Long-term fate of rapidly eroding carbon stock soil profiles in coastal wetlands

Marsh edge erosion is one of the major causes of land and associated carbon loss in wetland-dominated coastlines. Assessing carbon stocks and understanding fate of eroding carbon is an essential component of wetland carbon budget. This study aims to understand the vertical soil carbon profile of an eroding marsh and potential mineralization of carbon in estuaries. Eleven soil cores (~2 m deep) were collected from the edge of four highly eroding marsh sites and three cores from the estuarine bottom (~50 cm deep). Cores were sectioned into 10-cm intervals and analyzed for total, labile and refractory carbon, carbon density, select enzyme and microbial activities, and organic and inorganic phosphorus forms. The total carbon, labile carbon, and carbon density increased with depth at all sites. The carbon density at 1–1.5 m deep (0.04 ± 0.003 g cm−3) was significantly higher (p