Ecological Roles of Biodegradable Mulch Film on Soil Nutrients and Microbes

Biodegradable mulch film (BDM) is increasingly promoted as a sustainable alternative to conventional polyethylene mulch film because it can degrade in soil after agricultural use. However, current evaluations mainly focus on degradation efficiency and crop productivity, often assuming that biodegradation automatically implies ecological safety. Here, we argue that this assumption is incomplete. Rather than acting as a passive substitute, BDM degradation represents a temporally structured ecological disturbance that actively alters soil microbial metabolism, extracellular enzyme stoichiometry, nutrient cycling, and rhizosphere function. We propose that the ecological consequences of BDM are primarily determined by whether polymer degradation is synchronized with microbial succession and crop nutrient demand. This perspective shifts the evaluation of BDM from degradation efficiency and economic benefit toward ecosystem functionality and provides a new theoretical framework for designing next-generation biodegradable agricultural materials.