限量补灌对带田冬小麦土壤水分与耗水强度的影响

Effect of limited supplemental irrigation on soil water and its consumption by winter Wheat intercropping with maize

试验结果表明，旱地带田冬小麦不同生育期限量补灌35mm后0～90cm土层土壤含水量在灌水后短期内显著高于来灌水处理，随着生育进程的推进，灌水与未灌水处理的土壤含水量逐渐接近一致；小麦全生育期耗水强度的变化呈"双峰"曲线，虽峰值出现时间不一致，但总是与灌水时间同步变化，各处理基本上以小麦抽穗一扬花期耗水强度为全生育期最高值，且以抽穗期灌水的处理耗水强度最高，日耗水量高达7．68mm／d，认为抽穗期灌水对土壤水分的贡献最大；水分盈亏状况分析表明，带田冬小麦全生育期0～90cm上层土壤水分处于极度亏缺状况，灌水比不灌水处理水分亏缺程度更为严重，但不同生育期灌水的处理间水分亏缺差别极小。

Experimenta results indicated that soil water content in 90 cm depth in arid areaafter 35 mm supplementa irrigaion at different developing stages of intercropping winter wheat was significantly higher than tha of no irrigation treatments within a short period, but with the development of crop growth, all the treatmend gradually tended to be the same in soil water content, The changes of water consuming intensity in wheat developing stages showed 'Double Peak' curves, though the times the peaks appearing was not as the same, they all changed as the same steps as the irrigation times. Throughout all the developing stages the highest water consuming intensity aPpeared between heading and flowering stages with a intensity of 7.68 mm/d, which was the treatment that was irrigated in heading stage, thus heading stage was considered as the best irrigation time in importance of contribution to soil water Waer deficiency analysis had indicated .while harvesting soil water in 90 cm depth was in seriously deficient conditions for intercropping winter wheat, and irrigated treatment was more serious than that of no irrigation, but these deficiencies betWeen treatments that irrigated in different developing stapes hardly showed differences among them.