Seasonal changeability of soil enzyme activity has not been entirely known. The aim of the paper was presenting the seasonal changeability in enzyme activity in fresh forest sites. From 10/06/2007 to 20/06/2008 samples were taken seven times at 6-weeks’ intervals from two sample plots representing sites Lśw, LMśw, BMśw and one for Bśw site. Activity of dehydrogenase, protease and urease have been marked in the soil samples. As a result of conducted research the minimum value for enzymatic activity was found in October 2007 and April 2008. Maximum values for the activity of studied enzymes were noted in January and June 2007 and 2008, while no statistically significant differences were found between enzymatic activity marked in June 2007 and June 2008.

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