Phosphorus in Peat Soils and Risk for Leaching After Rewetting of Drained Peatlands

Authors:
Maarit Hyvärinen, Pirkko Mustamo, Anna-Kaisa Ronkanen and Bjørn Kløve

Book:
Proceedings of the 14th International Peat Congress

Venue:
Stockholm

Keywords:
land-use, phosphorus-in-peat, phosphorus-leaching, restoration

Documentfile:
Hyvärinen et al 2012: Phosphorus in Peat Soils and Risk for Leaching After Rewetting of Drained Peatlands

Summary:

Theme III. Agricultural use of peat and peatlands

SUMMARY

The effect of land-use on phosphorus in peat soils and risk for phosphorus leaching during rewetting of the site was studied in this research. Peat samples were taken from peatlands with different land uses. Samples were taken from cultivated site, peatland forest, peat extraction site and pristine mire at different depths. The samples were analyzed for easily soluble phosphorus, aluminum, iron and calcium bound phosphorus by Chang and Jackson sequential fractionation method. The risk of phosphorus leaching was estimated in desorption experiments and by measuring degree of phosphorus saturation (DPS). The cultivated site showed high total concentrations of P, Fe and Al compared to other land uses. P fractionation showed that inorganic P in the cultivated site was mainly associated with iron and aluminum. The degree of phosphorus saturation (DPS) measured in the surface of the cultivated site was high (25.6 %) indicating high risk for P leaching, which was also seen in the desorption test.