Plastic has become an indispensable material in modern agriculture due to its low cost, versatility, and durability, and its use, despite representing a relatively small share of global production, significantly impacts agroecosystem functioning. In agricultural practice, plastics contribute to higher productivity and more efficient natural resource use, while also acting as a source of soil contamination, as they accumulate during aging and degradation in the form of smaller particles that can enter aquatic and food chains. This article aims to evaluate current knowledge on the sources, pathways, and environmental impacts of microplastics (MP) in agricultural soils. Major sources of plastic particle input into soils include the application of composted and fermented organic residues, sewage sludge, irrigation with treated wastewater, and the degradation and incorporation of plastic mulches, as well as leaching from improperly managed waste disposal sites. Once incorporated into soils, plastic particles interact with mineral and organic components, becoming part of the soil matrix and potentially altering soil bulk density, aggregate stability, water retention capacity, and hydrophobicity. Special attention is given to the use of plastics in vegetable production, where greenhouse and tunnel coverings, mulching films, and irrigation systems play a key role in regulating microclimatic conditions and stabilizing yields. A review of the literature indicates that even biodegradable materials frequently fail to achieve their expected degradation rates under field conditions, highlighting the need for comprehensive evaluation of materials and the development of sustainable and responsible agricultural practices to mitigate soil plastic contamination.
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