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为了研究龙眼的需水规律及其微喷灌的增产效益，选择“福眼”和“东璧”2个龙眼品种，应用微灌技术，做微灌与不补水的单因素对比试验。试验设置树冠微喷灌、树下微喷灌、涌泉灌、对照4种处理，分别测量了喷灌水量、需水、需水强度有果实产量、质量、并对各处理的试验结果进行了分析。树冠微喷灌与树下微喷灌效果基本一致，可根据龙眼果园的地貌等条件选择不同的喷灌方法，涌泉灌处理灌水效益不明显。 相似文献
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针对谷物联合收获机产量监测系统成本高、结构复杂和稳定性较低的问题,设计了基于占空比测量的谷物联合收获机产量监测系统,由对射式光电传感器、GPS模块、数据处理单元、数据存储单元和可视化单元组成。系统工作时,通过对射式光电传感器监测刮板上谷物遮挡与不遮挡两种电压信号,通过软件系统处理信号中高度对应的占空比,利用占空比与产量计量模型的关系获得产量数据,并连同系统的绝对时间、GPS数据存储到系统中。通过EDEM仿真和理论模型分析,推导了占空比测量值与谷物质量的正比例关系。利用台架试验对占空比测量值与谷物质量进行了全局模型和局部模型拟合,决定系数R2均不小于0.988。随后通过台架试验对全局模型和局部模型进行模型分析,台架试验结果表明,虽然局部模型可能对固定转速下的测量数据更优,但全局模型更具有通用性。随着系统测量数据的增加,相对误差逐步减小。田间试验中对系统测量的异常信号进行了统计和分析,为了减少异常信号对测产误差的影响,对系统测量值与实际产量进行了标定。田间试验结果表明,产量监测系统测产最大相对误差为3.83%,平均相对误差为0.40%,系统整体误差和误差波动均较小。 相似文献
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叶尔羌河灌区棉花灌溉试验 总被引：2，自引：0，他引：2
棉花试验设计了五个灌水下限处理，每个处理四个重复，试验提供了各种处理的１ｍ土层储水量动态过程，进行了田间土壤水平衡，分析了棉花生长耗水强度与灌水量关系，棉花产量与灌水量关系，棉花产量及水分生产率与全生育期总耗水量关系。 相似文献
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为探明膜下滴灌玉米产量和不同灌水定额的关系,基于大田试验,对玉米全生育期内测量了株高、基部茎围,记录了灌水情况及产量等指标。试验结果表明:膜下滴灌玉米总体株高、基部茎围、产量随着灌水定额的增加而呈上升趋势,玉米基部茎围在生育后期有下降趋势。处理W5下玉米株高、基部茎围最大,当灌水定额在W5以上不利于玉米生长。因为,一方面处理W6的产量最大,W5和W6对产量无明显差异,另一方面,W5的灌溉水利用系数比W6高且在6个处理中最高,所以当灌水定额大于W5时,单方面增加灌水定额以提高玉米产量的做法是不可取的。经相关性分析,单株有效穗数、灌溉水利用系数对玉米产量呈显著性相关。综合分析后处理W5中是最好的选择。 相似文献
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为研究有机肥对连作茄子产量和品质的影响，以施化肥为对照，设置猪粪肥、鸡粪肥和羊粪肥处理，研究茄子品质和产量的变化特征。结果表明，施用有机肥均能够在不同程度上影响茄子品质和产量，在各取样日期，猪粪处理下茄子可溶性糖含量最高。6月20日和7月10日，鸡粪处理维生素C和游离氨基酸含量最高，硝酸盐含量最低。7月30日，猪粪处理维生素C和游离氨基酸含量最高，硝酸盐最低。鸡粪处理产量最高，发病指数和发病率最低。鸡粪有机肥不仅能提高茄子产量而且可明显降低黄萎病发病率，是一种高产高效的施肥方式，在茄子生产上具有较好的应用前景。 相似文献
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小孔的图像处理与圆度误差的评定 总被引：5，自引：0，他引：5
小孔的测量，特别是对其圆度误差的测量与评定，一直是小孔测量中一项较难解决的课题。为此本文提出了对小妃的测量采用图像处理方法进行数据采集，二值化处理，去噪声和边缘检测，进而对圆度误差进行评定，试验表明，这种方案提供了检测和评定小孔圆度误差的可靠方法，并且它具有新颖性，先进性和实用性。 相似文献
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Overland water and salt flows in a set of rice paddies 总被引：1，自引：0，他引：1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
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. 相似文献
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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。 相似文献
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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。 相似文献
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对《种子法》存在问题的探讨 总被引：1，自引：0，他引：1
李鹏 《农业机械化与电气化》2011,(6):129-130
《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。 相似文献
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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. 相似文献
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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。 相似文献
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Gunter Wriedt Marijn van der Velde Alberto Aloe Fayçal Bouraoui 《Agricultural Water Management》2009,96(5):771-789
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. 相似文献
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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。 相似文献
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车辆ABS控制算法的研究及探讨 总被引：1，自引：0，他引：1
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。 相似文献