Plastic mulching in agriculture: agronomic performance, residual film hazards, and green development strategies

Agricultural film mulching is a key agronomic practice for improving water and thermal resource use and ensuring food security, particularly in arid and semi-arid regions. However, long-term reliance on conventional polyethylene (PE) films has caused severe plastic pollution, while microplastic accumulation threatens farmland ecological security. This review adopts a critical review approach based on structured literature retrieval and thematic narrative synthesis of agricultural plastic mulching technology. The scope covers mulching materials, agronomic application modes, crop regulation mechanisms, ecological risks associated with residual films, and green transition strategies. Literature published between 2000 and 2026 was retrieved from the Web of Science Core Collection, ScienceDirect, CNKI, and other relevant databases. A total of 2,157 records were initially identified, and 247 studies were finally included for qualitative narrative synthesis after duplicate removal, title–abstract screening, and full-text eligibility assessment. Bibliometric analysis revealed a rapid increase in research output since 2010, with residual film pollution, biodegradable mulch, and soil quality emerging as major research hotspots, highlighting growing concerns over sustainable agricultural plastic management. This review traces the evolution of mulching materials from natural organics to synthetic plastics and emerging environmentally friendly and functionally enhanced materials. It further examines two major agricultural application patterns and the mechanisms through which film mulching regulates crop growth. The review then critically evaluates soil degradation risks associated with residual films, as well as the challenges of mechanized recovery and resource utilization. Based on these findings, a phased transition pathway is proposed. In the short term, priority should be given to optimizing film thickness and strength while improving mechanized recovery and film–impurity separation technologies. In the long term, emphasis should shift toward the molecular design and development of low-cost, high-performance, and controllably biodegradable materials. Overall, this review establishes a multidisciplinary analytical framework integrating material evolution, agricultural application, agronomic regulation, degradation, residual pollution, recovery, and green governance, providing theoretical and practical references for balancing agricultural productivity with ecological protection.