Native Andalusian Olive Varieties Could Be Wiped Out by 2100, Researchers Warn

The amount of land suit­able for olive cul­ti­va­tion will steadily decrease in Andalusia over the next 80 years, accord­ing to a study from the University of Córdoba, the Center for Research in Geo-Space Sciences (CICGE) and the University of Porto.

While the Picual vari­ety — which is used to pro­duce nearly one-third of the world’s olive oil — and inten­sive farms will be impacted the least, tra­di­tional pro­duc­ers who grow nar­rowly-dis­trib­uted olive vari­eties asso­ci­ated with protested des­ig­na­tions of ori­gin (PGIs and PDOs) could be wiped out.

Using a tool known as species dis­tri­b­u­tion mod­el­ling (SDM) to pre­dict areas suit­able for cer­tain species to sur­vive and thrive based on envi­ron­men­tal char­ac­ter­is­tics, the researchers found that Andalusia’s increas­ingly hot and dry cli­mate is dri­ving the reduc­tion.

“The study reveals that there will be a reduc­tion in the area avail­able for cul­ti­va­tion of most of the olive vari­eties stud­ied,” Salvador Arenas-Castro, a researcher at CIGCE, said. ​“It will be mainly due to the decrease in rain­fall and the loss of soil mois­ture.”

Arenas-Castro and his col­leagues cre­ated mod­els for seven olive vari­eties and wild olive trees, using eight pre­dic­tive vari­ables. They found that six of the vari­eties along with wild olives would have sub­stan­tially less land suit­able for their cul­ti­va­tion by the end of the cen­tury.

“Except for Picual, for which there was an incre­ment in a suit­able area for the future sce­nar­ios, the future suit­able areas pre­dicted for each vari­ety were sig­nif­i­cantly smaller than the cur­rent ones,” the researchers wrote. The land suit­able for grow­ing Picual, on the other hand, is expected to increase by 25 per­cent by 2100.

“This sit­u­a­tion endan­gers tra­di­tional vari­eties, a source of genetic diver­sity that might be very use­ful under new and unfore­seen sce­nar­ios of cli­mate change, dis­eases or pests, or to obtain new vari­eties of olive trees adapted to the new and inno­v­a­tive cul­ti­va­tion tech­niques,” the researchers added.

The Lechín, Manzanilla, Nevadillo, Hojiblanco and Picudo vari­eties are expected to have a 100 per­cent decrease in suit­able cul­ti­va­tion land area by 2100. The Acebuche and Verdial vari­eties are expected to expe­ri­ence a decrease of 72 per­cent and 22 per­cent, respec­tively, over the same time period.

Arenas-Castro warned that the poten­tial loss of olive vari­eties would have a range of con­se­quences for both the land and the peo­ple farm­ing it.

“Most of these endemic vari­eties are grouped within the type of olive cul­ti­va­tion called ​‘tra­di­tional’ that are more related to remote areas or dif­fi­cult-to-access moun­tain areas, which in turn are less pro­duc­tive,” he told Olive Oil Times.

“This type of crop, ahead of the inten­sive or super-inten­sive, har­bors not only an inter­est from the agroe­co­log­i­cal view­point (for the asso­ci­ated bio­di­ver­sity it hosts) but also from the socioe­co­nomic con­text and at a more local scale since it rep­re­sents the sus­te­nance of the econ­omy of regions that would hardly have access to other types of land man­age­ment,” Arenas-Castro added.

Nearly every olive-grow­ing province in Andalusia will be impacted with sig­nif­i­cant decreases pre­dicted in Cádiz, Córdoba, Huelva, Málaga and Sevilla. Jaén is expected to be largely unaf­fected while the moun­tain­ous regions of Granada and Almería will become increas­ingly hab­it­able for Picual olives.

Andalusia’s chang­ing cli­mate is also likely to lead to a decrease in the over­all quan­tity of arable land in the autonomous com­mu­nity. As crop dis­tri­b­u­tion steadily changes over the cen­tury, those that have not tra­di­tion­ally over­lapped may begin to do so, which could bring farm­ers into con­flict.

“Changes in the envi­ron­men­tal areas of this crop would affect its redis­tri­b­u­tion to other areas, and may con­flict with other types of crops that are cur­rently being used, such as cere­als, and there­fore caus­ing poten­tial con­flicts,” Arenas-Castro said.

“In this sense, know­ing the pos­si­ble changes that may occur in the near future due to loss of poten­tially arable envi­ron­men­tal area, or redis­tri­b­u­tion of the crop, and there­fore over­lap­ping with other crops, allows these dynam­ics to be antic­i­pated in deci­sion-mak­ing,” he added.

Arenas-Castro hopes the mod­els can be used by local gov­ern­ments to begin plan­ning for the future. He believes that addi­tional stud­ies should be under­taken to iden­tify olive vari­eties with sim­i­lar attrib­utes to Picual which may be able to thrive in Andalusia in the future.

“This mod­el­ing frame­work allows us to pre­dict poten­tial changes in the relo­ca­tion of envi­ron­men­tal areas for olive vari­eties, which in turn means that this ​‘early-warn­ing sys­tem’ is very use­ful to mit­i­gate the effects of these changes,” he said. ​“Therefore, con­sid­er­ing that the pre­dic­tions are made in the medium-to-long term, I think that the olive grow­ers, but much more the pol­i­cy­mak­ers, have enough time to take action.”