Metha-BioSol : Impact des digestats de méthanisation sur la qualité biologique des sols agricoles

The Metha-BioSol project aims to assess the impact of anaerobic digestion residues (digestates) on the biological and ecological quality of soils using an operational dashboard of indicators. This dashboard includes measurements of soil physical and chemical status, bio-indicators of soil biological communities and indicators of soil biological functions and soil health status. The project consisted of two parts: 1) To evaluate, under controlled conditions, the impact of different types of digestates taking into account the soil type, and on experimental sites, the impact of repeated digestate applications; and 2) To establish a national network of agricultural farms and conduct an assessment of the impact of digestate application combined with various agronomic practices in different pedoclimatic contexts. The results obtained from both controlled conditions and experimental sites showed that the response of bio-indicators to digestate application was dependent on the type of digestate, the pedoclimatic context, and the recurrence of these applications. The establishment of the farm network also provided the first elements for creating a reference framework for interpreting the impact of digestate use in varied territorial and sociotechnical contexts.