| Discussion is made about the characters of soil enzyme (urease, phosphatase, ucrase) activities of Caragana Koeahinakii Kom.forest land at Shanghuang experimental field in Guyuan County and comparison is conducted of the enzyme activities of different slope aspects, different slope positions, different tree ages and different depths of soil profile.The results showed that slope aspects had no notable influence on soil enzyme activities but the slope positions influenced obviously the soil enzyme activities, and the enzyme activities of the upper slope positions are generally higher than lower slope positions.The soil enzyme activities enhanced as the tree ages increasing and fell down as the depth of soil profile increasing.The phosphatase and ucrase had concerted reaction during the humification of soil organic matter. |