共查询到20条相似文献，搜索用时 31 毫秒
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以Blank作物模型为基础,采用动态规划方法确定甜菜优化灌溉制度,以期达到节水高产的目的。就内蒙古河套灌区永联试区的实际情况,计算结果表明,除苗期、完熟期不需灌溉外,其余5个生育阶段均需灌溉,灌水量分别为50m~3/亩,全生育期灌溉定额为250m~3/亩,实际根产量为3902.2kg/亩。 相似文献
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干旱少雨、水资源短缺,是甘肃河西农业可持续发展的瓶颈.根据甘肃省委、省政府的战略部署,要求把节约水资源、提高水资源利用率作为关系河西灌区可持续发展的战略任务,通过农业高效节水,为工业化、城镇化和产业化腾出用水空间,为实现河西灌区的可持续发展创造条件,甘肃省政府制定了三年内发展节水耕作面积66.67万hm2的规划.河西灌区是甘肃省的粮仓,是我国优质啤酒大麦主产区之一,啤酒大麦常年播种面积8万～12万hm2.但河西灌区水资源利用率较低,单方水粮食生产率为0.8 kg左右,比全国平均水平低0.2 kg左右.为了加快甘肃省河西灌区农田节水技术推广步伐,推进节水型社会建设,提高水资源的利用效率,促进灌区农业可持续发展,实现农业增效和农民增收,探索研究各种农田节水措施有其 相似文献
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《Plant Production Science》2013,16(5):592-600
AbstractThis research was conducted to determine the yield and water-use efficiency of maize under fixed and variable alternate furrow irrigation (fixed AFI, variable AFI) and every furrow irrigation (EFI) at different irrigation intervals in areas with shallow and deep groundwater. In variable AFI, water was applied to the furrow, which was dry in the previous irrigation cycle. The results indicated that even at 4-day irrigation intervals the water needs of maize on a fine textured soil in both areas (with deep and shallow water table) are not met by AFI. The decrease in grain yield due to water stress was mainly due to the decrease in the number of grains per cob and to a lesser extent to the decrease in 1000-grain weight. At the Kooshkak site with shallow groundwater (between 1.31 and 1.67 m), grain yields in AFI at 4- and 7-day intervals were comparable to those obtained in EFI at 7- and 10-day intervals, respectively. This might be due to the contribution of groundwater to the water use of the plant (about 5-10%). In the Badjgah area, with deep water depth, grain yield in AFI at 7-day intervals was statistically lower than that obtained in EFI at 10-day interval. In AFI, a shorter irrigation interval (4-day) may alleviate the water stress and result in no yield reduction compared with that in EFI at 7-day intervals even though water application was reduced. Furthermore, in the area with a shallow water table, AFI at 7-day intervals may be superior to EFI at 10-day irrigation intervals. When seasonal irrigation water is less than 700 mm, it may be preferable to use AFI at 10-day intervals to increase water-use efficiency, especially in areas with shallow groundwater. In general, when water was insufficient for full irrigation, the relative grain yield (yield per unit water applied) of maize under AFI was higher than those under EFI. 相似文献
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滴灌与漫灌对小麦生长的影响及经济效益比较 总被引：1，自引：0，他引：1
根据新疆小麦生长特性,分析滴灌与漫灌2种不同灌溉方式对小麦生长的影响,并对2种灌溉方式下小麦的经济效益进行了比较。结果表明:滴灌小麦节水、节肥和增产效果明显,滴灌技术在新疆小麦种植上具有明显优势。 相似文献
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为探讨宁夏引黄灌区滴灌玉米光合响应机制,采用Li-6400XT气体交换测量系统测定2年玉米大喇叭口期的光响应曲线,选取4种通用的光响应曲线模型分别对玉米光响应过程进行分析、拟合与比较,筛选出6个不同氮素处理下最优光响应模型,并利用最优模型计算分析玉米光合生理特征参数。结果表明,滴灌玉米功能叶片光合能力随着施氮量的增加呈递增趋势。通过模型误差计算与分析,4种光响应曲线模型拟合精度存在差异,且直角双曲线、非直角双曲线和指数模型对于高氮处理的光响应曲线拟合度均高于低氮处理。相对其他3种模型,直角双曲线修正模型拟合精度最高,可作为最优光响应曲线模型模拟引黄灌区水肥一体化玉米光响应动态。由最优模型对各氮素处理光响应生理参数计算分析表明,360 kg/hm^2氮处理玉米叶片的光响应参数均高于其他氮处理,有利于提高玉米对强光的适应范围和光能利用效率,增强光合作用。 相似文献
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《Journal of Crop Improvement》2013,27(2):299-315
Summary The production of sunflower grains for roasting was investigated in two soil types under different quantities of applied saline and non-saline irrigation water, different irrigation managements, soil salinity due to previous use of saline water or due to a raised water table. It was shown in one experiment, conducted in a loess type soil, that sunflowers extracted water at least to a soil depth of 120 cm, when the available water from the top layers was used up. The crop in this soil consumed all the available soil water from nearly the entire root zone, while in the clay soil limited water was consumed from deep layers, due to the high salinity and lack of aeration. No decrease in yield was found in the loess soil when 75% of the full amount of water (which was 0.8 of Class A pan evaporation rate) was applied. When only 50% was applied a significant decrease in yield was obtained. In contrast, in the clay soil even 75% of the full amount of water decreased the yield remarkably. Under dry-land conditions approximately 65% of maximum yield was found in the loess soil but only 45% in the clay soil. These differences are all attributed to a shallow active root system in the clay soil. Residual soil salinity from previously use of saline water had no effect on grain production in the loess soil, while saline irrigation water applied during the irrigation season decreased production, but only when water supply was not rate limiting. The combination of saline water and residual soil salinity had a marked effect on the decrease of grain yield under limited irrigation. In both soils a reduction in the amount of water applied per single irrigation and maintaining the entire irrigation period caused a significantly smaller decrease in yield than shortening the irrigation period and applying the full demand. 相似文献
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以2006年～2009年连续4a试验资料为依据,对水稻节水灌溉方式、产量和节水量进行分析探讨。研究表明,利用水稻不同生育期根层土壤水分含量确定灌水时间和灌水量,能够在增产的前提下节约用水174.8m3/667m2。 相似文献
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为了探讨灌水和非灌水条件下冬小麦对水分的利用特点,在大田条件下研究了灌水与非灌水两种处理对冬小麦的耗水结构、土壤水分利用程度及水分与产量之间的关系。结果表明,在非灌溉条件下,冬小麦主要利用20~60 cm土层中的水分,冬小麦对土壤贮水的消耗量增加,平均多耗水96.84 mm;土壤水分利用程度提高,较灌水区提高26.8个百分点;耗水系数增加,水分利用效率增大;冬小麦的产量与0~100 cm土层的含水量有密切的关系,这些土层内的含水量变动对产量的影响最大。 相似文献