灌溉模式对冬小麦生长发育及水分利用的影响

发布时间：2018-01-23 08:02

本文关键词： 土壤水分动态根系吸水土壤温度根系形态籽粒产量水分利用效率　出处：《中国农业科学院》2016年博士论文　论文类型：学位论文

【摘要】：本文通过2013-2014年和2014-2015年两年的田间试验,研究了华北平原冬小麦对不同灌水方式与灌溉制度的响应。试验为两因子设计,分别为灌溉方式和灌溉制度,即当土壤含水量分别下降到田间持水量的50%、60%及70%时,分别采用喷灌(SI)、地面滴灌(SDI)及地面灌(FI)方式进行灌溉,通过研究不同灌溉方式及灌溉制度对冬小麦地下和地上部生长发育的影响来确定适宜的灌溉方式和灌溉制度。针对这个目标,试验主要关注于土壤水分动态、根系形态发育、根系吸水、土壤温度以及与产量参数相关的作物生理生态和生长发育的变化。最后,基于这些指标的表现对灌溉模式进行评价,确定华北平原冬小麦高效、简便、实用的灌溉方法与灌溉制度。本试验主要研究结论如下:1.利用“Hydrous-1D”模型研究了剖面土壤水分的一维运移规律。灌溉及降水对土壤含水量影响较大,灌溉方式及灌溉制度对0-40cm土层土壤含水率的影响更大,也决定着冬小麦产量以及地上与地下部分与产量有关参数的高低。剖面土壤含水量随着灌溉方式及灌溉制度的不同而发生相应的变化,其通过改变剖面根系吸水(RWU)而成为控制灌溉需水量的关键因子。三月底到四月中旬以及五月的中上旬,每日的根系吸水量可达到6-9 mm/day。可以推测,在这一时间段内如果没有足够降雨的话,则需要对冬小麦进行灌溉。土壤0-20 cm土层为冬小麦主要的水分吸收层,这一土层根长密度(RLD)较高,可提供38-40%的根系吸水量。无论何种灌溉方式,根系吸水量都随着灌溉频率的增加而增大。由于顶层土层根长密度较大,对所有的灌溉制度而言,地面滴灌(SDI)的根系吸水(RWU)要高于喷灌(SI)和地面灌(FI);但在60cm以下的土层中,地面灌模式的根系吸水要高于喷灌和地面滴灌。Es/ET随着灌水总量的增加而减少,SDI的Es/ET值最低,可能是由于此模式下土壤表面湿润面积最小。2、从3月份至收获期连续测定的土壤温度显示,地表土壤温度呈现显著波动,并且地表滴灌的地表温度波动大于喷灌和地面灌,这导致土壤表面频繁变干并产生了水分胁迫,特别是50%田间持水量的处理。通过比较相同灌溉方式的不同灌水下限发现,喷灌50%田持灌水下限处理的地表温度波动幅度比喷灌70%田持灌水下限处理的波动幅度高4.3oC。相似的,通过比较相同灌水下限的不同灌溉方式发现,最大的地表温度波动幅度之差出现在70%灌水下限的地面灌和地表滴灌之间,为3.7oC。比较所有处理发现,最大温度波动幅度之差为5.4oC,出现在地表滴灌灌水下限为50%田持的处理与地面灌灌水下限为70%田持的处理之间。深层土壤温度及其波动幅度随深度逐渐降低,从土壤表面到深层土壤形成了较大的温度梯度。3、通过洗根后扫描,再经过WinRHIZO(2007d)软件分析的方法研究了冬小麦生育期的根系形态变化。所有处理的最大的根系深度和其他根系指标均出现在开花期。表层土壤的根长密度表现为70%灌水下限的地表滴灌在2014年明显高于喷灌,而在2015年明显高于地面灌;但60cm以下土壤的根长密度则以地面灌最高,其次是50%灌水下限的喷灌处理。地表滴灌较低的供水速率几乎使所有灌溉水保持在60cm以上的土层,因此导致根长密度在顶部的高比例分布,并且降低了渗漏量。开花期表层0-10cm土壤的最大根长密度为41.05 cm cm-3,出现在地面滴灌处理中,其次为70%灌水下限的喷灌处理(38.29 cm cm-3)。在90-100cm土层,50%灌水下限的地面灌处理的根长密度最高(3.52 cm cm-3)。在2015年,地面灌的平均根直径大于50%灌水下限的地表滴灌。频繁的灌溉处理显著增加了根生物量、根体积和投影面积。4、为了确定不同灌溉模式的效率,对比分析了冬小麦的产量组成。结果显示,灌溉方式配以适宜的灌溉制度能够显著提高产量组成,并能实现最优产量与灌溉水有效利用间的平衡。产量与需水量结果分析显示,冬小麦产量最高时的灌溉需水量为180.27 mm(加上降雨量约为318.17 mm),即灌水定额为30 mm的SDI或SI需要灌水6次,灌水定额为60 mm的FI则需灌水3次;而当灌水量为154.53 mm时,预计可以获得最高的水分利用效率(WUE)值。这一结果表明,最高WUE可通过灌水定额30 mm的SDI或FI灌水5次或灌水定额60 mm的SI灌水3次实现。对比不同处理间的籽粒产量发现,SDI灌水下限为60%田持处理的产量最高为9.53 t ha-1,SDI灌水下限为70%田持处理的产量次之,为9.37 t ha-1,FI灌水下限为50%田持处理的产量最低,为8.26 t ha-1。SDI灌水下限为60%田持处理的的WUE最高,为2.08 kg m-3,SI同一灌水下限处理的WUE次之,为2.05 kg m-3;SI灌水下限为50%田持处理的灌溉水利用率(IWUE)最高,为9.38 kg m-3,其次为SDI同一灌水下限处理的9.20 kg m-3。结果表明,SDI在增加作物潜在产量和WUE方面表现得更好。为了获得最高产量或最优WUE,适宜的灌溉制度和灌水方法应该保证灌水量在154.53-180.27 mm。这表明在60%田持时对冬小麦进行灌溉是效益最优的灌溉制度,SDI是获取潜在籽粒产量和WUE最佳的灌水方法。本研究推荐即使在干旱年份也要在60%田持时采用SDI进行灌溉,而且建议根据当地天气状况设定灌溉时间。
[Abstract]:In this paper, through field experiments in 2013-2014 and 2014-2015 for two years, studied the response of Winter Wheat in North China Plain of different irrigation methods and irrigation system. The test of two factor design, respectively for irrigation and irrigation system, namely when the soil water content decreased to the water holding amount of 50%, 60% and 70%, respectively irrigation (SI), surface drip irrigation (SDI) and surface irrigation (FI) were affected by irrigation, irrigation methods and irrigation system of underground and aboveground growth of winter wheat to determine suitable irrigation methods and irrigation system. Aiming at this goal, the test focused on the dynamic of soil moisture, root morphology, root water uptake, soil temperature and yield parameters associated with the growth and development of crop physiological and ecological changes. Finally, the performance of these metrics to evaluate the irrigation pattern based on the determination of the North China Plain Winter Wheat Simple and efficient, wheat, irrigation methods and irrigation system. The main conclusions of this experiment are as follows: 1. of one-dimensional migration by using the "Hydrous-1D" model of soil moisture. Irrigation and precipitation on soil moisture influence, irrigation methods and irrigation system has more influence on the 0-40cm soil moisture content, also decided the winter wheat yield and the ground parameters associated with the underground part and the yield. Soil profile water content with different irrigation methods and irrigation system changes, by changing the profile of root water uptake (RWU) has become a key factor for irrigation water requirement. At the end of March to mid April and early May. The amount of daily, root water can reach 6-9 mm/day. that, in this period of time without adequate rainfall, the need for irrigation of winter wheat on soil 0-20 cm. The soil moisture is the main winter wheat absorption layer, the root length density (RLD) can provide high water uptake by roots of 38-40%. No matter what kind of irrigation method, water uptake by roots will increase with the increase of irrigation frequency. Because the top-level root length density of all irrigation, drip irrigation (ground SDI (RWU)) of the root water uptake is higher than that of sprinkler irrigation and surface irrigation (SI) (FI); but below 60cm soil layer, root water surface irrigation mode is higher than that of sprinkler and surface irrigation.Es/ET decreases with the increase of irrigation amount of SDI, the lowest Es/ET value may be due to the mode of soil surface the minimum wetting area.2, soil temperature determination from March to harvest period shows that soil temperature showed significant fluctuations, and the surface temperature fluctuation is larger than the surface drip irrigation sprinkler and surface irrigation, which leads to the soil surface and had frequent dry Water stress, especially the 50% field capacity. Through different irrigation lower limit compared to the same irrigation, irrigation 50% field capacity surface temperature fluctuations processing to fluctuations of irrigation lower limit irrigation lower limit treatment of high 4.3oC. than 70% similar irrigation fields, through different irrigation methods compared with the same irrigation limit that difference the maximum surface temperature fluctuations occur between the 70% irrigation limits of surface irrigation and drip irrigation, found 3.7oC. comparison of all treatment, the maximum temperature fluctuations of the difference of 5.4oC treatment and the ground to appear 50% fields in the surface drip irrigation low limit of irrigation lower limit is 70% of the field capacity between the deep soil temperature. And its fluctuation gradually decreased with depth from the soil surface to deep soil formed by large temperature gradient.3, washing roots after scanning by WinRHIZO (2007d) software. The analysis method to study the changes of root morphology of winter wheat. The maximum root depth all processing and other root index appeared at flowering stage. The root length density of surface soil to surface drip irrigation low limit of 70% in 2014 and in 2015 was significantly higher than that of irrigation, but significantly higher than surface irrigation; root length density the 60cm below the soil surface irrigation was highest, followed by the 50% Irrigation irrigation lower limit. The lower surface drip irrigation water supply rate almost all irrigation water maintained at more than 60cm of the soil, resulting in a high proportion of root length density at the top of the distribution, and reduce the amount of leakage. The maximum surface 0-10cm of soil at flowering stage the root length density of 41.05 cm cm-3, appeared in the surface drip irrigation, sprinkler irrigation treatment followed by 70% irrigation low limit (38.29 cm cm-3). In the 90-100cm soil layer, 50% irrigation limit ground irrigation treatment of the root length density of the most High (3.52 cm cm-3). In 2015, the average root diameter of more than 50% of the surface irrigation irrigation quantity of drip irrigation. Frequent irrigation treatment significantly increased the root biomass, root volume and projection area of.4, in order to determine the efficiency of different irrigation mode, comparative analysis of winter wheat yield components. The results showed that irrigation with the suitable irrigation system can significantly improve the yield components, and can realize the optimal yield and irrigation water utilization balance between water demand and yield. The results of analysis showed that winter wheat yield was the highest when irrigation water requirement is 180.27 mm (plus the rainfall is about 318.17 mm), the irrigation quota of 30 mm SDI or SI need irrigation 6 times, irrigation quota of 60 mm FI to 3 times of irrigation; and when the irrigation amount was 154.53 mm, is expected to get the highest water use efficiency (WUE). The results showed that the highest WUE by 30 mm irrigation quota SDI or FI 5 times of irrigation or irrigation quota of 60 mm SI 3 times of irrigation. Comparison between different treatments of grain yield, SDI irrigation low limit was 60% of field capacity with the highest yield was 9.53 t HA-1, SDI 70% field capacity irrigation limit output processing, 9.37 t HA-1, FI irrigation the lower limit is 50% to the lowest yield field processing, processing to the highest WUE 8.26 t ha-1.SDI irrigation limit of 60% fields, 2.08 kg M-3, SI the same irrigation times WUE treatment, 2.05 kg M-3; SI irrigation low limit was 50% of field capacity with irrigation water use efficiency (IWUE) the highest kg M-3, 9.38, followed by 9.20 kg m-3. SDI the same irrigation treatment showed that SDI in increasing crop yield potential and WUE performance better. In order to obtain the maximum yield and the optimal WUE, irrigation system and irrigation method suitable for irrigation in 154.53-180.27 mm. should ensure that this shows that in the 60% fields Duration of winter wheat irrigation is the best irrigation system, SDI is the best method of obtaining irrigation potential of grain yield and WUE. This study recommended even in dry year but also in the 60% field capacity using SDI irrigation, and suggestions according to the local weather conditions set irrigation time.

【学位授予单位】：中国农业科学院
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S512.11

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