Utilization and Management of Agricultural Wastes for Bioenergy Production, Weed Control, and Soil Improvement Through Microbial and Technical Processes

The utilization and management of agricultural wastes for plant growth and fertilization or crop production and protection purposes can facilitate the transition of current agricultural systems or “productivism agriculture” to a post-productivism agriculture or “production of nature” era. The availability of agricultural wastes, a theoretical estimation indicates that approximately 3.5–17.0 billion tons of agricultural wastes can be produced worldwide, in combination with the various technologies for the conversion of these wastes to bioenergy are significant factors that enhance the value of this type of feedstock. In addition, the role of agricultural wastes as mean for weed control (e.g. maize gluten meal, Brassicaceae seed meal, abrasive grit), soil amendments and fertilizer substitute (e.g. abrasive grit, biochar, Brassicaceae oilseed meal, digestate from anaerobic digestion), or plant growing medium (e.g. composts) signifies the added value of these materials toward sustainable production systems. Nevertheless, the utilization of agricultural wastes should not disturb the soil carbon and other nutrients dynamics. This can be avoided by setting appropriate limits and continued monitoring, hence, reducing uncertainty about their beneficial environmental performance.