Spatial-temporal distribution characteristics of soil organic matter and total nitrogen in the Jiuduansha wetlands of the Yangtze estuary

The spatial patterns of soil total nitrogen and organic matter was investigated for the Shangsha shoal of Jiuduansha shoals in Yangtze Estuary. Soils had a distinctive seasonal variation in the content of total nitrogen and organic matter, and these changes could be separated into three phases. The soil concentrations of total nitrogen and organic matter were negatively correlated with depth with the surface layer being characteristically accessible, with higher nitrogen content and a wavy surface while the other three deeper layers contained root masses and lower contents of both total nitrogen and organic matter. As expected, the concentrations of soil total nitrogen and organic matter content were positively correlated. This study provides background information for programs involving the environmental protection of the Jiuduansha wetlands.