| An incubation test with black soil (Phaeozem), Albic soil (Albic Luvisols), brown soil (Cambisols), and cinnamon soil (Chromic Luvisol) from Northeast China was conducted under the conditions of 10%, 20% and30 % field capacity, and the kinetic parameters of soil urease, phosphatase, and arylsulphatase were determined, aimed to study the changes in the catalytic potential of these enzymes under different soil moisture conditions. All test enzymes exhibited typical Michaelis-Menten kinetic behaviors. The test enzymes exhibited the highest enzyme-substrate affinity (l/Km) at 20% or 30% field capacity. With increasing soil moisture content, the Fmax of test soil urease decreased, while that of soil phosphatase and arylsulphatase increased, with the maximum... |
