Plastic Debris in Agroecosystems: Distribution and Abundance Patterns, and Relationship with Terrain Characteristics in Southeastern Brazil

Plastic pollution in agricultural soil is a major concern, affecting soil biodiversity and functionality. In this context, studies of agricultural soil plastic pollution that consider its use across different regions are essential. Considering land use (forest, grassland, and agriculture), this study aimed to identify, quantify, and characterize plastic debris in various agroecosystems within a Southeast Brazil sub-basin. Additionally, the sampled plastic debris was georeferenced, allowing its characteristics to be correlated with terrain features, such as the LS factor and vegetation cover. Based on size, the plastic debris was categorized into macroplastics, mesoplastics, and coarse microplastics. The results revealed that agricultural areas accounted for 91.2% of the total plastic waste collected. The most common polymer types identified were polypropylene, polyethylene, and poly(vinyl chloride), comprising 82.6% of the total. The accumulation of plastic debris in this region was primarily linked to intensive human activity and agricultural practices. Moreover, its distribution strongly correlated with terrain characteristics, particularly the LS factor and vegetation cover, with higher concentrations observed in smooth and moderately undulating terrain. These findings highlight the importance of monitoring plastic debris in the microwatershed terrain and identifying pollution sources to provide valuable insights for mitigating its environmental impact.