Biodegradable Plastic Mulch Films: Impacts on Soil Microbial Communities and Ecosystem Functions

Area of Science:

• Agricultural Science
• Soil Science
• Environmental Science

Background:

• Plastic mulch films, including polyethylene (PE) and biodegradable plastic mulches (BDMs), are extensively used in specialty crop production for agronomic benefits.
• BDMs present a sustainable alternative to PE mulches, designed to biodegrade after incorporation into the soil.
• Uncertainty exists regarding the long-term ecological consequences of incorporating BDMs into soil ecosystems.

Purpose of the Study:

• To review and synthesize existing literature on the impacts of plastic mulches, with a focus on BDMs, on soil biological and biogeochemical processes.
• To identify knowledge gaps concerning the effects of BDMs on soil health and agroecosystem sustainability.

Main Methods:

• Literature review of studies investigating the effects of plastic mulches on soil microbial communities, microclimate, and biogeochemical processes.
• Analysis of findings on how BDMs influence soil ecosystems both as a surface barrier and as an incorporated material.

Main Results:

• Plastic mulches, when used as surface barriers, modify soil microbial community composition and function through microclimate alterations.
• Incorporation of BDMs into soil can stimulate microbial activity and increase the abundance of fungal taxa.
• The impact of BDMs on soil ecosystems involves physical fragmentation, introduction of carbon, microorganisms, additives, and chemicals.

Conclusions:

• BDM incorporation may stimulate microbial activity, potentially influencing soil organic matter dynamics despite minimal carbon input.
• Further long-term studies are essential to fully understand the impacts of BDMs on nutrient biogeochemistry.
• A comprehensive understanding of BDM effects is critical for assessing their role in promoting soil health and sustainable agroecosystems.