Wild Apples are On the Wane in Central Asia

ON 10/22/2022 AT 08:33 AM

Accelerating temperature rise from the climate crisis may soon force yet another species to extinction. This time it is the wild apple which used to thrive in the mountainous regions of parts of Central Asia.

Wild apples in Kazakhstan

The malus sieversii wild apple species in Zhongar-Alatau, located in Dzungarian Alatau, an isolated, glaciated mountain range in Kazakhstan, Photo: Yakov Federov, CC

The discovery was made by Zhongping Tian of Shanghai’s East China Normal University, and associates working with him to document the rapid population decline of the Malus sieversii species of wild apples in eastern Central Asia.

The research is significant not just to the region but the entire world. That is so because Malus sieversii is a common genetic ancestor to the well-known Fuji, McIntosh, and Granny Smith apple varieties. The Malus sieversii apple is also highly prized for its refreshing taste, unique to this particular species.

Zhongping Tian’s work involved counting thousands of apple trees and mapping their distribution in large sections of Central Asia, including it this species’ native habitat in the mountainous regions of Kazakhstan.

What they found was that just since a little over 30 years ago, an estimated 70 percent of this apple strain’s natural habitat has disappeared. With these wild apples being nearly a genetic monoculture with little biodiversity, they are especially sensitive to changes in their habitats. Apples in general are also highly sensitive to the seasonal temperature condition where they are grown, and these variants are no different.

With average temperatures warming far faster than throughout the Earth as a whole, this has put this species in extreme peril for it existence. The researchers estimate this will push the optimum area where the wild apples will thrive to a location 118-167 kilometers (73-104 miles) further north of where they are now, and also roughly 200 meters (656 feet) higher altitude than currently.

The impact of the climatic changes is significant. While local governmental agencies in the areas where the wild apples are prevalent have taken steps to protect some 13% of the existing habitats from harm, the one thing they cannot do anything about is rising temperatures within those habitats. That is why despite these protections, the researchers in the current study conclude that only one-fourth of the habitat region currently being protected will be able to support this species by the end of the century.

The authors further note that, based on data they have already taken and carrying out further analysis using computer models, the “wild apple will lose all suitable habitats in Zhambyl [region] of Kazakhstan, Tajikistan and Uzbekistan.” In nearby Kyrgyzstan, the expanse covered by this species within existing protected areas will decline by 78% in the same time period.

About the only protected areas where the wild apples will expand is in Kazakhstan and the Xinjiang region of China.

The authors note that, even with that expansion projections the species is still at risk because of the lack of genetic diversity. That is despite that, for other wild fruit variants such as apricots and nut bearing trees such as walnuts, the Central Asian mountain areas are known as a “biodiversity hotpot … one of the most important centers of origin and diversity for temperate wild fruit trees.” Yet because these trees cannot migrate naturally they will need human help.

Those potential extinctions would be a serious economic hit to the countries of Kyrgyzstan, Tajikistan and Uzbekistan, which depend on them as valuable sources of revenue. It is for that reason that many farmers in the area are already working to move their wild fruit orchards further north and into higher altitudes, in response to rising temperatures.