Selenium deficiency promoted by climate change

Typography

As a result of climate change, concentrations of the trace element selenium in soils are likely to decrease. Because the selenium content of crops may also be reduced, the risk of selenium deficiency could be increased in many regions of the world. This was shown by a recent study which used data-mining to model the global distribution of selenium.

Selenium is an essential micronutrient obtained from dietary sources such as cereals. The selenium content of foodstuffs largely depends on concentrations in the soil: previous studies have shown that low selenium concentrations are associated with high pH and oxygen availability and low clay and soil organic carbon content. In Europe, as is known from regional studies, selenium-poor soils are found particularly in Germany, Denmark, Scotland, Finland and certain Balkan countries.

As a result of climate change, concentrations of the trace element selenium in soils are likely to decrease. Because the selenium content of crops may also be reduced, the risk of selenium deficiency could be increased in many regions of the world. This was shown by a recent study which used data-mining to model the global distribution of selenium.

Selenium is an essential micronutrient obtained from dietary sources such as cereals. The selenium content of foodstuffs largely depends on concentrations in the soil: previous studies have shown that low selenium concentrations are associated with high pH and oxygen availability and low clay and soil organic carbon content. In Europe, as is known from regional studies, selenium-poor soils are found particularly in Germany, Denmark, Scotland, Finland and certain Balkan countries.

To date, however, little has been known about the global distribution of selenium. Using data mining techniques – involving the assessment of datasets originally collected for other purposes – scientists from Eawag and five other research institutes have now modelled global soil selenium concentrations. The sixteen datasets assessed (1994–2016) comprised a total of 33,241 soil data points. Analysis of selenium concentrations in the top 30 centimetres of soil, together with 26 environmental variables, indicated the dominant role of climate-soil interactions in controlling soil selenium distributions.

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