Reducing the carbon and water footprints of Brazilian green coconut

The assessment of the carbon and water footprints of agricultural products is important for fruit producers because it enables improvements in environmental management along the production chain as well as the opening of new markets. This study analyses the carbon and water footprints of green coconut produced in seven farms located at the main producing States in Brazil (Ceará, Alagoas, Sergipe and Bahia), investigating opportunities for reducing these footprints.

The carbon footprint was calculated based on ISO 14067 and the water footprint, on ISO 14046. Primary data were collected from orchards with dwarf coconut trees, located in the states of Ceará (CE1, CE2, CE3 and CE4 farms), Alagoas (AL farm), Sergipe (SE farm) and Bahia (BA farm). The impact categories considered and their assessment models were as follows: (i) for the carbon footprint, climate change impact was assessed (ILCD midpoint); (ii) for the water footprint, water scarcity (AWARE), human toxicity, cancer, non-cancer, and freshwater ecotoxicity and marine and freshwater eutrophication (ILCD midpoint) were assessed. Sensitivity analysis was performed for variations in emissions from land use change (LUC) and water scarcity characterization factors. Uncertainty analysis was applied to identify best performing farms and their practices.

The farms that resulted in lower footprints (AL and CE4) caused less carbon losses in LUC and used less nitrogen fertilizers and irrigation water. LUC emissions answered for one third of coconut carbon footprint when orchards were installed in areas with Caatinga vegetation. However, if coconut orchards replaced annual crops, carbon footprint may reduce up to 61%. Regarding water scarcity, in the case of applying monthly AWARE factors, the impact increased as much as 95% in relation to impacts calculated using annual factors. The use of regionalized annual or monthly AWARE factors increased impact up to 97% in relation to when annual and monthly AWARE were used.

The analysis of alternatives for footprint reduction showed that both footprints can be reduced in all regions with changes in orchard lifespan, irrigation and fertilization. Increasing the useful life of the orchard results in a reduction of up to 38% in footprints, adjusting irrigation, up to 49%, and the amount of fertilizer, up to 70% of the carbon footprint and up to 82% of water footprint profile. Regionalized factors were more accurate for identifying critical watersheds for coconut production.