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1.
陈志明 《安徽农业科学》2012,40(3):1750-1752
中药材种植基地的喷灌系统,要求既满足灌溉需要又不影响中药材收获对象的产量和质量。结合中药材喷灌工程实例,阐述了管道布置、喷头选择、喷头间距和支管间距的确定、主管与支管的管径计算、管道水头损失计算、喷灌强度计算、水泵选配等喷灌设计方法以及开挖管道沟、安装管道和立杆、安装水泵和控制系统、安装喷头等施工过程和注意事项,全部设计安装过程为大面积生产基地的基础农业设施建设提供了参考。  相似文献   

2.
不同节水灌溉技术下水分运动的试验与模拟   总被引:1,自引:4,他引:1  
根据灌溉水分运动规律,建立了水分入渗和土壤蓄水量动态模型。对喷灌、滴灌、渗灌及波涌灌几种方式下,小麦和玉米两种作物的水分入渗和土壤蓄水量动态进行了对比试验和模拟研究,分析了不同灌溉方式的灌溉机理。  相似文献   

3.
In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain(NCP). The combined effects of water and nitrogen application uniformity on the grain yield, water use efficiency(WUE) and nitrogen use efficiency(NUE) have become a research hotspot. In this study, a two-year field experiment was conducted during the winter wheat growing season in 2016–2018 to evaluate the water application uniformity of a center pivot with two low pressure sprinklers(the R3000 sprinklers were installed in the first span, the corresponding treatment was RS; the D3000 sprinklers were installed in the second span, the corresponding treatment was DS) and a P85 A impact sprinkler as the end gun(the corresponding treatment was EG), and to analyze its effects on grain yield, WUE and NUE. The results showed that the water application uniformity coefficients of R3000, D3000 and P85 A along the radial direction of the pivot(CU_H) were 87.5, 79.5 and 65%, respectively. While the uniformity coefficients along the traveling direction of the pivot(CU_C) were all higher than 85%. The effects of water application uniformity of the R3000 and D3000 sprinklers on grain yield were not significant(P0.05); however, the average grain yield of EG was significantly lower(P0.05) than those of RS and DS, by 9.4 and 11.1% during two growing seasons, respectively. The coefficients of variation(CV) of the grain yield had a negative correlation with the uniformity coefficient. The CV of WUE was more strongly affected by the water application uniformity, compared with the WUE value, among the three treatments. The NUE of RS was higher than those of DS and EG by about 6.1 and 4.8%, respectively, but there were no significant differences in NUE among the three treatments during the two growing seasons. Although the CU_H of the D3000 sprinklers was lower than that of the R3000, it had only limited effects on the grain yield, WUE and NUE. However, the cost of D3000 sprinklers is lower than that of R3000 sprinklers. Therefore, the D3000 sprinklers are recommended for winter wheat irrigation and fertigation in the NCP.  相似文献   

4.
The objective of this research was to assess the effect of soil cracks on soil moisture distribution under various sprinkler irrigation applications and to identify the optimal irrigation strategy that enhances soil moisture distribution and reduces water drainage for the upper soil layer 0–250 mm. The assessment was made for six irrigation events: the first two were for 10 and 46 mm water applications using a hand shift-set sprinkler system. The second set was for 43 and 19 mm water applications using the lateral move system with fixed sprayer heads and the third pair of events were for 43 and 32 mm water applications using the lateral move system with rotating sprinklers. The experiments were conducted on two adjacent fields at the University of Queensland, Gatton, Australia. Each field was divided into 2 m × 2 m grids that covered 62 sampling locations. For each event, the initial soil moisture content (SMC) was measured at each sampling location before irrigation. After irrigation, catch can readings were recorded for each sampling location. After 12 h overnight, the second set of soil moisture measurements was taken at each location. The area1 distribution of SMC for the studied applications was quantified. An attempt was made to identify the relationship between the applied water uniformity using catch cans and the soil moisture uniformity using gravimetric water content measurements. The study also took into consideration variables that could affect the soil physical and hydrological properties including the field slope, the soil texture, the infiltration rate, the salt content and the soil organic matter content of the two fields. Since the soils were cracking clay Vertisols, further analyses were conducted on the crack dynamics, size and distribution using image analysis techniques. The research findings demonstrated that the cracks were the main contributors to water drainage below 250 mm soil depth due to the micro-run off from the crust surface to the cracks. The cracks ranged from a few millimeters to more than 40 mm in width. It was observed that the cracks which were wider than 15 mm remained open after irrigation for the specified application rates. Improving the irrigation system application uniformity did not always result in higher uniformity of the surface SMC (0–250 mm). The event that best enhanced soil moisture distribution and thus improved soil moisture recharging was observed after the sixth irrigation event when the field received 32 mm water application. The soil was at a relatively high initial SMC of 25%, (which represented 43.3% of the plant available water range) and the sprinkler water uniformity was rather high above 87% Christiansen coefficient of uniformity (CUc). At this SMC, the extent of soil cracking is limited.  相似文献   

5.
喷灌技术在我国农业灌溉领域应用较广。目前常规使用的固定式喷头、旋转式喷头和孔管式喷头由于不能实现高低压的自动转换,无法同时兼顾远近射程的不同需求。而脉冲式喷头虽可对灌溉区域进行间断均匀地调节,但费用偏高,广大农民消费不起。笔者从节能的视角出发,设计出一种能实现高低压自动转换的喷头装置,且价格低廉、操作简便,在我国农村地区具有较大的推广空间。  相似文献   

6.
To adapt to the trend toward low-energy precision irrigation, the droplet distributions for two new prototype sprinklers, outside signal sprinkler(OS) and fluidic sprinkler(FS), were compared with impact sprinkler(IS). A laser precipitation monitor was used to measure the droplet distributions. Droplet size and velocity distributions were tested under four operating pressures for nozzles 1.5 m above the ground. For the operating pressures tested, the mean OS, FS and IS droplet diameters ranged from 0 to 3.4, 0 to 3.5, 0 to 4.0 mm, respectively.The mean OS and FS droplet velocities ranged from 0 to6.3 m$s–1, whereas IS ranged from 0 to 6.3 m$s–1. Being gas-liquid fluidic sprinklers, droplet distributions of the OS and FS were similar, although not identical. IS mostly produced a 0.5 mm larger droplet diameter and a 0.5 m$s–1greater velocity than OS and FS. A new empirical equation is proposed for determination of droplet size for OS and FS, which is sufficiently accurate and simple to use. Basic statistics for droplet size and velocity were performed on data obtained by the photographic methods. The mean droplet diameter(arithmetic, volumetric and median)decreased and the mean velocity increased in operating pressure for the three types of sprinkler.  相似文献   

7.
It has been established that under conditions of the Astrakhan oblast, on brown semidesert soils with sprinkler irrigation, an irrigation intensity of 1.2 mm/min and irrigation dose of 250—300 m(su3)/ha should not be exceeded. If irrigation exceeds this dose it is necessary to take measures to increase the infiltration capacity of the soil and reduce the volume of surface runoff.  相似文献   

8.
积极推广和采用节水灌溉技术是实现西部干旱半干旱地区农业可持续发展的有效途径。利用甘肃省张掖市甘州区农户的实地调查资料,采用Probit模型,分析同质性关系与异质性关系的技术采用效应,探讨同质性关系与异质性关系影响农户技术采用的内在机理。结果表明,有80.9%的农户已采用节水灌溉技术,19.1%的农户尚未采用;在采用节水灌溉技术中,有67.8%的农户选择使用低压管灌,21.1%的农户采用滴灌技术,喷灌、微灌、渗灌技术的采用率相对较少。社会网络对农户节水灌溉技术采用具有显著正向影响,但同质性关系与异质性关系对技术采用的影响存在差异,与同质性关系相比,异质性关系对农户节水灌溉技术采用的影响更为显著;户主年龄、家庭规模、非农就业比率、合作社参与情况、政府推广等显著影响农户节水灌溉技术采用。研究表明,加强与异质人群的交往有助于提高农户节水灌溉技术采用率。因此,提出了培育与建立农户异质关系网络;积极发展农村专业合作组织;加大对农技推广工作的政策支持和资金投入等建议。  相似文献   

9.
自进式旋转喷头是管道清洗用高压水射流清洗装置的关键执行部件,为了保证自进式旋转喷头在管道清洗过程中能够稳定地自进和旋转,分析了自进式旋转喷头的喷嘴数目、夹角及偏心量对其运动和清洗效果的影响,通过对比旋转式喷头与非旋转式喷头、无偏心喷头的喷嘴布置及清洗效果,得出结论:喷嘴数目、夹角及偏心量是保证喷头自进和旋转的关键,且三者之间相互关联,进而分析了喷嘴布置设计的要点。基于此,提出了一种合理高效旋转喷头的喷嘴布置方式,既能使自进式旋转喷头稳定运动,又能提高高压水清洗的效率。  相似文献   

10.
[目的]为了研究节水灌溉方式对玉米产量及构成的影响。[方法]2012年在武威荒漠生态与农业气象试验站设计了滴灌、喷灌、漫灌大田试验,并调查玉米整个生育期内的作物生长高度、叶面积指数、株子粒重等指标。[结果]滴灌条件下生物量高于喷灌和漫灌,拔节时差异最明显,滴灌比喷灌重48%、比漫灌重109%;滴灌叶面积指数最高,喷灌次之;在成熟期,滴灌、喷灌株高均较漫灌高22em;滴灌和喷灌百粒重分别重于漫灌11.88%、9.95%;滴灌、喷灌株子粒重分别重于漫灌24.8%、21.1%;滴灌理论产量大于喷灌22.59%,大于漫灌35.62%,喷灌大于漫灌10.63%;滴灌实际产量大于喷灌1.68%,大于漫灌6.52%,喷灌大于漫灌4.76%。[结论]3种灌溉技术条件下,滴灌效果最好,喷灌次之。  相似文献   

11.
安金龙  李玉花  马振平  杨凡  齐树亭 《安徽农业科学》2014,(33):11975-11977,11985
以圆形喷灌机为模型,通过数学计算并结合ANSYS仿真软件,对168径圆形喷灌系统的喷头进行研究.在喷头等间距的情况下,研究了在给定进口压力下,达到均匀灌溉时各喷孔等效半径的大小;研究了在给定等效喷孔大小的条件下,随着进口压力变化喷灌均匀度的变化;研究了在改变第一喷孔大小时,达到均匀灌溉桁架上剩余等效喷孔大小的变化趋势.  相似文献   

12.
针对已有方形喷洒域喷头存在喷灌均匀系数低、方形程度差、转动过程精度不高等问题,设计了一种适用于方形喷洒的新型喷灌装置.该装置主要由控制模块、工作模块和喷头组成;通过滚子与空间凸轮的接触,调节喷头仰角,改变射程,实现方形区域的喷洒;采用单片机控制装置的旋转速度,以提高喷灌均匀度.在工作压力0.20 MPa、流量1.30 ...  相似文献   

13.
生态流量控制与水库其他效益之间的矛盾是河流生态流量保障实践运行的最大障碍,协调生态保障与水库既得利益间的平衡关系是开展面向河流健康的水库调度的重要前提。本研究以河流生态需水过程为生态控制目标,结合文峪河梯级水库的运行需求,划定不同阶段的多目标寻优秩序,并据此建立梯级水库多目标调度模型。依据不同水平年来水状况及远景年的相应措施,设置不同调度情景进行梯级水库模拟调度,得到不同情景下的梯级水库调度方案。最后,对方案中梯级水库的供水保证率、发电量、生态保证率等指标进行统计对比,分析无、低限、适宜三个生态流量控制下的文峪河梯级水库综合效益统计指标的变化规律。研究结果显示:(1) 三个生态流量约束限制,对下游的城镇与工业用水影响不大,其保证率高达99.39%。(2) 对灌溉用水而言,由于将生态流量优先权设置在灌溉用水前,对农田灌溉用水的影响是客观存在的,农田灌溉用水的保证率随生态流量的增加,有所降低,适宜生态流量控制方案较不考虑生态约束方案,保证率下降了10%,且很多枯水年份,破坏的月份达到了8个月,即一年中大部分月份不能满足灌溉需求,可见其破坏程度以及其潜在的经济社会影响不容小视。(3) 三个方案下泄的生态水量都较多,且水量过程差别不大,但生态水量下泄多发生在灌溉用水满足的时段。(4) 由于城镇工业用水、农业用水以及生态用水都是从下游取水,其变化对发电量的影响较小。且实施最小生态控制情况下,梯级水库的强制下泄水量有所减少,为柏叶口和文峪河水库间的补偿调节,提供了更多的空间。通过联合运用,在保障下泄水量要求的情况下,柏叶口相对增发,使梯级总发电量增大,并略高于其他两种方案。  相似文献   

14.
ZY-2型喷头水力性能及喷头组合试验   总被引:1,自引:0,他引:1  
在农大试区,对ZY-2型喷头组成的半固定式喷灌系统进行了实喷测试。结果表明:在喷头工作压力为298m,喷水量为279m3/h的条件下,组合喷灌强度为0167mm/min,距喷头165m处(最大喷水区)的打击强度为28mm,组合均匀性系数为0858,均符合喷灌技术要求,效果良好。为进一步研究喷灌强度及打击强度对不同作物种类、不同生长期的影响提供理论和实践依据,为研究喷头的组合形式和移动轨迹作先期准备工作。  相似文献   

15.
新型条带喷灌机设计思路及总体设计研究   总被引:1,自引:1,他引:0  
针对原有圆形喷灌系统受风影响大、喷洒不均匀、成本高和使用不方便且一直得不到推广的问题,进行了条带喷灌机总体构思思路和设计思路的深入研究,并且进行了总体设计。新型条带喷灌机总体思路是利用农户现有的机械,如农用车动力、喷农药柱塞泵和输水软管,设计一套采用叶轮条带旋洒的新型喷头,沿着植物行间实施田间隔行喷洒的、可移动的新型条带喷灌机。它造价低、使用方便、性能可靠,容易在缺水山区和丘陵区等广大干旱半干旱地区的小农户中推广使用,为新农村建设提供一项重要的技术支持。  相似文献   

16.
To better interpret summer maize stomatal conductance(g_s) variation under conditions of changing water status at different growth stages,three water stress indicators,soil water content(SWC),leaf-air temperature difference(AT) and leaf level water stress index(CWSI_L) were employed in Jarvis model,which were J_s,J_T and J_c models respectively.Measurements of g_s were conducted in a summer maize field experiment during the year 2012-2013.In the insufficient irrigation experiment,three levels of irrigation amount were applied at four different growth stages of summer maize.We constructed three scenarios to evaluate the performance of the three water stress indicators for estimating maize g_s in a modified Jarvis model.Results showed that J_T and J_c models had better simulation accuracy than the J_s model,especially at the late growth stage(Scenario 1) or considering the plant recovery compensation effects(Scenario 2).Scenario 3 indicated that the more environmental factors were adopted,the better prediction performance would be for J_s model.While for J_T model,two environmental factors(photosynthesis active radiation(PAR),and vapor pressure deficit(VPD)) seemed good enough to obtain a reliable simulation.When there were insufficient environmental data,CWSI_L would be the best option.This study can be useful to understand the response of plant stomatal to changing water conditions and will further facilitate the application of the Jarvis model in various environments.  相似文献   

17.
随着时代的不断进步,我国对于灌区管理工作的开展有新要求。灌区管理人员是连接政府与农民的直接主体,其服务质量和方式直接关系到相关政策的实施和灌区运营管理体系的构建。本文以新公共服务理论为出发点,就新疆农田水利管理工作所面临的困境进行探讨和分析,提出新公共服务体系视角下的灌区管理新模式,以期进一步提高灌区管理水平。  相似文献   

18.
Uniformity testing of variable-rate center pivot irrigation control systems   总被引:3,自引:1,他引:3  
As water supplies become limited, agricultural water use needs to become more efficient to maintain current productivity levels. The efficiency of center pivot and linear move irrigation systems can be increased by matching the amount and rate of water application to specific soil conditions that vary in the field. Such site-specific application can be achieved by variable-rate control systems. Although such systems are being developed, their effects on center pivot and linear move uniformity have not been documented. The uniformity along the length of a center pivot and a linear move irrigation system was measured at two system movement speeds and three variable-rate settings. One variable-rate system is commercially available using pneumatically actuated solenoid valves to turn groups of sprinklers ON and OFF at fractions of a minute corresponding to the cycle rate, for example a 50% cycle rate is 30 s ON and 30 s OFF. The other variable-rate system used commonly available electric solenoid valves to accomplish the same task. Overall, the coefficient of uniformity and low quarter distribution uniformity averaged 93% and 0.90, respectively for the center pivot irrigation system; 84% and 0.74 for the linear move system. The results were not significantly (P > 0.05) affected by wind speed, cycling rate, or system movement speed. The type of nozzle did influence the uniformity because of the distinctly different application characteristics of rotator, fixed plate, and wobbling low pressure sprinklers. Thus, the variable-rate technologies tested under the conditions presented in this paper had at least as good uniformity as the center pivot and linear move systems when functioning in non-variable-rate mode.Mention of a trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the University of Florida or the University of Georgia and does not imply approval of a product or exclusion of others that may be suitable.  相似文献   

19.
为了寻找马铃薯适宜的水肥管理模式,通过大田试验,以大水漫灌+肥料条施为对照(CK),研究了喷灌+肥料条施、滴灌+肥料条施和滴灌水肥一体化对马铃薯土壤酶活性及产量的影响。结果表明,与CK相比,滴灌水肥一体化、滴灌+肥料条施、喷灌+肥料条施处理均不同程度地提高了马铃薯土壤酶活性,其影响程度为滴灌水肥一体化滴灌+肥料条施喷灌+肥料条施,滴灌水肥一体化能够显著提高马铃薯生育后期的土壤酶活性。滴灌水肥一体化处理下马铃薯的产量和商品薯率最高,显著高于其他处理,其中,产量较CK及喷灌+肥料条施、滴灌+肥料条施处理分别提高49.07%及27.94%、14.91%,商品薯率较CK及喷灌+肥料条施、滴灌+肥料条施处理分别提高19.41个百分点及10.36、4.72个百分点。  相似文献   

20.
不同灌溉方式对香蕉产量和品质的影响   总被引:4,自引:0,他引:4  
采用大田试验方法,研究了滴灌、漫灌、微喷灌3种灌溉方式对香蕉产量及品质的影响。结果表明,香蕉产量以微喷灌处理最高,分别比漫灌和滴灌处理增产2.3%和4.3%;漫灌处理的香蕉总糖、维生素C含量均显著高于滴灌和微喷灌处理,微喷灌处理的维生素C含量显著高于滴灌处理;可食率以微喷灌处理最高,漫灌处理最低,3种灌溉方式之间差异均显著;干物质含量以微喷灌处理最高,滴灌处理最低,二者间差异显著。在香蕉约100d的生长期内,微喷灌处理的用水量比漫灌少约19%。综合来看,在3种灌溉方式中,微喷灌是在最适宜于香蕉的方式。  相似文献   

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