Laboratory experiments on the retention of micronutrients by peat humic acids

Summary The retention of some plant micronutrients (Cu, Zn, Mn, Mo) by insoluble peat humic acids has been quantitatively determined by laboratory investigations. The findings support the view that the symptoms of deficiency of these nutrients in plants growing on drained moor or peatland soils could well be caused by such retention. In addition a strong retention of Co was observed which could be the cause of the well-known Co-deficiency in animals feeding on Co-deficient plant material.