Carbon and nitrogen storage of a restored wetland at Illinois’ Emiquon Preserve: potential for carbon sequestration

Abstract

Conversion of wetlands to croplands results in the release of a significant amount of carbon (C) from soil organic matter (SOM) into the atmosphere. Restoring wetlands from croplands has C sequestration potential. The overall goal of our study was to quantify C and N storage of a restored wetland at the Emiquon Preserve, and examine its potential for C sequestration by comparing its C storage with C storage of reference natural wetlands in Illinois. Samples of plants and soils at the restored wetland and four reference wetland sites were collected in 2009 and 2011, respectively. We found that ecosystem storage of organic C (OC) and total N (TN) of the restored wetland was 38.29 Mg C ha−1 and 2.43 Mg N ha−1, respectively. For the reference sites, the average ecosystem storage of OC for sedge meadow and marsh was higher at 136.63 and 52.04 Mg C ha−1, respectively. The soil OC (SOC) storage of the restored wetland was only about 25% of SOC storage of reference sedge meadow sites and 46% of reference marsh site, suggesting that the restored wetland at Emiquon has the potential to sequester a large amount of additional C in the future.