PEAT AS A NATURAL COMPLEXING AGENT FOR TRACE ELEMENTS

The complexing properties of peat have been demonstrated in two different series of experiments.
Zinc, Cd⁺⁺, Cu⁺⁺ and Pb⁺⁺ were added to peat suspensions and to purified peat humic acids and equilibrated at different pH.

It was shown that the retention of this metal ions increased with increasing pH and that the selectivity of peat decreased in the following way Cu⁺⁺ > Pb⁺⁺ > Cd⁺⁺ > Zn⁺⁺ which coincided with the stability of the peat humic acid-metal complexes as determined by a stability index.
For the conditioning of peat as a growth medium Ca⁺⁺-ions are necessary to keep the humic complexes flocculated.

Symposium on Substrates in Horticulture other than Soils In Situ

M.G. Verloo

https://doi.org/10.17660/ActaHortic.1980.99.7