不同覆盖方式对小麦产量和土壤水热状况的影响

目的]研究不同覆盖方式对土壤水热变化特征及春小麦产量的影响,为该地区选择蓄水保墒的覆盖材料及方法提供理论依据。方法]试验以传统无覆盖平作为对照(CK),设置秸秆覆盖量SW1(1 500kg/hm2),SW2(3 000kg/hm2),SW3(4 500kg/hm2),全膜覆土穴播(FT),全膜垄作(RT),共6个处理。结果]与CK相比,RT能提早小麦出苗时间,缩短生育期时间(103d),而SW3推迟小麦出苗,延缓了生殖生长(生育期124d);小麦苗期FT,RT处理对0—5cm土层增温效果显著,以RT处理增温显著,较CK增温3.97℃,拔节至成熟期FT,RT处理增温效果逐渐减弱,SW1,SW2及SW3处理在小麦苗期对0—5cm土层具有降温作用,拔节至成熟期表现为增温效应,SW3增温效果最好;小麦苗期FT,RT处理0—100cm土层土壤水分含量显著高于CK,SW1,SW2及SW3处理,小麦拔节至成熟期SW1,SW2及SW3处理0—100cm土层土壤含水分量高于其他处理,以SW3处理最高;FT,SW3处理增产效果最佳(FT,SW3SW2SW1RTCK),比CK增产46.23%,且SW3可以显著降低小麦生育期耗水量(18.53%),改善水分利用效率(67.67%)。结论]秸秆覆盖SW3(4 500kg/hm2)可以改善土壤水热状况,减少小麦耗水量,增加水分利用效率,提高小麦产量,与全膜覆土穴播可能造成的白色污染相比,适宜在旱作小麦生产中应用和推广。

Effects of Different Mulching Patterns on Soil Hydrothermal Characteristics and Wheat Yield

Objective] The influences of different field mulching treatments on soil hydrothermal characteristics and grain yield of spring wheat were studied to provide theoretical basis for the selection of mulching materials and method of soil moisture conservation.Methods] The experiment had six treatments:traditional flat planting (CK),three levels of wheat straw(straw mulching quantities were 1 500 kg/hm2 (SW1),3 000 kg/hm2 (SW2),and 4 500 kg/hm2 (SW3)),whole field soil-plastic mulching (FT),and ridges were covered with plastic and the furrows received no mulching (RT).Results] As compared with CK,RT could advance the seedling emergence,and shorten the growth duration days (103 d).Whereas,SW3 could delay the emergence,postpone the growth duration (124 d).Treatments of FT and RT could increase soil temperature (0-5 cm) and soil water content (0-100 cm) at the seedling stage.The averaged soil temperature increment was 3.97 ℃ under RT in comparison with that of CK.Treatments of FT and RT could not increase soil temperature (0-5 cm) and soil water content (0-100 cm) remarkably at stages from jointing to maturity.SW1,SW2 and SW3 decreased soil temperature (0-5 cm) and soil water content (0-100 cm) at the seedling stage,whereas increased soil temperature (0-5 cm) and soil water content (0-100 cm) at stages from jointing to maturity.Soil water content was higher under SW3 treatment than those of others.Wheat yields under FT and SW3 treatments were significantly higher than those of other treatments (SW3,FT＞SW2 ＞ SW1 ＞RT＞CK).In comparison with the yield of CK,the significant increase under SW3 was 46.23 ％,water use efficiency increased by 67.67％,and total water consumption decreased by 18.53％.Conclusion] Soil moisture and temperature conditions were both improved,wheat yield and water use efficiency were also increased,simultaneously total water consumption was decreased.If the problem of "white pollution" of plastic film mulching is considered,undoubtedly,the wheat straw mulching SW3 (4 500 kg/hm2) is appropriate for its environment-friendship,high-yielding management solution and ecosystem sustainability in dryland agriculture.