Study: Traditional Olive Groves Absorb More Carbon than Intensive Ones

As part of Project OLIVEN, a research team from the University of Jaén has con­cluded its study into the envi­ron­men­tal impact of both tra­di­tional and inten­sive extra vir­gin olive oil pro­duc­tion.

Its find­ings show that tra­di­tional olive groves absorb sig­nif­i­cantly more CO2 than those using inten­sive (high-den­sity or super-high-den­sity) farm­ing meth­ods.

The study also pro­vides a com­pre­hen­sive break­down of the impact of spe­cific stages in the extra vir­gin olive oil pro­duc­tion cycle by eval­u­at­ing the car­bon foot­print, car­bon bal­ance and envi­ron­men­tal impact of four tra­di­tional rain-fed, four irri­gated and three inten­sive olive farms in Spain, plus 12 olive oil mills.

This includes the eval­u­a­tion of water and energy use, fer­til­iza­tion, insec­ti­cide appli­ca­tion and waste treat­ment through­out the cycle, from tree cul­ti­va­tion to olive trans­for­ma­tion.

While the team con­cluded that (unpack­aged) extra vir­gin olive oil pro­duc­tion is mostly car­bon-neg­a­tive and that all three cat­e­gories of olive groves act as CO2 sinks, tra­di­tional groves were revealed to be far more cli­mate-friendly.

“[These groves] allow 5.5 kilos of CO2 equiv­a­lent to be removed from the atmos­phere for each kilo of oil finally pro­duced,” said Lázuli Fernández, the study’s lead author. ​“In the case of irri­gated cul­ti­va­tion, this value drops to 4.3; and the inten­sive method allows cap­tur­ing up to 2.7 kilos of CO2 equiv­a­lent for one kilo of oil.”

“To reduce the impact of vir­gin olive oil pro­duc­tion, most efforts should be focused on the farm­ing phase,” he added.

This fol­lows the find­ing that the farm­ing phase of the extra vir­gin olive oil pro­duc­tion process accounts for 76.3 per­cent of the total envi­ron­men­tal impact in the cli­mate change cat­e­gory.

Associated neg­a­tive envi­ron­men­tal impacts were also high­est in inten­sive olive groves, mostly due to the appli­ca­tion of nitro­gen fer­til­iz­ers, plant pro­tec­tion prod­ucts and her­bi­cides.

The team rec­om­mended that a num­ber of tech­ni­cally and eco­nom­i­cally viable changes be made in order to mit­i­gate neg­a­tive envi­ron­men­tal and cli­mate changes.

“The appli­ca­tion of organic fer­til­iz­ers and facil­i­tat­ing tem­po­rary spon­ta­neous cover crops achieve a pos­i­tive car­bon bal­ance and reduce the neg­a­tive impacts of olive cul­ti­va­tion,” Fernández said.

Coming as it does dur­ing a grow­ing trend towards inten­si­fi­ca­tion in olive pro­duc­tion, the study raises fur­ther con­cerns about the sus­tain­abil­ity of cer­tain mod­ern prac­tices in the sec­tor.

According to the Spanish gov­ern­ment, Andalusia, the largest olive oil-pro­duc­ing region by far and home to most of the world’s high­est-inten­sity olive groves, is among the ter­ri­to­ries most at risk of seri­ous envi­ron­men­tal dam­age from the shift away from tra­di­tional farm­ing meth­ods.

This trend also is not con­fined to Spain. The Italian Ministry of Agriculture recently approved a €30 mil­lion invest­ment fund to finance the mod­ern­iza­tion of the country’s olive groves. One of the stated aims of the fund is to increase the use of irri­gated cul­ti­va­tion, shown by this study to increase neg­a­tive envi­ron­men­tal impacts and decrease cli­mate change mit­i­ga­tion.

Project OLIVEN is not only con­cerned with reduc­ing the envi­ron­men­tal impact of olive oil pro­duc­tion, how­ever. Through inter­na­tional coop­er­a­tion, the project also aims to iden­tify and develop new rev­enue streams by exploit­ing the sector’s waste and by-prod­ucts.

To this end, the team is now turn­ing its atten­tion to the poten­tial eco-friendly eco­nomic ben­e­fits that could be cre­ated via bio­mass gas pro­duc­tion. Through such research, the mem­bers hope to improve long-term sus­tain­abil­ity both eco­log­i­cally and eco­nom­i­cally.

• University of Jaén
• Journal of Environmental Management