地面灌灌水频率对土壤水与温度及春玉米生长的影响

针对华北地区降雨分布规律,以北京为典型试验区,在保证作物最优土壤水分下限和灌溉定额相同的条件下,研究了地面灌(水平格田灌)灌水频率对土壤水、热状况及春玉米根系分布和产量的影响.试验结果表明,在春玉米抽雄期以前实施的地面灌各处理中,高频灌溉下土壤平均含水率波动幅度较小,土壤水分能保持在一个比较稳定的范围;灌溉显著延迟气温对地温的影响,具有显著地平抑地温作用,地温受灌水过程、土壤含水率及作物冠层面积的影响较明显.灌水频率对春玉米根长密度在行间和行上的分布存在一定影响,高频灌溉能显著促进春玉米根系在上层土壤中的分布.此外,在人工灌溉和降雨相结合灌溉模式下,地面灌不同灌水频率下春玉米产量差异不显著,北京地区的春玉米地面灌水方法宜采用低频灌.

Effect of surface irrigation frequency on soil water and temperatureas well as growth of spring maize

Field experiment was carried out in Beijing area to study the effect of surface irrigation frequency on soil water, soil temperature and growth of spring maize under the condition of constant irrigation quota and optimal soil water lower limit. The results showed that the variation of average soil water content was small and maintained in a stable range. The surface irrigation obviously delayed the effect of atmospheric temperature on soil temperature and minimized the effect of soil temperature, which was also affected by irrigation process, soil moisture and plant canopy area. The high surface irrigation frequency improved the growth of root system in upper layer soil. Under the condition of joint irrigation of artificial and precipitation the irrigation frequency had a little effect on spring maize yield. It is recommended that low irrigation frequency mode is more suitable for spring maize in Beijing area.