From soil to sand: Spain’s desertification threat increases

If climate change models are correct, much of Spain’s fertile land will turn to desert.

Spain’s surface is turning into desert according to scientists. 

A new study from the University of Alicante warns that arid (dryland) areas such as Alicante, Murcia, Almería and the Canary Islands, will face increasingly dramatic landscape changes due to climate change.

Arid areas (dryland) make up approximately 45 percent of the world's non-aquatic land and provide livelihoods through activities such as agriculture and livestock farming, for about 2.5 billion people. These areas are particularly sensitive to climate change and experts say it is vital to understand what types of transformations this type of land is facing. 

Despite previous assumptions, changes will not be gradual. Abrupt and “drastic” desertification is the primary prediction. 

The most vulnerable areas are those that currently have a arid climate. Experts say that particularly arid areas across Spain such as Alicante, Murcia and Almeria, along with islands including Lanzarote and Fuerteventura are at most risk of rapid desertification. 

"The fundamental properties of arid ecosystems, such as the productivity of their vegetation or the fertility of their soils, respond in a non-linear way to increases in aridity, such as those expected with climate change," says Fernando Maestre, director of the Arid Zones and Global Change Laboratory at the University of Alicante.

Desertification predictions due to climate change come as no surprise, but scientists say that this new research adds to increasing concerns. 

By the year 2100, up to 18% of earth’s land is predicted to be desert. 

In Spain’s case, approximately 75% of its land will be severely affected by desertification. 

The experts detected three critical levels, or ‘thresholds’ in relation to ecosystem aridity, considered as “situations of no return” Each time an aridity threshold is reached, this increasingly accelerates the process of desertification. 

The first of the identified thresholds refers to aridity levels with a value of 0.54, according to scientists. This corresponds to levels of aridity similar to the current Mediterranean climate. Once this level is exceeded, the productivity potential of land begins to rapidly decline, meaning agricultural cultivation is under threat - and places land into the second threshold of aridity (0.7). Maestre explains this second threshold has "similar conditions to those found in the southeastern part of the Iberian Peninsula.”

The third and most devastating threshold describing aridity levels of 0.8 or above, is the stage of  "a drastic fall in the coverage and diversity of plants, which leads to the appearance of deserts", Maestre continued. 

Life-giving activities like agriculture, when done in an unsustainable way - on dry, vulnerable land, threaten to leave earth barren. According to the United Nations, each year, the world loses 24 billion tons of fertile soil, yet it takes hundreds to thousands of years for just one centimetre of soil to form.

The study analysed a large amount of data on current drylands, in order to assess how their properties change according to their levels of aridity. 

The findings of this study are significant as it will help scientists gain a better understanding of the impacts of climate change on dryland ecosystems. This evidence could help establish mitigation actions, to reduce climate change impacts.

“While we will not stop climate change, I believe we still can minimise its negative consequences on these ecosystems. By collating information on how vegetation and soil properties change as aridity increases, and by mapping those areas most sensitive to such increases, our results can be used to optimise monitoring and restoration efforts, preserve biodiversity and avoid the desertification of these ecosystems”, Maestre concludes. 

Around 38% of the global population live in dryland areas and productivity capacity is already under significant threat. Any mitigation opportunities could help preserve valuable fertile land and protect arid landscapes like those present in Spain from total devastation. 

Katie Burt

Katie Burt

When not found with a laptop at my fingertips, it's likely I'll be running, swimming, attempting to cycle or seeking out decent coffee.

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