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Moreover, the weathering of Ca- and Mg-silicate minerals play a central role in the global carbon cycle.   The Ca and Mg, released by the weathering process, will be locked up as carbonates in marine sediments \citep{Sundquist_1985}.   On the long-term, atmospheric CO₂ CO₂  is regulated by the weathering rates of these minerals, which is influenced by climate and mountain uplift \citep{Berner_2003, Raymo_1992}. The vast amounts of nutrients locked in soil minerals has triggered, nearly 100 years ago, the question if plants can actively enter this potential nutrient source \citep{HALEY_1923,TURK_1919}.   Five decades later, studies appear on the role of microorganisms, including mycorrhizal fungi, in mineral weathering \citep{WEBLEY_1963,DUFF_1963,Sperber_1958,Boyle_1967,Boyle_1973}.