National Wetland Condition Assessment 2011: Exploring Relationships Between Soil Properties and Ecological Condition of Wetlands.

To assess the ecological condition of wetland resources across the conterminous United States, the US Environmental Protection Agency and its federal, state, and tribal partners conducted the first National Wetland Condition Assessment (NWCA) in 2011. NWCA is part of the National Aquatic Resources Surveys completed by EPA to improve understanding of the quality of the nation’s waters. A goal of NWCA was to identify and develop indicators of ecological condition, which were evaluated in relation to measures of stress, disturbance, and reference condition. NWCA sites were selected using a probability based design, such that the sites selected and results reflect the full range of wetlands in the target population. Field crews sampled 1,138 wetland sites across the US, collecting data on vegetation, soils, water chemistry, algae, hydrology, and the wetland buffer. This study builds upon the work of NWCA 2011, examining relationships between ecological condition and soil parameters measured at each site. The objective is to identify properties associated with soil health that could be used as indicators of condition or stress in wetlands. Wetland soil quality indicators may be a useful assessment tool in future iterations of NWCA, as well as in state and regional wetland monitoring and assessment efforts. NWCA 2011 also provides a baseline description of soil properties in wetlands nationally, allowing for change and trend analyses in subsequent surveys.