Soil selenium levels set to crash

New research, carried out at Rothamsted in the UK, has found that selenium concentrations in soils across the world are significantly affected by the weather and, if predicted changes in the climate do occur, levels will decrease in many areas.

In Europe, selenium concentrations are predicted to drop by more than 10%.

Courtesy of the Rothamsted work, soil selenium concentrations measured in 15 datasets from different parts of the world were laid on top of 26 variables describing soil, climate and vegetation properties in addition to land cover type, population density, geology, irrigation and soil erosion and other factors.

Based on this model, the climatic factors were identified as the most important factor in soil selenium concentrations. Using this, the first ever global soil selenium concentration estimates were made for the years 1980-1999.

Given the importance of climate on soil selenium concentrations, predictions were then made for the years 2080-2099 to show how climate change could influence global soil selenium concentrations by the end of the 21st century.

Approximately 60% of all modelled areas were predicted to experience a mean loss of selenium of 8.4%.

The effect is more pronounced in agricultural areas, where 66% of modelled croplands were predicted to lose 8.7% of current soil selenium levels, and 61% of modelled pasture lands were predicted to lose 8% of current soil selenium levels.

Professor Steve McGrath, Head of Department of Sustainable Soils and Grassland Systems at Rothamsted Research said that by developing a model that can track changes in the levels of minerals crucial to our nutrition, we are laying the groundwork for a solution to hidden hunger.

“This model has already revealed a very important fact: that climate can be a key factor in the distribution of some essential micronutrients across the globe.”