A new, global study of plant roots has found that their average rooting depth (depth above which 99% of the global biomass is found) has decreased by 8 cm. This represents a loss of 5%, or 11.6 trillion cubic meters of rooted soil – equivalent to ten times the rooted soil of the entire Mornington Peninsula.

This decrease is largely due to the move to large areas of domestic crops, where root depth has decreased by 60 cm. The result has been a substantial decrease in soil biomass and accessible soil nutrients and a loss of previously available deep soil water.

Projections are that by 2021, the average root depth will have decreased by up to 30 cm, with a loss off 43.5 trillion cubic meters of rooted soil (19% of the global total global).

– Further information and image here.