Aiming to address the problem of soil environmental pollution caused by the large-scale use of plastic film in agricultural production in China, field experiments were carried out by applying degradable plastic film. Pumpkin was used as the research material to explore the effects of black common plastic film (CK), white degradation plastic film (WDF), black degradation plastic film (BDF), and black CO2-based degradable plastic film (C-DF) on soil physicochemical properties, root growth and yield, and soil quality. The results showed that the soil water content and temperature of the three degradable plastic films were lower than those of ordinary plastic films to different degrees; there was no significant difference in soil organic matter content among the treatments. The soil available potassium content of the C-DF treatment was lower than that of CK, and WDF and BDF had no significant effect. Compared with those in CK and WDF, soil total nitrogen and available nitrogen contents in the BDF and C-DF treatments were lower, and the difference between treatments reached a significant level. Compared with that of CK, the catalase activities of the three types of degradation membranes were significantly increased by 2.9%-6.8%, and the sucrase was significantly decreased by 33.3%-38.4%. Compared with that in CK, the soil cellulase activity in the BDF treatment was significantly increased by 63.8%, whereas WDF and C-DF had no significant effects. The three types of degradable film treatments could promote the growth of underground roots, and the growth vigor was obviously enhanced. The yield of pumpkin treated with BDF and C-DF was close to that of CK, and the yield of pumpkin treated with BDF was significantly lower than that of CK by 11.4%. The experimental results showed that the effects of the BDF and C-DF treatments on soil quality and yield were comparable to those of CK. According to the results, two types of black degradable plastic film can effectively replace ordinary plastic film in the high-temperature production season.
Keywords: degradable plastic film; pumpkin; roots growth; soil physical and chemical properties; yield.