春玉米覆膜垄作沟灌条件下土壤水热效应及对产量的影响

Effects of Plastic Mulching Ridge Tillage and Furrow Irrigation on Soil Moisture,Soil Temperature and Yield in Spring Maize Field

为探究河套灌区玉米覆膜垄作沟灌种植模式下土壤温度与含水率的变化规律、两者响应关系及对玉米产量的影响,以灌区玉米常规覆膜宽度(70cm)及当地常见农用宽膜(110cm)进行对比研究。结果表明:土壤温度变化主要受外界因素和含水率的影响,两种覆膜条件下土壤温度具有相同的日变化规律,且深层较表层土壤具有明显的滞后效应;玉米生育前期宽膜具有更好的保温效果,且表层5,10cm处地温变化具有显著或极显著性差异;全生育期内110cm较70cm膜具有明显的保墒效果,5—25cm土壤平均含水率高5.06%,6.83%,3.89%,5.28%和3.44%;各时刻不同土层与温度可以拟合为对数函数,但早晚相关性较差,说明此时段地温变化的机制更为复杂;玉米生育后期5cm处土壤平均含水率与土壤温度呈现反比关系,20cm处呈现正比关系,且低水分条件下土壤温度变幅更大;生育期内玉米生长性状及产量指标也达到显著性水平,且110cm较70cm膜平均产量高14.86%;研究成果可为灌区玉米覆膜垄作沟灌模式下适宜地膜宽度的选择提供科学依据。

This study was conducted to discuss the variation in soil moisture and temperature, the response re- lationship, and maize yield while using plastic mulching ridge tillage and furrow irrigation in Hetao Irrigation District. A comparison study was carried out with respect to the conventional plastic mulching width （70 cm） of maize and local common agricultural wide film （110 cm）. The results show that soil temperatures of two film widths present the same change rule, and temperature in the deep soil has a significant lag effect com- pared with the surface. The wider film has better effect on water-heat preservation at the early stage of maize growth. At the surface, the temperatures changes significantly or extremely significantly in 5 cm deep and 10 cm deep layers. The average moisture content of the 110 cm film in 5-25 cm depths increased by 5.06%, 6.83%,3.89%,5. 28% and 3. 44%, respectively, compared with the 70 cm film over the entire growth stage. The different soil layers and temperatures over time can be described by a logarithmic function, but correlation is poor earlier and later, the mechanism of temperature change is more complicated. The average soil moisture content and soil temperature in 5 cm depth showed an inverse relationship and is directly proportional to the late growth stage of maize in the 20 cm depth, whi/e the soil temperature range is wider under the low moisture content condition. The maize growth characteristics and yield index also reach the significant level, and the yield of the 110 cm wide film increase by 14.86%compared with the 70 cm film. The results can provide a scientific basis for the selection of suitable plastic mulching width under planting practice of ridge tillage and furrow irrigation.