摘要:为探究地下滴灌条件下不同灌溉量与滴灌带间距对夏玉米生长发育与耗水特征的影响, 查明地下滴灌对田间尺度水平衡的影响特征, 基于2种灌溉定额(62 mm和35 mm)与3种滴灌带间距(60 cm、80 cm和100 cm)的田间试验, 并以华北典型农田地面灌溉方式为对照, 分析不同处理对夏玉米生长发育、土壤剖面水分分布、蒸散量及土壤蒸发的影响。结果表明: 地下滴灌处理灌溉水主要停留于20~60 cm土层, 灌溉量越高, 湿润范围越大; 相对地面灌溉处理, 地下滴灌处理地表0~20 cm与60~100 cm土壤含水量相对较低。玉米株高、叶面积指数与干物质积累量随地下滴灌灌溉量的增加而增加, 地面灌溉处理可促进株高与干物质积累, 地下滴灌低灌溉量导致玉米生育进程延迟。与地面灌溉处理相比, 地下滴灌处理可在减少22%的灌溉量的条件下保证作物产量无显著下降, 土壤蒸发相对降低30%, 蒸散量相对降低8%, E/ET值由0.34降低至0.27, 灌溉水利用效率提高20%, 收获指数增加10%。不同滴灌带间距处理对玉米生长发育及耗水特征无显著影响。综合夏玉米生长、产量、灌溉水利用效率和滴灌设备投资成本, 本试验条件下最优设计方案为灌溉量为62 mm, 滴灌带间距为100 cm。
关键词:夏玉米/
地下滴灌/
土壤蒸发/
土壤水分/
水分利用效率
Abstract:Water and soil resources in the North China Plain are mismatched. Traditional flood irrigation methods in this area have low water resource utilization and lead to serious water loss, which has caused a rapid decrease in groundwater levels. This study aims to improve the efficiency of irrigation water use in this area, determine the influence of subsurface drip irrigation on the field-scale water balance, and explore the effects of different irrigation amounts and drip irrigation zone spacing on the growth and water consumption of summer maize under subsurface drip irrigation conditions. Field experiments with two irrigation quotas (62 and 35 mm) and three drip irrigation pipes spacings (60, 80, and 100 cm) were conducted with the conventional flood irrigation as the control in farmlands in the North China Plain to analyze their effects on the growth and development, yield and irrigation water use efficiency of summer maize, and the soil profile moisture distribution, evapotranspiration, evaporation. Soil evaporation under subsurface drip irrigation was measured and compared using a microlysimeter. The results showed that irrigation water from subsurface drip irrigation mainly stayed in the 20–60 cm soil layer, and the wetted body presented a “small up and large down” form. The higher the irrigation amount, the larger the wetted body range, and the larger the soil volumetric water content. Compared to flood irrigation, the soil moisture contents of the 0–20 cm and 60–100 cm soil layers from subsurface drip irrigation were relatively low, and a dry soil layer formed at about 0–10 cm layer, which reduced soil evaporation. Maize plant height, leaf area index, and dry matter accumulation increased with increasing amounts of subsurface drip irrigation. Under flood irrigation, the maize plant height increased faster, and the accumulation rate of the maximum dry matter was higher compared to subsurface drip irrigation. Low amounts of subsurface drip irrigation delayed maize growth. When the irrigation amount was reduced by 22%, maize yield under subsurface drip irrigation did not differ from maize yield under traditional flood irrigation. Compared to flood irrigation, subsurface drip irrigation reduced soil evaporation by 30%, evapotranspiration by 8%, the E/ET value from 0.34 to 0.27; and increased the irrigation water use efficiency by 20%, the harvest index by 10%. The different drip irrigation zone spacing treatments had no effect on the growth and water consumption of maize. For high maize growth and yield, efficient irrigation water use, and cost-effective investments in drip irrigation equipment, the optimal irrigation quota was 62 mm with a drip irrigation zone spacing of 100 cm.
Key words:Summer maize/
Subsurface drip irrigation/
Soil evaporation/
Soil moisture/
Water use efficiency
PDF全文下载地址:
http://www.ecoagri.ac.cn/article/exportPdf?id=b0d1c20f-4537-4f0f-b467-966efa1d57f7
