Regenerative practices can lead to carbon-negative orange groves in Sicily

Abstract

Climate neutrality within European Union (EU) boundaries by 2050 is an ambitious goal set by the European Commission, with carbon sequestration in soils a key mechanism identified to achieve this. While row crops predominate, around 1.3 million hectares (ha) of land in the EU are dedicated to orchard fruit trees. Italy is second only to Spain in total citrus production area (about 22 %) with revenues of more than half a billion dollars and a planting area of nearly 90,000 ha in Sicily alone, the main orange-producing area in Italy, accounting for approximately 63 % of the total production of the country. Despite their environmental and economic importance, soil carbon studies in these systems are extremely rare. In our 13-year study, we compared the carbon balance (CB) of orange groves that were managed using either conventional (CON) or regenerative (REG) practices. We adopted the SALUS-crop model to determine soil organic carbon (SOC) sequestration and the Carbon Footprint (CF) methodology set by ISO standards to calculate greenhouse gas (GHG) emissions. The CB in the CON groves was 5.44 Mg CO₂-eq ha⁻¹ yr⁻¹ (SOC sequestration lower than GHG emissions) while in the REG groves it was −0.61 Mg CO₂-eq ha⁻¹ yr⁻¹ (SOC sequestration greater than GHG emissions). Specifically, CON loses SOC at 1.23 Mg CO₂-eq ha⁻¹ yr⁻¹ while REG sequesters SOC at 1.68 Mg CO₂-eq ha⁻¹ yr⁻¹. Our study shows that regenerative management in orange groves can convert the soil from a carbon source to a carbon sink, and that the CON and REG systems act as an overall GHG emissions source and GHG emissions sink, respectively. Increased soil carbon sequestration in citrus groves will contribute to the EU climate neutrality goal and can offer opportunities for farmers to benefit financially for their improved land stewardship.