【作者】 翟治芬；

【导师】 赵元忠；

【作者基本信息】 甘肃农业大学 ， 农业水土工程， 2009， 硕士

【摘要】 本研究以武威市气候条件和小区畦灌种植模式为基础,以春玉米金穗1号品种为试验作物,通过设计秸杆覆盖和地膜覆盖两种覆盖方式、四个灌水处理,分析了不同覆盖方式下不同灌溉制度对春玉米土壤温度、土壤含水率、耗水规律、生物学性状、产量以及水分利用效率的影响,求出了春玉米的水分生产函数,并在此基础上,对原有的灌溉制度进行了优化。研究结论如下:(1)地膜覆盖对土壤水分和温度兼有正效应的特点,使春玉米提前出苗,缩短了春玉米的生育期,较秸杆的早15 d,较裸地的早7d。秸秆覆盖在春玉米生长后期具有良好的降温缓冲作用,可延缓其根系衰老过程和延长春玉米的生长期。(2)春玉米的株高和穗位高均随春玉米生长和灌水量的增加而增加。秸杆覆盖下春玉米的株高值较大,地膜覆盖下春玉米穗位高度较大。覆盖条件对春玉米叶面积的影响表现为前期差异大,后期差异小。地膜覆盖下春玉米的地上部干物质最大值出现在抽穗期,而秸杆覆盖下的最大值出现在灌浆期。春玉米植株个体生物量与时间的关系表现为不明显的S型曲线。(3)覆盖方式对产量构成因子的影响差异各不相同,对产量的影响差异显著(P<0.05),各灌水处理对产量及产量构成因子的影响差异均为显著(P<0.05)。地膜覆盖下穗粒数对产量的影响最小,秸杆覆盖下穗长、穗粒数和行粒数对产量的影响因素较小。地膜覆盖比秸杆覆盖更有利于提高春玉米的产量。(4)土壤含水率随灌水量的增加而增加,但灌水对20~80cm土层的土壤含水率影响最大,反映灌水量的差异也最为明显,处理之间0~20cm土层的土壤含水率之间差异不显著,80~120cm土层的土壤含水率则基本保持稳定。(5)春玉米地的棵间蒸发主要受表层土壤水分控制,秸杆和地膜覆盖方式下,棵间蒸发占蒸发蒸腾总量比例随春玉米地上部分及土壤含水量的变化而变化,其总的趋势是大-小-大,秸杆覆盖更有利于减少无效蒸发。在春玉米生长期内,土壤棵间蒸发随叶面积指数变大而变小,在土壤表面湿润的条件下E与LAI的相关性较好。春玉米蒸发蒸腾总量的变化趋势与0~60cm土层土壤含水率变化趋势存在线性相关。(6)春玉米在全生育期内总耗水量随灌溉定额的增大而增大,各处理的耗水强度变化表现为双峰曲线,即在苗期-拔节期和抽穗-灌浆期分别达到两个峰值,同时水分胁迫促使耗水高峰有不同的变化。(7)耗水量和产量之间存在显著的二次抛物线关系。用Jensen模型求解阶段水分生产函数,得到秸杆覆盖下春玉米的需水临界期在抽穗之后,而地膜覆盖在抽穗之前。(8)地膜覆盖条件下春玉米的高效用水灌溉定额为653.19mm,且经济效益也较高。推荐处理f3,为最优灌溉种植模式,即在满足春玉米拔节到抽穗阶段需水量的同时,适当地在拔节之前和蜡熟之后减少灌水。更多还原

【Abstract】 This research was based on the climate condition of WuWei City and district border irrigation planting model, JingSui NO.1 of spring maize was the test crop. By designing straw cover and film mulching, four irrigation treatments, this paper analyzed the different irrigation schedules under different covering ways influenced to soil temperature, soil water content, water consumption, biological characteristics, yield and water use efficiency, and worked out the water production function of spring maize, and the original irrigation schedule has been optimized. The research conclusions were as follows:(1) Film mulching had positive effect to soil content and soil temperature, which made seedling emergence early and shortened the growth stage of spring maize, and comparing to straw cover and bare land, seedling emergence was early 15 days and 7 days respectively. Straw cover had good cooling and bufferaction in lately growth stage of spring maize, which can delay the root senescence and prolong the growth stage.(2) The height of spring maize and spike height were increasing with the growth of spring maize and the irrigation amount. The height of spring maize under straw covering was relatively large, and the spike height under film mulching was relatively high. The effect of covering on the leaf area was great different in the earlier stage of spring maize, and little difference in the later stage. The maximum value of dry matter weights underground by film mulching appeared at the heading stage, and by straw covering was at the filling stage. The relationship between individual biomass and time was an unconspicuous S-type curve.(3) The effect of covering ways on yield component factors were different, and the difference of the effect on yield was significant (P<0.05). The effect of each irrigation treatments on yield and yield component factors were significant(P<0.05). The effect of grain number per spike by film mulching on yield was the minimum. The effect of spike length, grains per spike and kernels per row under straw covering on yield were less. Film mulching more improves the yield than straw covering.(4) The soil water content increased with the increasing of irrigation amount, however, the irrigation water was greatiy effected in the depth of 20~80cm, and the difference of irrigation water was the most obviously. The difference of soil content among different treatments in 0~20cm was no significant, and in 80~120cm was basically keep steady.(5) The soil evaporation was mainly controled by the surface soil water, the proportion of the soil evaporation account to the total evapotranspiration quantity changed with the growth of spring maize and the soil water content, and the trend was big-small-big. Straw covering was more beneficial to reduce ineffective evaporation. In the growth stage, the soil evaporation became small with the increased leaf area index. E and LAI under the surface soil humid condition has good relativity. There was a linear correlation between the change trend of total evapotranspiration quantity of spring maize and the change trend of soil content in depth of 0~60cm .(6) The total water consumption of spring maize in the whole growth stage increased with the increasing of irrigation quota. And the water consumption intensity of each treatment was a bimodal curve, the two peak were from seedling stage to jointing stage and heading stage to filling stage respectively. Meanwhile, water stress impeled the peak of water consumption in different treatments.(7) The relationship between water consumption and yield was a quadratic parabola, through solving stage water production function by using Jensen model, we got that the critical period of water requirement of spring maize bu straw covering was at heading stage, and that by film mulching was before heading stage.(8) The high efficient water use irrigation quota of spring maize by film mulching was 653.19mm, which has a higher economic benefit. The treatment f3 was recommended as the optimal irrigation planting pattern, which meet the water requirement of spring maize from jointing stage to heading stage, meanwhile, can properly reduce irrigation water before jointing and after wax mature.更多还原