Effects of Cu pollution on soil alkaline phosphatase activity

Effects of Cu from earth samples of different depth on alkaline phosphatase(ALP)activity and dynamic parameters were analyzed.It was found that ALP activity increased with incubation,ALP activities of surface sample and sample with 50 cm depth firstly rose,and then declined with increasing Cu concentration,while ALP activities of sample with 100 cm depth decreased.Variations in changes of enzyme activity in samples were a result of different physical and chemical properties,especially organic matter content.Effects of Cu on Vmaxand Vmax/Kmwere significant,and Vmaxand Vmax/Kmmight serve as assisted reference index for evaluation of Cu pollution degree.Cu inhibition of ALP activity displayed a complex non-competitive and competitive mode.