【作者】 郝芝建；

【导师】 范兴科；

【作者基本信息】 中国科学院研究生院（教育部水土保持与生态环境研究中心） ， 水土保持与荒漠化防治， 2008， 硕士

【摘要】 喷灌作为一种先进的灌水技术,与传统的地面灌溉相比,具有节约用水、增加作物产量、提高作物品质、调节田间小气候、适应性强以及便于自动化控制等优点。基于上述优点,喷灌得以在世界范围内迅速发展和推广。然而,与地面灌溉相比,喷灌过程中存在冠层截留和蒸发飘移损失,导致喷灌水的损失和水量的重新分配。为了了解作物冠层对喷灌水量再分配的影响和水量在地面的分布状况,本文以喷灌夏玉米田间试验为基础,基于水量平衡原理,对喷灌水经玉米冠层后的分配状况和喷灌水在地表的分布规律进行了初步探讨,得出以下结果:1.一次喷灌灌水过程中,由于玉米冠层的影响,喷灌水量在地表的分布既具有同一性,也有差异性。对于同一生育期,同一种植密度条件下的玉米而言,在同一喷灌强度内各测点处的茎秆下流水量和棵间穿透水量都表现出很高的同一性。由于玉米冠层的影响,各部分喷灌水量之间又存在明显的差异性:茎秆下流水量、棵间穿透水量和冠层截留量之间存在明显差异性,棵间水量内部之间也存在明显差异性。2.试验基于水量平衡原理,对喷灌过程中的各部分水量进行了测定,得出了玉米不同生育期的水量分布及冠层截留量。中等种植密度条件下,玉米各生育期茎秆下流水量占冠层上部水量的比例在37.2%～47.0%之间变化,棵间穿透水量的变化范围为43.8%～59.3%。玉米拔节期到灌浆期,冠层截留量分别为0.8mm、1.8mm、2.7mm和2.9mm,到玉米灌浆成熟期,冠层截留量又下降到2.6mm。当行距从60cm增大到70cm时,平均茎秆下流水量占冠层上部水量的比例降低4%,平均棵间穿透水量占冠层上部水量的比例升高5%,最大冠层截留量减小1个百分点。当行距不变,株距由30cm减为25cm时,平均茎秆下流水量占冠层上部水量的比例增加2%,平均棵间穿透水量占冠层上部水量的比例减小3%,最大冠层截留量增大1个百分点。3.正常种植密度条件下,玉米灌浆期有43.8%的灌水量经玉米茎秆下流到根区,47%的灌水量以棵间穿透水量的形式非均匀分布于玉米周围地表。在玉米茎秆周围不同距离、不同方位处,棵间穿透水量的分布也不相同。在距离玉米茎秆7cm,15cm,25cm和32.5cm处,地表接收的水量占总灌水量的比例分别为18.9%、43.5%、66.9%和84.5%。在叶方位向,行向和垂直叶方位向三个方位,棵间穿透水量占灌水量的比例分别为49.8%、17.4%和68.5%。单株玉米植株周围地表处的喷灌均匀系数和分布均匀系数的均值分别为32.9%和24.3%,喷灌有效均匀系数接近40%,喷灌水在地表分布的均匀性较差。更多还原

【Abstract】 As a advanced irrigation technique, sprinkler irrigation water has several advantages than traditional ground irrigation such as saving water, enhance crop production, improve crop quality, adjust microclimate, strong adaptability and convenient for automation control. Sprinkler irrigation has been developed and spread in the worldwide for these advantages. However, compared with surface irrigation, the water was intercepted by canopy, evaporation and excursion and causes the water loss and distribution during sprinkler irrigation. In order to find out the effect of maize canopy on sprinkler irrigation distribution and water condition of land surface, the paper discussed the distribution regulation of crop canopy and sprinkler water in the land surface on the basis of water balance principle. The results as below:1. Because of the influence of maize canopy, the sprinkler water distribution in land surface has its identity and difference during an independent irrigation. On the one hand, the stemflow and throughfall water shows high identity under the same growth stage, same plant density and same sprinkler irrigation intensity. On the other hand, the water distribution shows strong difference both in different parts water and in throughfall penetrate water for the influence of corn canopy.2. According to the water balance principle, water in different parts was measured, and summer maize water distribution and canopy interception during the growing stages were made out. In the moderate plant density, the maize stemflow accounted for 37.2%～47.0% of water applied above canopy, and the throughfall is 43.8%～59.3%. The canopy interception water is 0.8mm、1.8mm、2.7mm and 2.9mm from maize jointing stage to maize filling stage. The canopy interception water decreases to 2.6mm in the maize filling and ripening stage. While the row spacing decrease from 60 cm to 70 cm, the average stemflow decrease 4% account for water applied above canopy, and the average throughfall increase 5% account for water applied above canopy; the maximal canopy interception water decrease 1%. While the row spacing not change and the plant spacing decrease from 30 cm to 25 cm, the average stem flow increase 2% account for water applied above canopy; the average throughfall decrease 3% account for water applied above canopy; the maximal canopy interception water increase 1%.3. In the normal planting intensity, 43.8% water irrigated passed through stem and flowed to root zone during maize filling stage; and 47% water as throughfall distribute around the ground surface unevenly. The throghfall water distribution is different in different distance to maize stem and different orientation. The water supplied to land surface accounted for 18.9%、43.5%、66.9%和84.5% of total irrigation water in the distance of 7 cm,15 cm,25 cm and 32.5 cm to maize stem. The throughfall water account for 49.8%, 17.4% and 68.5% of total irrigation water in the leaf orientation,row orientation and vertical row orientation. The sprinkler irrigation uniformity coefficient and distribution uniformity coefficients is 32.9% and 24.3%; and the sprinkler irrigation effective uniformity coefficient is close to 40% in the land surface around each maize plant. Sprinkler water distribution uniformity in land surface is poor.更多还原