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NATIONAL RESULTS FROM THE 2011 NATIONAL WETLAND CONDITION ASSESSMENT (NWCA) SOILS ANALYSIS
Nahlik, A., M. Kentula, T. Magee, AND A. Herlihy. NATIONAL RESULTS FROM THE 2011 NATIONAL WETLAND CONDITION ASSESSMENT (NWCA) SOILS ANALYSIS. Presented at Joint Aquatic Sciences Meeting, Portland, OR, May 18 - 23, 2014.
In 2011, US Environmental Protection Agency conducted the first National Wetland Condition Assessment (NWCA). Field crews conducted one-day surveys of over 1000 wetlands across the contiguous United States. For every wetland sampled, soils were collected by layer (i.e., horizon) to a depth of 120 cm, described, characterized for bulk density, and analyzed for major nutrients, trace elements, and heavy metals. We analyzed soil data from 1039 wetlands, using this dataset to quantify stressors such as, high concentrations of nitrogen (N), phosphorus (P), arsenic (As), cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn). Preliminary analyses showed that measured concentrations ranged from “below detection” to a maximum of 4.57% Total N, 561 mg Mehlich-P kg-1, 115 mg As kg-1, 12.3 mg Cd kg-1, 548 mg Cu kg-1, 1509 μg Hg kg-1, 401 mg Pb kg-1, and 1827 mg Zn kg-1. Bulk density measurements ranged from 0.05 – 2.5 g cm-3. Our objective is to summarize our findings and report the relative risk to wetlands by Cowardin type and aggregated ecoregion, and across the Nation.
Soil characteristics and chemistry are new indicators for EPAs National Aquatic Resource Surveys. Soils were added to the first National Wetland Condition Assessment because soil is found in all wetlands but water, the usual chemical indicator, is not. As a result, the analyses and research related to the soils data is cutting edge in the field of large-scale wetlands monitoring and assessment.
URLs/Downloads:2014 JASM - NAHLIK ET AL_ USE OF SOILS DATA IN NWCA_FINAL.PDF (PDF,NA pp, 76.229 KB, about PDF)
Record Details:Record Type: DOCUMENT (PRESENTATION/ABSTRACT)
Organization:U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LAB
WESTERN ECOLOGY DIVISION
FRESHWATER ECOLOGY BRANCH