覆膜集雨与限量补灌对土壤水分及冬小麦产量的影响

依据北京昌平2005－2006年冬小麦田间试验，探讨覆膜集雨和限量补灌措施对土壤水分及产量影响。结果表明：限量补灌明显的增加了田间土壤水分和耗水量，1.6 m土层耗水量比对照增加45.8%，比覆膜增加29%～39%，产量是对照的1.63～1.95倍，比单纯覆膜增产32%～58%，结合覆膜比单纯补灌略增加上层土壤水分，但产量效应不明显；在覆膜面积占种植面积40%，降雨是常年水平一半的条件下，覆膜集雨提升上层土壤水分，降低深层土壤水分，1.6 m土层耗水量较对照增加3.68%～12.23%，且对深层水的利用是对照的1.55～1.69倍，小麦抗旱能力增强，增产63%～95%， 1 m土层水分生产效率提高55.8%～73.8%；在都有覆膜的前提下，追肥比早秋施肥和一次基肥更好地保持了苗期土层水分。总体来看，覆膜结合补灌追肥和限量补灌措施抗旱增产效果显著，值得在华北地区旱地农田推广应用。

Effects of field rainwater harvesting by plastic mulch and complement irrigation on soil water and yield of winter wheat

Based on the field experiment conducted in year 2005-2006 at Changping District, Beijing, the effects of field rainwater harvesting by plastic mulch and the complementary irrigation on the soil moisture and yield of winter wheat were studied. Results showed that under the complementary irrigation treatment, soil moisture was improved significantly and water consumption increased by 45.8% in contrast to the control, while by 29%-39% in contrast to the treatment of rainwater harvesting by plastic mulch for the soil profile with depth of 1.6 m. Meanwhile, the yield was 1.63-1.95 times to the control, while increased by 32%-58% in contrast to the treatment of field rainwater harvesting by plastic mulch. In addition, for the treatment of combination with plastic mulch and irrigation, the corresponding yield almost changed nothing. Under the condition of the rainfall closed to the half of normal level and plastic mulch area reached 40% of the total planting area, soil moisture within profile of 1.6 m depth was improved and water consumption increased by 3.68%-12.23%, while, the deep soil water utilization was 1.55-1.69 times to the control, and the yield of winter wheat increase by 63%-95%. The water production efficiency in the soil profile with depth of 1 m increased by 55.8%-73.8%. For the same consideration of plastic mulch, spring top-dressing had the better effect for keeping the soil water content at seeding stage than fall fertilizer and basal fertilizer. In conclusion, both spring top-dressing with plastic mulch during irrigation and complementary irrigation can greatly increase yield, and improve capacity of drought resistance. So it is worth expanding in drought area of North China.