研究黄土旱塬不同厚度生物降解地膜对作物产量和水分利用效率的影响，为黄土旱塬区生物降解地膜应用提供参考依据。采用0.006、0.008、0.010 mm 3种厚度的生物降解地膜，以裸地为对照，测定不同处理土壤水分、植株性状、产量和水分利用效率等指标。结果表明，生物降解地膜厚度减薄会显著降低地膜对水分的保蓄能力，覆膜后150 d，0.006 mm生物降解地膜单株叶面积小于裸地，0.008、0.010 mm生物降解地膜单株叶面积较裸地分别增加20.2%、22.2%。覆膜后120 d，0.006、0.008 mm生物降解地膜叶片SPAD值与裸地没有明显差异，0.010 mm生物降解地膜叶片SPAD值较裸地增加4.2%。生物降解地膜厚度对春玉米产量和水分利用效率有显著影响，生物降解地膜越厚，春玉米产量和水分利用效率越高，但0.008、0.010 mm生物降解地膜在产量和水分利用效率上没有显著差异。

To investigate the effects of biodegradable mulching films with different thickness on crop yield and water use efficiency(WUE), and to provide reference for the application of biodegradable mulching film in the Loess Plateau. Soil moisture, plant traits, yield and water use efficiency were measured with three different thicknesses of biodegradable plastic film(0.006 mm, 0.008 mm and 0.010 mm) used and bare ground as the control. The results showed that the thinning of biodegradable plastic film could significantly reduce the water retention capacity of plastic film. After 150 days of mulching, the leaf area per plant of 0.006 mm biodegradable mulching film was less than that of bare ground, the leaf area per plant of 0.008 mm and 0.010 mm biodegradable mulching film was 20.2% and 22.2% higher than that of bareground, respectively. When mulching with plastic film for 120 days, the SPAD values of leavesin 0.006 mm and 0.008 mm biodegradable plastic film mulching were not significantly different from that of bare ground, and the SPAD value of leaves in 0.010 mm biodegradable plastic film mulching was increased by 4.2% compared with the control. The thickness of biodegradable mulch had a significant effect on maize yield and water use efficiency. The thicker the biodegradable mulch, the higher the maize yield and water use efficiency, but there was no significant difference between 0.008 mm and 0.010 mm biodegradable mulch in yield and water use efficiency.

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国家重点研发计划(2021YFD1900700、2016YFB0302402、2021YFD1100500)；甘肃省重大专项(21ZD4NA022)；国家现代农业产业技术体系(CARS-02-55)；甘肃省农业科学院重点研发计划项目(2022GAAS38)。