Controlling environmental factors of soil enzyme activities at three altitudes on Mt. Jumbong

Soil microbes perform crucial roles in the nutrient cycles of forest ecosystems, by effecting the decomposition of organic matter. Enzyme activities have been used to evaluate decomposition rates, as well as microbial activities. The principal objectives of this study were to determine the activities of different soil enzymes, to compare enzyme activities at different elevations, and to elucidate the most important controlling variables for enzyme activities. We conducted a field survey at three sites in Mt. Jumbong on a monthly basis from May, 2004 to September, 2005. Enzyme activities did not change substantially over different seasons. However, the spatial differences were distinct; the lowest elevation site evidenced the lowest levels of enzyme activity. Soils at the lowest elevation were nutrient-depleted soils, and enzyme activities appeared to be affected by precipitation and temperature. However, enzyme activities in fertile soils at high elevations were associated with nutrients and organic matter. The enzyme activities detected in this study differed signifcantly at the three elevations, and their controlling variables also evidenced different factors.