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纤维素保水剂对基质特性和黄瓜幼苗生长的影响 总被引：1，自引：0，他引：1
作为新型高分子节水材料,保水剂能够改善土壤结构,提高土壤储水能力,促进作物生长。比较了微晶纤维素保水剂和秸秆沼渣保水剂在穴盘育苗中对基质理化性质和黄瓜幼苗根系活力、壮苗指数、日均干质量增长量等生长生理指标的影响。试验显示,2种保水剂的施用对改善土壤理化性质和促进黄瓜幼苗生长都具有显著的效果;第36天时,加入保水剂的各处理黄瓜幼苗壮苗指数均高于对照组,施用微晶纤维素保水剂质量分数在0.3%时,黄瓜幼苗日均干质量增长量可达(0.015 4±0.000 9)g/d,壮苗指数达0.489 2±0.076 2,根系活力达61.82μg/(g·h);施用秸秆沼渣保水剂质量分数在0.3%时,黄瓜幼苗日均干质量增长量可达(0.015 6±0.000 4)g/d,壮苗指数达0.508 9±0.098 5,根系活力达60.90μg/(g·h)。研究结果表明,秸秆沼渣保水剂可作为一种新型土壤保水剂应用到黄瓜育苗生产中。 相似文献
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以“大叶香菜”为试验材料,设置T1（草炭∶蛭石∶珍珠岩=3∶1∶1）、T2（草炭∶蛭石∶珍珠岩∶有机肥=6∶1∶1∶2）、T3（草炭∶蛭石∶有机肥=3∶1∶1）、T4（草炭∶蛭石∶珍珠岩∶有机肥=2∶1∶1∶1）、T5（草炭∶蛭石∶珍珠岩∶有机肥=1∶1∶1∶1）和T6（草炭∶蛭石∶有机肥=2∶1∶1）共6种基质配比种植盆栽香菜,研究不同基质配比对盆栽香菜生长及品质的影响。结果表明,T4处理的盆栽香菜茎粗、根长和根体积等生长指标优于其他处理,全株鲜质量相对较大,为2.854 g,全株干质量具有最大值,为0.384 g。T4处理的品质指标可溶性蛋白含量、维生素C含量和叶绿素含量也相对较高,分别为37.78、0.20和2.02 mg/g。因此,建议使用草炭∶蛭石∶珍珠岩∶有机肥=2∶1∶1∶1的基质配比进行盆栽香菜的种植。 相似文献
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沼渣有机栽培基质理化特性及栽培效果试验研究 总被引：5，自引：0，他引：5
以沼渣为主要原料,与蛭石、珍珠岩按不同比例调配成5种复合基质,并对这5种基质的粒径、容重、孔隙度、饱和含水量、EC、pH值、全N、全P、全K等营养元素含量及重金属元素含量理化特性进行了试验分析研究.研究结果表明,复合基质的基本理化指标大多数满足要求,全N、全P的含量十分丰富;基质富含钙,但Mg,Fe,Mn等元素相对缺乏;重金属的测量结果显示,沼渣的Cu含量较高,但经配制的5种复合基质的重金属含量均低于允许标准值以下.栽培试验结果表明:无论从生长发育、产量还是硝酸盐积累看,Ⅱ号基质最适合于辣椒栽培,Ⅰ号基质次之,而单独的沼渣不宜作为栽培基质使用. 相似文献
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应用沼渣替代部分草炭配制育苗基质及应用沼液配制复合营养液,进行茄子穴盘嫁接育苗。介绍该技术的生产设施、用料、砧木与接穗的选择、播种、嫁接、嫁接苗管理及病虫害防治环节的操作要点,为我国北方地区茄子穴盘嫁接苗生产提供技术指导。 相似文献
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无土栽培基质水分特性参数研究 总被引：2，自引：0，他引：2
选用设施无土栽培常用8种基质,试验测定其孔隙度、渗透系数、水分特性曲线、扩散率等水分特性参数,分析得到:基质的水分扩散率与基质含水率之间的关系都符合经验公式D(θ=aebθ,呈指数函数变化,且决定系数较高;基质的导水性用扩散率来表示,得到珍珠岩和蛭石的供水速度快,但不利于保水,降低了灌水效率.综合分析8种基质得到,除珍珠岩、蛭石外,其他6种基质总孔隙度均在70％～ 90％之间,水气比均在2.0～4.0之间,均可作为育苗和栽培基质;采用矩阵法综合评价,得出以国产草炭与珍珠岩质量比2:1,国产草炭、蛭石、珍珠岩质量比3:1:1为基质时最优. 相似文献
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陈静华 《农业机械化与电气化》2004,(4):29-30
机械化育苗是20世纪70年代后国际上发展起来的一种新的育苗方式，目前已成为欧美一些国家专业化商品苗生产的主要方式。所谓机械化育苗，是指用草炭、蛭石、珍珠岩等轻基质为育苗基质，利用专用的育苗机械或设备，采用机械化精量播种一次成苗的现代化育苗技术体 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