Yang Chong, Zhao Yang, Long Bibo, Wang Feiyan, Li Fayong, Xie Dong
Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou 510316, China.
Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou 510316, China.
Ecotoxicol Environ Saf. 2023 Oct 1;264:115402. doi: 10.1016/j.ecoenv.2023.115402. Epub 2023 Aug 26.
Biodegradable mulch films are recognized as a promising substitute of polyethylene (PE) films to alleviate the "white pollution". Biodegradable mulch films with optimum degradation rates increase crop yield even compared to PE films. However, the mechanisms underlying this yield-increasing effect remains elusive. In this study, three biodegradable film treatments (BFM1, BFM2 and BFM3) and one PE film treatment (PFM) were used to evaluate their effects on soil and winter potatoes, and a partial least squares path model (PLS-PM) was constructed to investigate their relationships. The degradation rates of films under different treatments were ranked as BFM3 > BFM2 >BFM1 > PFM, and presented distinctive effects on soil properties and nutrients, structure of soil bacterial community, and yield traits of winter potatoes. The PLS-PM showed that mulch treatments affected potato yield through effects on soil properties (soil water and temperature) and soil nutrients (TOC, DOC, TN and NO-N). The disintegration of the biodegradable films decreased soil water content and temperature, and reduced the loss of soil nutrients in the topsoil at the later growth stage of winter potatoes compared to PE films. Additionally, the elevated content of soil TN and NO-N under treatment BFM1 may play a key role in its yield-increasing effect on potatoes compared to treatments PFM and BFM2. Thus, biodegradable mulch films with proper degradation rates regulate soil TN and NO-N through their effects on soil water and temperature, and subsequently improve the yield of winter potatoes compared to PE mulch films.
可生物降解地膜被认为是缓解“白色污染”的聚乙烯（PE）薄膜的一种有前途的替代品。与PE薄膜相比，具有最佳降解率的可生物降解地膜甚至能提高作物产量。然而，这种增产效应背后的机制仍然难以捉摸。在本研究中，采用三种可生物降解薄膜处理（BFM1、BFM2和BFM3）和一种PE薄膜处理（PFM）来评估它们对土壤和冬马铃薯的影响，并构建偏最小二乘路径模型（PLS-PM）来研究它们之间的关系。不同处理下薄膜的降解率排序为BFM3 > BFM2 > BFM1 > PFM，并且对土壤性质和养分、土壤细菌群落结构以及冬马铃薯的产量性状呈现出不同的影响。PLS-PM表明，地膜处理通过对土壤性质（土壤水分和温度）和土壤养分（TOC、DOC、TN和NO-N）的影响来影响马铃薯产量。与PE薄膜相比，可生物降解薄膜的分解降低了土壤含水量和温度，并减少了冬马铃薯生长后期表土中土壤养分的流失。此外，与处理PFM和BFM2相比，处理BFM1下土壤TN和NO-N含量的升高可能在其对马铃薯的增产效应中起关键作用。因此，与PE地膜相比，具有适当降解率的可生物降解地膜通过对土壤水分和温度的影响来调节土壤TN和NO-N，进而提高冬马铃薯的产量。
