不同颜色地膜和种植密度对春玉米田间地温、耗水及产量的影响

【目的】 探求不同颜色地膜和种植密度对东北雨养区春玉米田间地温、耗水量、产量和降水利用效率的影响,进一步挖掘旱作雨养玉米水分生产潜力。【方法】 2016—2018年开展了3种覆盖处理（裸地、透明地膜覆盖和黑色地膜覆盖）和3种种植密度（60 000、75 000和90 000株/hm ²）的栽培试验,定位监测0—25 cm土壤耕层温度和0—120 cm土壤水分动态变化,结合作物产量分析农田水分利用效率。【结果】 在生育前期,透明地膜覆盖处理土壤耕层积温显著高于黑色地膜覆盖处理,黑色地膜覆盖处理土壤耕层积温显著高于裸地处理;种植密度的增加使得玉米拔节期以后的土壤耕层积温下降;从全生育期耗水量看,黑色地膜和透明地膜覆盖处理间无显著差异,但均显著低于裸地处理;无论在平水年还是枯水年,玉米耗水量均随种植密度的增加而增加;黑色地膜覆盖玉米产量和水分利用效率显著提高,平均较透明地膜分别高4.3%和4.6%,较裸地分别高9.2%和13.3%;在相同覆盖处理下,产量和水分利用效率随着种植密度的增加而增加;在高密度处理下,地膜覆盖明显提高经济效益,黑色地膜覆盖平均比透明地膜覆盖获得的利润多807.82元/hm ²。【结论】 黑色地膜覆盖结合高密度（90 000株/hm ²）栽培模式,在保证玉米高产的基础上,水分利用效率达到最高,本研究可为东北雨养旱作玉米进一步挖掘降水生产潜力及增产增效提供参考。

Effects of Different Colored Plastic Film Mulching and Planting Density on Soil Temperature,Evapotranspiration and Yield of Spring Maize

【Objective】 Field experiments were conducted to explore the effects of different colored plastic film mulching and planting density on the topsoil temperature, evapotranspiration, grain yield of spring maize and precipitation utilization efficiency in the rain-fed area of Northeast China, in order to further tap the water production potential of dryland and rain-fed maize. 【Method】 Complete combination field, including three types of mulching ( non-mulching, transparent plastic film mulching and black plastic film mulching ) and three planting densities ( 60 000, 75 000 and 90 000 plants/hm ²) , were conducted to monitor the topsoil temperature dynamics in 0-25 cm depths and the soil moisture dynamics in 0-120 cm depths, and to analyze the water use efficiency combined with grain yield of maize in 2016-2018.【Result】 The results showed that the accumulated temperature of the plough layer in the transparent mulching film treatment was significantly higher than that in the black mulching film, and the accumulated temperature of the plough layer in the black mulching film treatment was significantly higher than that in the non-mulching treatment in the early growth stages of maize. The increase of planting density reduced the accumulated temperature of the plough layer after jointing stage of maize. For the evapotranspiration of the growing season, there was no significant difference between the black plastic film mulching treatment and the transparent plastic film mulching treatment, but they were significantly lower than the non-mulching treatment. The evapotranspiration increased with the increasing of the planting density whether in the normal precipitation year or the dry year. Maize grain yields and water use efficiency were significantly improved in the black plastic film mulching treatment, with an average of 4.3% and 4.6% higher than that of the transparent plastic film mulching treatment, respectively, and 9.2% and 13.3% higher than that of the non-mulching treatment, respectively. Yield and water use efficiency increased in tandem with planting density under the same mulching treatment. The plastic film mulching significantly improved the economic benefits under high-density treatment, and the profit of the black plastic film mulching was 807.82 yuan/hm ² more than that of the transparent plastic film mulching.【Conclusion】 The cultivation mode of black plastic film mulching and high density (90 000 plants/hm ²) combined treatment could improve the utilization rate of natural precipitation and achieve the highest water use efficiency on the basis of ensuring high grain yields. This paper provided a scientific and effective way to further tap the water and crop production potential in the dryland and rain-fed regions of China