By Blake Jackson
Microplastics-tiny plastic fragments smaller than 5 millimeters are increasingly recognized as pollutants in soils, waterways, and even the food chain. Research shows these particles can disrupt soil health, carry other contaminants, and harm aquatic ecosystems.
While urban sources like wastewater have received attention, agricultural lands are now being identified as significant contributors.
In farming, plastics are widely used to boost productivity. Plasticulture using plastics in crop production includes mulch films, drip irrigation lines, greenhouse coverings, and row covers. These tools conserve moisture, suppress weeds, protect crops, extend growing seasons, and improve yields.
However, plastic residues from these applications can fragment into microplastics and persist in soil over time. Other sources include land-applied biosolids, compost, manure, polymer-coated fertilizers, irrigation water, and atmospheric deposition.
Microplastics can alter soil structure, water movement, and the activity of organisms like microbes and earthworms. High concentrations may slow root development, affect nutrient cycling, and interact with other contaminants such as pesticides or heavy metals.
Microplastic surfaces can also host microbial communities, including harmful pathogens, highlighting the importance of good manure management and produce-safety practices.
These particles do not remain confined to fields; they can wash into streams through runoff, tile drains, or wind, contributing to water pollution. Studies show microplastics are now present in agricultural streams nationwide.
In crops, nanoplastics may be absorbed by roots and transported into leaves or edible portions, raising concerns about food safety. Livestock can ingest plastics from feed, water, or soil, potentially entering the food chain via meat, milk, or eggs.
Farmers can mitigate risks by reducing plastic use, choosing durable or reusable materials, promptly retrieving mulch and drip lines, and managing organics carefully.
Implementing conservation practices such as cover crops, buffer strips, sediment basins, and wetlands can help prevent plastic fragments from entering waterways. Monitoring sources like biosolids, compost, and manure for contamination is also critical.
Microplastics are an emerging contaminant with potential impacts on soil, water, crops, and livestock. Thoughtful management of plastics and farm runoff can help reduce environmental and food safety risks.
Photo Credit: gettyimages-casarsaguru
Categories: Pennsylvania, Crops, General