Effect of Hydrological Conditions on Carbon, Nitrogen Vertical Distribution of Typical Alpine Marsh in Zoige

Vertical distribution of soil organic carbon and nitrogen content of seasonal water marsh and perennial water marsh in Zoige was studied with field sampling and laboratory analysis.The results showed that within the range of 0-200 cm soil layer, organic carbon content of perennial water marsh was 270.174 g·kg^-1, and the nitrogen content was 11.963 g·kg^-1.Carbon content of seasonal water marsh was 212.066 g·kg^-1, and the nitrogen content was 10.824 g·kg^-1.Carbon and nitrogen content of seasonal water marsh were less than that of perennial water marsh.In the range of 0-60 cm soil layer, the organic carbon content of 2 kinds of marsh appeared different degree of increase, but the increase amplitude and increase rate of organic carbon content of perennial water marsh was significantly higher than that of seasonal water marsh.In the range of 110-200 cm soil layer, the change of carbon content tends to be stable, but the carbon content of perennial water marsh was obviously higher than that of seasonal water marsh at the same depth.In the surface and middle layer of peat (0-110 cm), the nitrogen content of seasonal water marsh was greater than that of the perennial water marsh.And at the bottom layer of peat (110-200 cm), the nitrogen content of seasonal water marsh was greater than that of the perennial water marsh.The above data demonstrated that the content of organic carbon was decreased in the evolution process from the perennial water marsh to the seasonal water marsh, the carbon sinks function of wetlands has changed.