Document: JEF-3-40-27

A comparison of aboveground structure and litter production of Atlantic white cedar swamps in northeastern North Carolina.

DEBERRY, J.W.*, R.T.BELCHER, D.T.LOOMIS and R.B.ATKINSON

Christopher Newport University, Newport News, Virginia ¹

Abstract:
Structural and functional attributes including aboveground biomass, basal area, species composition, stem density, litter production and hydrology were measured in naturally regenerated Chamaecyparis thyoides (L.)B.S.P. stands in Great Dismal Swamp (GDSNWR) and Alligator River National Wildlife Refuges (ARNWR). Two stands were selected at each refuge representing mature (6070) and intermediate (1535) age classes. Total aboveground biomass for mature stands was 234,447 225,392 kg/ha and among intermediate sites 131,989 113,252 kg/ha. Although total biomass was similar within each age class, other aspects of structure differed. Chamaecyparis thyoides was the dominant tree species contributing greater than 58% relative basal area in all stands; however, Acer rubrum dominated GDSNWR intermediate in terms of relative biomass (56%). Live tree density was greater (P<0.01) for ARNWR sites, particularly in ARNWR intermediate (39,722 stems/ha) which was 14 times greater than GDSNWR intermediate. Annual litterfall productivity exhibited a similar trend: ARNWR mature (526 g/m²) and intermediate (379 g/m²) productivity was higher than GDSNWR mature (324 g/m²) and intermediate (251 g/m²) respectively. Furthermore, both ARNWR sites were considerably wetter (P<0.001) than GDSNWR sites, based upon eleven months of twice daily depth to water table readings. Hydrologic differences among GDSNWR and ARNWR may explain species composition and vegetation differences. However, productivity results suggest that other environmental variables may be influencing these stands.

Keywords: Chamaecyparis thyoides, aboveground biomass, hydrology, productivity

This abstract is being presented at: 2:15 PM in session:
Oral Session #16: Plant Demography: Trees and Shrubs.