Microplastics in Agricultural Soils

Plastics have revolutionised our daily lives. Their versatility, low-cost of production, light weight and resistance justify their presence in a vast variety of products. In agriculture, plastics are mainly used to develop and maintain specific microclimate conditions needed for improving plant development. This technological revolution has allowed that infertile lands characterized by a drastic desertification process, adverse climatic conditions, or with a high pest pressure, be transformed in highly productive areas able to boost local/regional economic growth. Traditionally, soil physicochemical properties have been the primary endpoints to assess the impact of agricultural plastics on soil. However, the effects of plastic debris and microplastics on soil biota is gaining a growing concern. In this chapter, the authors discuss the current knowledge on the potential impact of microplastics on agricultural soils under a biological perspective. The first section describes the main applications of polymeric-based materials in agriculture, particularly horticulture, which may pose a significant source of plastic contamination. A second section summarises the main routes of plastic input in agricultural soil. The last section will discuss the main uncertainties regarding the occurrence of microplastics in the soil system, and what are the research areas that will require further investigation.