通过研究全生物降解地膜对马铃薯产量及农田水热特性的影响，寻求旱作区保墒抑蒸及降低农田污染问题的最佳种植措施。以马铃薯品种青薯9号为指示品种，以露地不覆膜为对照，研究了淀粉基降解地膜、纤维素聚合类降解地膜、聚乳酸聚合类(PLA)降解地膜、聚乙烯(PE)地膜等覆盖材料对马铃薯田水热特性和马铃薯产量，以及马铃薯生长期内全生物降解地膜的降解特性的影响。结果表明，不同覆盖处理较露地对照均能显著增加马铃薯全生育期土壤含水率，淀粉基降解地膜、纤维素聚合类降解地膜、聚乳酸聚合类(PLA)降解地膜覆盖处理土壤含水率较聚乙烯(PE)地膜处理分别增加9.23%、24.35%、33.03%，在出苗期和淀粉形成期增幅最大。各覆膜处理在5~15 cm土层处对土壤有显著的增温效应，但各处理增温效果不尽相同。其增温效果由高到低依次为聚乙烯(PE)地膜、聚乳酸聚合类(PLA)降解地膜、纤维素聚合类降解地膜、淀粉基降解地膜。地膜降解性能结果显示，3种生物可降解地膜在10 、20 cm土层的降解率随埋土时间的延续而升高，聚乙烯(PE)地膜处于相对稳定的状态。其中，淀粉基降解膜地面覆盖37 d后达到诱导期，78 d达到完全降解期(无膜期)；纤维素聚合类降解地膜、聚乳酸聚合类(PLA)降解地膜诱导期分别在覆膜后66、79 d开始，分别于121、140 d完全降解。各覆膜处理较露地对照均有增产效果，其中以聚乙烯(PE)地膜覆盖处理增产效果最佳，较露地对照显著增产32.77%；聚乳酸聚合类(PLA)降解地膜覆盖处理、纤维素聚合类降解地膜覆盖处理增产效果较好，较露地对照显著分别增产28.65%、22.69%，较聚乙烯(PE)地膜覆盖处理分别减产3.11%、7.59%；而淀粉基降解地膜覆盖处理增产效果不显著，仅较露地对照增产6.64%，较聚乙烯(PE)地膜覆盖处理减产达19.68%，这可能与其过早降解紧密相关。加之纤维素聚合类降解地膜和聚乳酸聚合类(PLA)降解地膜的降解周期与马铃薯生育期高度匹配，由此可见，聚乳酸聚合类(PLA)降解地膜、纤维素聚合类降解地膜在马铃薯生产上具有推广应用价值。

This study investigated the effects of fully biodegradable mulch film on potato yield and soil hydrothermal characteristics in search of optimal planting methods for conserving soil moisture, suppressing evaporation, and reducing farmland pollution in dry farming areas. Using the potato variety Qingshu 9 as an indicator crop and open-field without mulch as a control, four types of mulch materials, i.e., starch-based biodegradable mulch, cellulose-polymer biodegradable mulch, polylactic acid (PLA)-based biodegradable mulch, and polyethylene(PE) film, were compared for their influence on soil hydrothermal dynamics, potato yield, and film degradationperformanceduring the potato growing season. Results showed that all mulching treatments significantly improved soil water content compared with the control, with increases of 9.23%, 24.35%, and 33.03% under starch-based, cellulose-polymer, and PLA-based mulch materials, respectively, relative to the PE film, and the most significant improvements were observed during seedling emergence and starch accumulation stages. All mulch types exhibited a soil-warming effect at 5 to 15 cm soil depth, with the order of effectiveness being PE film > PLA mulch > cellulose-polymer mulch > starch-based mulch. The degradation performance analysis showed that the degradation rate of the 3 biodegradable films increased with burial duration at 10 and 20 cm soil depths, while PE film remained relatively stable. The starch-based film entered the induction phase 37 days after surface application and reached full degradation at 78 days. The cellulose-polymer and PLA films entered induction at 66 and 79 days, reaching complete degradation at 121 and 140 days, respectively. All mulch treatments enhanced yield compared to the control, with PE film showing the highest increase of 32.77%. PLA and cellulose-polymer films increased yields by 28.65% and 22.69%, respectively, though slightly less than PE. The starch-based film did not significantly improve yield, with only a 6.64% increase over the control and a 19.68% decrease relative to PE, likely due to its premature degradation. Given the alignment of their degradation cycles with the potato growth period, PLA and cellulose-polymer films show promising application potential in potato cultivation.

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国家马铃薯标准化区域服务与推广平台项目(NBFW-17-2019)； 甘肃省科技计划项目(24CXNA011)； 甘肃省农业农村厅科技项目(GNKJ-2021-25)。