水保所知识产出(1956---)知识库

 为缓解内蒙古河套灌区水资源短缺并实现农业节水，在河套灌区开展连续两年(2016 年和 2017 年)的田间
试验，采用膜下滴灌种植春玉米，设置5 个基于土壤水基质势的灌水下限水平，分别为 －10 kPa(S1)、－20 kPa(S2)、
－30 kPa(S3)、－40 kPa(S4)、－50 kPa(S5)，研究不同灌溉处理下的土壤水分分布与春玉米生长及耗水特性。研
究结果表明，2 个生长季内不同基质势水平下土壤含水率差异明显，基质势越高，土壤剖面平均体积含水率越高;不
同土壤水基质势下限控制的灌水水平显著影响玉米生长，随着生育期内土壤水基质势控制下限的降低，玉米株高
与叶面积指数显著降低(p ＜0. 05)，其中 S5 处理玉米发生早衰现象;地上部干物质积累量、百粒质量、穗粒数等产
量构成指标都随土壤水基质势下限的升高而增加;土壤水基质势水平越高，玉米产量越高，其中 S1、S2 和 S3 处理
玉米产量显著高于 S4 和 S5，但是前三者之间不存在显著差异(p ＜0. 05);随着土壤水基质势的降低，水分利用效率
先增大后减小，－30 kPa 时水分利用效率最高。综合考虑作物产量和水分利用效率，建议将河套灌区玉米膜下滴
灌土壤水基质势下限控制在 －30 kPa 为宜。

 The Hetao Irrigation District in the Inner Mongolia is one of the most important bases for
commodity grains in China． However，there was a substantial reduction in the total water quantity
diverted from the Yellow Ｒiver． In order to alleviate the crisis of water shortage and promote agricultural
water-saving in the irrigation district，a two-year field experiment was conducted，in which five different
threshold values of soil matric potentials (SMP) were set to trigger the mulched drip irrigation for spring
maize，i． e． ，－10 kPa (S1)，－20 kPa (S2)，－30 kPa (S3)，－40 kPa (S4) and －50 kPa (S5)．
The soil water distribution，crop growth，and water use efficiency (WUE) were studied for the different
treatments． The results showed that soil water contents varied significantly at different SMP threshold
values during the two growing seasons of spring maize． The weighted averages of volumetric water content
in the 0 ～ 60 cm soil profile were increased significantly with the increase of SMP (p ＜ 0. 05)． Whenunder lower SMP threshold values，plant height and leaf area index (LAI) of maize were relatively lower
during the growing season． And premature senility of maize was observed when under the SMP threshold
value of － 50 kPa． Aboveground biomass，hundred-grain weight and number of grains per spike were
increased with the increase of SMP threshold values． When under higher SMP threshold values，higher
maize yields were obtained． The yields of treatments of S1，S2 and S3 were significantly higher than those
of S4 and S5 (p ＜ 0. 05)，but there were no significant difference among S1，S2 and S3． With the
decrease of SMP threshold value，WUE was increased first and then decreased． The highest WUE value
was obtained when under the SMP threshold value of －30 kPa． Therefore，both taking into account the
yield and WUE，it was recommended that the SMP value of －30 kPa can be the threshold value to trigger
mulched drip irrigation for spring maize production in the Hetao Irrigation District．