Nitrification and Denitrification Potentials of Soil in Liaohe Estuary Wetland

Nitrification and denitrification plays an important role in the nitrogen cycle in wetlands. The nitrification and denitrification potentials of soil from different depths (0-40 cm) in Liaohe estuary wetland were studied with laboratorial batch incubation for three weeks. The results showed that the percent of nitrification and denitrification in soil at different depth were about 25-40% and 31-63% of soil total added nitrogen over three weeks, respectively. Both the denitrification and nitrification of soil at different depth showed an exponential decay trend over the incubation period. The corresponding rates were 0.013–0.021 mg·kg-1·d-1 and 0.017–0.057 mg·kg-1·d-1. The value of surface soil (0-5cm) was significant higher than that of the subsoil (5-40 cm) (p < 0.05) and there was no significant difference between values of the subsoil (p > 0.05).