MICROPLASTICS (ΜPS) AND NANOPLASTICS (NPS) IN FARMLAND SOILS HAVE BEEN MINIMALLY STUDIED, EVEN THOUGH AGRICULTURAL PLASTICS (E.G., MULCH AND HIGH TUNNEL FILMS) BECOME INCORPORATED IN SOIL. NPS, EVEN THOSE FORMED FROM BIODEGRADABLE PLASTICS, CAN RESIDE IN SOIL FOR MONTHS AND YEARS AND CAN POTENTIALLY HARM SOIL BIOTA, SUCH AS BACTERIA AND EARTHWORMS. THE MAJOR GOAL OF THIS PROJECT IS TO MORE DEEPLY UNDERSTAND THE FATE, TRANSPORT AND INTERACTIONS OF ΜPS+NPS IN SOIL AND HOW THEY MAY IMPACT PHYSICAL AND BIOLOGICAL SOIL HEALTH INDICATORS. THIS WILL BE ACHEIVED ACHIEVED THROUGH THREE OBJECTIVES: 1) QUANTIFY THE FATE, INTERACTIONS, AND TRANSPORT OF ΜPS+NPS IN SOIL, 2) DETERMINE THE INTERACTIONS OF ΜPS+NPS WITH MICRO- AND MACROORGANISMS, AND 3) PROVIDE RECOMMENDATIONS FOR MITIGATION OF MPS+NPS FORMED FROM CONVENTIONAL AND BIODEGRADABLE PLASTICS TO RETAIN SOIL HEALTH. THE RESEARCH PLAN LEVERAGES THE PROJECT TEAM'S EXPERTISE IN PREPARING AND CHARACTERIZING ΜPS+NPS AT DIFFERENT SIZE RANGES FROM POLYETHYLENE AND POLYBUTYRATE AGRICULTURAL PLASTIC FILMS, AND UTILIZES AN ARTIFICIAL SOIL EXPERIMENTAL MATRIX SPANNING A RANGE OF COMPLEXITY, FROM SIMPLE HOMOGENEOUS SILICATES TO HETEROGENEOUS SOILS CONTAINING ADSORBED HEMATITE, NATURAL ORGANIC MATTER, AND BIOFILMS. THE METHODS USED INCLUDE SMALL-ANGLE NEUTRON SCATTERING STUDIES TO INVESTIGATE NP-SOIL PARTICULATE INTERACTIONS ON A NANOSCALE, AND TRANSPORT STUDIES OF ΜPS+NPS IN POROUS MEDIA. ALSO, MESOCOSMS TO ASSESS PLASTIC PARTICLE UPTAKE BY MICROORGANISMS AND ITS IMPACT ON ENZYME EXPRESSION, AND INGESTION BY EARTHWORMS. THIS STUDY WILL LEAD TO NEW, SAFER, AGRICULTURAL PLASTICS AND THE FUNDAMENTAL KNOWLEDGE AND METHODOLOGY TO UNDERSTAND THE FATE AND TRANSPORT OF PLASTICS AGRICULTURAL FIELDS.

University Of Tennessee, Memphis TN

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