[Temporal and spatial characteristics of substrate enzyme activities and bacteria physiological groups in constructed...

Six enzymes and five bacteria physiological groups from the substrate (soil) of integrated vertical flowing constructed wetland are chosen to study temporal and spatial characteristics. The research results show that significant differences existed in each enzyme during different months (p < 0.05). The enzyme activities of cellulase, protease and phosphatase were significantly higher in June, September and December than those in March; The enzyme activity of beta-glucosidase in June was significantly higher than those in other months; While urease activities in both September and December were extremely significantly higher than those in March and in June (p < 0.01); But the dehydrogenase was different from the above-mentioned enzymes, which had higher enzyme activities in June and in December than in March and in September. Compared with the temporal characteristics, the spatial characteristics of all six enzymes show consistency: the enzyme activities in the down-flow chamber were significantly higher than those in the up-flow chamber (p < 0.05), and all of the enzyme activities in both chambers were relatively lower with the increasing depths of substrate layers. The numbers of bacteria physiological groups were at peak in June and September and their spatial characteristics were the same with enzyme activities.