宽垄沟灌条件下节水效应试验研究

发布时间：2018-04-26 11:50

本文选题：宽垄沟灌 + 土壤蒸发　；参考：《华北水利水电大学》2017年硕士论文

【摘要】：本文通过试验对宽垄沟灌条件下作物棵间土壤蒸发规律、计划湿润层总体土壤水分动态和不同层深的土壤水分变化规律、灌秸秆覆盖处理对作物耗水规律及产量的影响进行研究,取得的主要成果如下:(1)通过大田试验实测数据,分析了宽垄沟灌和常规畦灌分别在三种不同灌水控制下限的灌溉条件下棵间蒸发的耗水变化规律,对作物每个生育阶段的棵间土壤蒸发量在其阶段耗水量中所占的比例变化情况以及每个处理总的棵间蒸发占总耗水量的比例关系;分别绘制出了棵间土壤蒸发与表层土壤含水率、叶面积指数的关系曲线图,对影响棵间土壤蒸发的两大主要因素进行了系统分析;最后分析了试验田间灌溉后的土壤蒸发强度的变化。结果表明:宽垄沟灌能够明显的减少棵间蒸发,并且效果比较明显,从而可以产生明显的节水效果;相对棵间土壤蒸发与表层土壤含水率、叶面积指数均呈良好的指数函数的关系;灌溉后的前几天,为了达到节水目的,尽量采用少次、多量的灌水方式,并且减少表层土壤湿润面积和时间,在降雨和灌溉后前几天应该采取相应的有效措施拟制棵间土壤蒸发。(2)通过观测不同灌水方式根层土壤水分的动态变化,揭示了不同灌水方式和土层深度土壤含水率的变化规律研究作物的每个生育阶段的耗水规律。结果表明:夏玉米生育期土壤含水量波动较冬小麦频繁,周年内,水分处理越高,土壤含水量波动越大,0~20cm土层内土壤含水率波动频率大,且波动幅度也较大,随着土层加深,土壤含水量波动减小;两种作物都是拔节期到灌浆期耗水量最大,约占全生育期耗水量的45%~50%;与传统畦灌模式相比,沟灌各水分处理的耗水量减少38.15mm~44.13 mm,水分利用效率提高9.17%~22.73%。六个处理中L-70综合表现最优,因为其产量较高、耗水量适度,最主要其水分生产效率最高,两组L-70处理平均分别达到1.84 kg/m3、1.81kg/m3。(3)研究了宽垄沟灌种植下3种水分处理和4种覆盖处理对夏玉米阶段耗水规律及产量的影响。结果表明:同一水分处理下,秸秆覆盖增加了夏玉米的产量,其中F2处理增产效果最显著,增产率可达2.68%~4.58%;出苗—拔节期覆盖处理表现出明显的保墒能力,较F0最高可节水8.32~9.81 mm,拔节—抽雄期和抽雄—灌浆期降雨较多,导致大量的无效水蒸发,F2覆盖处理最适宜;结合水分处理和覆盖处理,L-70水分处理和F2覆盖处理效果最优,产量高达7 815.42 kg/hm2,耗水仅为366.09 mm,水分利用效率为2.13 kg/m3,降水利用效率为5.73 kg/m3。
[Abstract]:In this paper, under the condition of wide ridge furrow irrigation, the law of soil evaporation between crops was studied, and the total soil moisture dynamics and the soil moisture changes of different depths in the wetting layer were planned. The effects of straw mulch treatment on crop water consumption and yield were studied. The main results obtained were as follows: 1. In this paper, the variation of water consumption between trees under three irrigation conditions with three different irrigation control limits was analyzed for wide furrow irrigation and conventional border irrigation, respectively. The variation of the proportion of soil evaporation in the water consumption in each growing stage of crops and the relationship between the total evaporation and the total water consumption of each treatment were studied. The curves of relationship between soil evaporation and surface soil moisture content and leaf area index were plotted, and the two main factors affecting soil evaporation were analyzed systematically. Finally, the change of soil evaporation intensity after irrigation was analyzed. The results show that wide ridge irrigation can obviously reduce interplant evaporation, and the effect is obvious, so it can produce obvious water-saving effect, and the relative soil evaporation and surface soil moisture content, In order to achieve the purpose of saving water, the method of irrigation was adopted as few times and as much as possible, and the surface soil wetting area and time were reduced. Several days before rainfall and irrigation, effective measures should be taken to prepare soil evaporation between trees. (2) dynamic changes of soil moisture in root layer of different irrigation methods should be observed. The variation law of soil moisture content in different irrigation methods and soil depth was revealed. The water consumption in each growing stage of crops was studied. The results showed that the fluctuation of soil water content in summer maize growing period was more frequent than that of winter wheat. The higher the annual water treatment, the greater the fluctuation frequency of soil moisture content in 20cm soil layer, and the larger the fluctuation range was, with the deepening of soil layer. The fluctuation of soil water content was decreased, the water consumption of the two crops was the largest from jointing stage to filling stage, which accounted for 4550% of the water consumption in the whole growth period. Compared with the traditional border irrigation model, the water consumption of each water treatment in furrow irrigation decreased by 38.15mm~44.13 mm, and the water use efficiency increased 9.17% 22.73%. Among the six treatments, L-70 had the best comprehensive performance because of its high yield, moderate water consumption and the highest water production efficiency. The effects of three kinds of water treatment and four mulching treatments on water consumption and yield of summer maize were studied in two groups (average 1.84 kg / m ~ (3) ~ (3) ~ (-1) kg 路m ~ (3) 路m ~ (3) ~ (3). The results showed that straw mulching increased the yield of summer maize under the same water treatment, among which F2 treatment had the most significant effect on increasing yield, the yield increase rate could reach 2.68% 4.58, and the mulching treatment of seedling and jointing stage showed obvious ability to preserve soil moisture. Compared with F0, the highest water-saving rate was 8.32 ~ 9.81 mm, and more rainfall occurred during jointing and heading and filling stage, which resulted in a large amount of ineffective water evaporation and F _ 2 mulching treatment, and the combination of water treatment and mulching treatment had the best effect of water treatment and F _ 2 mulching treatment. The yield was as high as 7 815.42 kg / hm ~ (2), water consumption was only 366.09 mm, water use efficiency was 2.13 kg / m ~ (3) and precipitation utilization efficiency was 5.73 kg / m ~ (3).
【学位授予单位】：华北水利水电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S275.3

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