机润滑油失效规律与更换周期研究

研究在正常使用条件下１０Ｗ／３０－ＱＣ级润滑油用于某型车用发动机时所表现的失效规律,确认期服从两参数Ｗｅｉｂｕｌｌ分布,并给出分布的尺度参数η和形状参数ｍ之最佳线性无偏估计（ＢＬＵＥ）同时,还为定量分析,计算车用发动机润滑油的使用可靠性和合理确定其更换周期提供了一套可供借鉴的方法,并给出了具体的计算实例。     

农村剩余劳动力就业问题的探讨

论述了我国农村剩余劳动力就业的意义，并针对我国农村剩余劳动力的现状，提出多渠道促进农村剩余劳动力就业的途径和办法。     

乡（镇）农业技术推广体系存在的问题及对策

乡（镇）农技推广体系是农业发展的关键。介绍朝阳市农业技术推广体系的现状,针对目前体制及运行机制、服务手段等方面存在的问题,提出适合朝阳市乡（镇）农技推广体系改革与发展的对策,以期对全省农技推广体系改革和发展起到一些借鉴作用。     

草莓的采收与贮藏

草莓果味酸甜爽口,营养价值高,为人们所喜爱的应市鲜果之一。由于草莓易受损伤和微生物侵染,因此其采收、贮藏过程极为重要。介绍草莓采收过程中的注意事项以及11种贮藏保鲜技术的实施步骤和操作方法,推介9种加工方式,为草莓产业化提供技术支持。     

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。