Imperiled Ecosystems in a Shifting Climate
2016 Atlantic White Cedar Symposium
May 24-26, 2016

Hotel 1620, 180 Water St., Plymouth, MA

Dendroecological analysis of Atlantic White Cedar as a predictor of historic hydrologic conditions in Mid-Atlantic peatlands

J. Slater, A. Weaver, R. B. Atkinson

Department of Organismal and Environmental Biology, Christopher Newport University

julie.m.slater@gmail.com, abigail.weaver.14@cnu.edu, atkinson@cnu.edu

Abstract

The Great Dismal Swamp National Wildlife Refuge (GDSNWR) and Alligator River National Wildlife Refuge (ARNWR) are less than 60 miles (96 km) apart and contained extensive stands of Atlantic white cedar [Chamaecyparis thyoides (L.) B.S.P.]. Two reference stands were selected with divergent hydrologic regimes based on 18 shallow wells; the ARNWR stand exhibited persistent saturation, and water levels in the GDSNWR stand were 60 cm below the surface for much of the growing season. In each reference stand, ring width at DBH was sampled for 54 trees. In 11 stands at GDSNWR for which hydrologic characterization is lacking, a total of 105 trees were analyzed to compare growth patterns to reference AWC. In addition to using classic detrending statistics to remove age-related growth trends, we calculated annual increase in basal area increment (BAI) to account for the fact that small rings on large trees may represent more growth than wide rings on smaller trees. BAI calculations revealed that at 50 years of age, mean basal area of AWC trees at GDSNWR (462.6 cm2) was >400% greater than trees at ARNWR (118.76 cm2). Using the reference sites, we successfully placed 11 AWC stands on a hydrologic continuum between the two reference stands.

Keywords: Dendroecology, basal area increment, water table, reconstructed hydrology.

Biography: Julie Slater works for Dr. Rob Atkinson's lab at Christopher Newport University in Newport News, VA. She will be presenting the results of their tree ring analysis of Atlantic white cedar in VA and NC, and their implications for hydrologic restoration. Julie will be continuing her education this fall at Ohio State where she will pursue an MS in environment and natural resources under Dr. Matt Davies.