The pH(H2O) values ranged between 5.5 and 6.5 in all treatments and exposure periods. The initial OM content was 5.4% for control soils and 6.7% for the Cu contaminated soil. For both control and contaminated soils the OM content decreased by about 10% over the 84 days of exposure at the two lowest temperatures (10 and 14 ◦C). For the two highest temperatures (19 and 23 ◦C) a 10% reduction was seen for systems exposed during 28 days but no reduction was observed when systems were exposed for 61 and 84 days.