城市草坪节水灌溉系统设计

由于经济技术等原因，目前我国草坪灌溉基本上是以地面漫灌为主，这种灌溉方法只能改变土壤湿度，对绿地植物生长的小气候影响小，灌水定额较大，不便实行适时适量灌溉，水的利用率低，加上城市水资源(尤其是北方干旱地区)的日趋紧张，草坪采用节水灌溉势在必行。草坪节水灌溉系统已成为草坪建设中的一个重要组成部分，有必要研究草坪节水灌溉系统设计的科学性。     

基于PDA的草坪节水灌溉决策支持系统

为了将草坪灌溉理论应用于实践指导灌溉,结合专家知识对草坪灌溉研究成果进行了系统集成,设计了基于PDA和移动数据库的草坪节水灌溉决策支持系统.同时,阐述了系统的组成内容以及各功能模块的实现方法.本系统实现了草坪灌溉研究理论向草坪灌溉生产实践的转化,在合理制定草坪灌溉制度,实现节水灌溉方面能够发挥重要作用.     

利用层次分析法优化选择节水灌溉方式

Saaty T L教授创立的层次分析法(AHP)是对非定量事件作定量分析的一种有效方法.为此,对某节水灌溉项目运用层次分析理论和方法来评价节水灌溉方式;针对在节水灌溉评价分析中出现的问题,对层次分析法的应用做出了改进;并利用改进后的层次分析法优化选择出最优节水灌溉方式.     

景电灌区主要作物不同节水灌溉模式效益综合分析

景电灌区是以农业经济为主的高扬程跨流域灌区,干旱缺水成为制约农作物高产稳产的主要因素,节水灌溉技术在景电灌区得到大力推广,合理的节水灌溉方式可以节约用水,提高单方水效益,有利于推进水资源集约节约利用和建设节水型灌区。如何科学合理地选择节水灌溉模式是目前迫切需要研究的问题。基于熵值法,从社会经济效益、生态环境效益等方面构建节水灌溉效益评价体系,对灌区主要作物进行了不同节水灌溉模式的效益分析。结果表明,高效节水灌溉效益普遍高于其他灌溉方式,而滴灌模式则是该地区最优节水灌溉模式。评价结果与实际基本一致,说明这种方法应用到灌区中评价效益是可行的,对灌区的综合评价具有指导意义。     

中国北方城市草坪蒸散特征及影响因素研究 ——以河北张家口市某早熟禾草坪为例

中国北方城市不合理的草坪灌溉以及草坪扩张导致的地表水分大量蒸散,不仅加剧了北方干旱区水资源短缺,也严重制约了水资源可持续发展以及节水城市的建设.以中国北方干旱区河北省张家口市典型早熟禾草坪为研究对象,通过蒸渗仪实测和基于气象和土壤水分要素构建的主成分回归模型,明确了月、日、时不同时间尺度上的草坪蒸散规律及关键影响因子.结果表明:①草坪蒸散呈现"夏季高、冬季低"的季节性特征,最高/最低出现在6/2月份,平均值为5.27/0.29 mm/d;②典型日逐小时草坪蒸散呈现"早晚低、中午高"的单峰型变化,蒸散变化受日照时长和气温影响最大;③10 cm和20 cm深度的土壤水分消耗动态与草坪蒸散变化高度同步;④蒸散与影响因子建立主成分回归模型拟合程度较好,R2=0.70(p<0.01),与蒸散相关性大的影响因素依次为:光合有效辐射>气温>10 cm土壤含水率>空气湿度>风速>20 cm土壤含水率>30 cm土壤含水率.研究结果解析了城市草坪蒸散耗水规律,对城市节水灌溉提供了科学依据.     

石羊河流域主要作物节水灌溉效益评价

石羊河流域是我国典型以农业经济为主的内陆河流域,节水灌溉效益评价是优化节水灌溉模式的基础。对石羊河流域2种粮食作物（制种玉米、春小麦）、2种大田经济作物（酿酒葡萄、苹果）及3种温室经济作物（辣椒、西红柿、黄瓜）进行了不同节水灌溉方的效益评价。评价中考虑经济效益、节水效益以及社会效益,选取净收入、总支出、水分利用率、总灌溉量和市场推广难易程度为评价指标,采用模糊综合评判法,获得了石羊河流域主要作物在不同灌溉方式下的灌溉效益。结果表明,覆膜以及滴灌的方式可以有效提高灌溉效益。     

基于熵权TOPSIS法的灌溉用水效率评价

【目的】对灌区灌溉用水效率进行评价,为灌区节水改造提供科学依据。【方法】通过构建灌溉用水效率综合评价指标体系,基于熵权TOPSIS法对2017—2020年新疆兵团第二师6个灌区的灌溉用水效率进行评价。【结果】熵权TOPSIS法的评价结果与灌区实际情况相符,评价结果排序与灌溉水有效利用系数排序、AHP—模糊综合评价结果排序均具有显著相关性,且熵权TOPSIS法相比AHP—模糊综合评价法的变异系数更大,更有利于灌区灌溉用水效率的等级划分;根据灌区各评价指标等级与灌溉用水效率综合评价等级之间的差异,确定了灌溉用水效率的主控因素。【结论】基于熵权TOPSIS法的灌溉用水效率评价具有可行性,灌区在节水改造建设的同时,应确定合理的灌溉制度,提高灌溉用水效率,建设现代化高效节水灌区。     

安徽省节水灌溉效果评价方法研究

节水灌溉效果评价可评判节水灌溉项目实施的优劣程度,评价指标多,并具有模糊性。针对节水灌溉效果评价的特点,设计了节水灌溉综合评价指标体系,采用专家综合评判与模糊决策理论相结合的方法,建立了节水灌溉效果评价数学模型,并给出了应用实例。     

城市广场草坪智能型非充分渗灌技术

综述城市广场草坪灌溉现状与存在问题,按生态城市建设要求,提出建立城市广场草坪智能型非充分渗灌系统.系统研究利用城市河道水源,通过土壤湿度传感器对土壤湿度持续监测分析和判断,由PLC控制器根据草坪需水要求适时控制灌区电磁阀和低压水泵的开启并完成非充分自动灌溉,也可将土壤积水排出坪地,有效解决城市广场草坪与居民争水,防止灌溉过多过少,减少水分损失,不影响居民锻练活动等方面的问题,同时也提高了草坪管理效率,保证草坪生长与景观.     

喷水带应用初步研究

我国水资源紧缺,使得发展节水灌溉成为总趋势.如今,喷灌、微喷灌、滴灌等先进的节水灌溉技术在我国的应用日渐广泛,从灌溉的技术参数、标准以及相应的设备等各方面的研究和应用都比较成熟.而喷水带的研究尚属空白.随着我国节水灌溉技术的不断推广,蔬菜、草坪、花卉、果树等经济作物的栽培面积不断扩大,实施精细灌溉的广度也越来越大,传统灌溉已经不能适应现代农业的灌溉要求,实施喷水带这种新型的节水灌溉技术是现代农业灌溉的发展方向。     

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。