COVER CROP CARBON SEQUESTRATION POTENTIAL AND ASSOCIATED TRADE-OFFS: THE OLIVE TREE DEBRIS AS FEEDSTOCK OF A LOCAL BIO-REFINERY CASE STUDY

Biomass residues use in circular economy is aimed to get significant GHG emission reductions to tackle against climate change. Olive pruning debris, in Andalusia region, is commonly used (50%) as inert cover on field to protect against erosion and to provide nitrogen and carbon to the soil. The installation of a local bio-refinery using olive pruning residues as feedstock could be a good example of circular economy application enhancing sustainability of goods produced and improving local economy. However, the conversion of the residue into a raw material generates a change in the agriculture management with negative consequences on soil carbon sequestration. The paper analyses the living cover crops plantation function as a mitigation strategy to improve carbon sequestration in olive groves combined with the use of olive pruning residues in a bio-refinery. The paper analyses the function of the living cover crops as a mitigation strategy to improve carbon sequestration in olive groves combined to the use of olive pruning residues in a bio-refinery. The main conclusion of the study is the bio-refinery systems analyzed save GHG emissions in all the cases. The selected cover crop specie is of high relevance in the GHG balance.