%0 Research Notes %T Extractable copper in cultivated organic soils %A Jokinen, Raili %A Urvas, Leila %A Hyvärinen, Seppo %D 1993 %J Suo - Mires and peat %V 44 %N 1 %U http://suo.fi/article/9726 %X The content of acid (pH 4.65) ammonium acetate-EDTA (AAAc-EDTA) extractable Cu was in mould soils (9.6 ±5.7 mg/1 soil) about one and a half times that in peat soils (6.6 ± 4.4 mg/1). There was a close positive dependence between extractable Cu and the total Cu in both soil types. The proportion of extractable Cu on the total Cu was in mould soils (wet combustion 40.0 ± 13.3%; dry ashing 40.9 ± 11.3%) somewhat lower than in peat soils (wet combustion 47.4 ± 13.6%; dry ashing 53.4 ± 19.5%). In mould soils the decrease in soil acidity had an increasing effect on both extractable Cu and total Cu contents of soil. In peat soils the extractable Cu and total Cu contents were lowest between pH(H20) values 5.0 and 5.5, and increased with both increasing and decreasing the soil acidity. The extractable Cu and total Cu contents were highest in mould soils of low humus content and in peat soils having humus content between 60 and 70%. Keywords: Humus, mould soil, peat soil, pH, total copper