LITTER NUTRIENT CONTENT AND PRODUCTION IN THE GREAT DISMAL SWAMP

Litter production was studied in the Great Dismal Swamp, Virginia in four plant communities which differ primarily in species composition and flooding regime. Greatest leaf deposition occured in the more flooded communities, maple-gum (Acer-Nyssa) with 536 gm^-2 yr^-1 and cypress (Taxodium distichum (L.) Richard) with 528 gm^-2 yr^-1, followed by the cedar (Chamaecyparis thyoides (L.) BSP) and mixed hardwood (Quercus-Acer-Nyssa-Liquidambar) communities, with 506 gm^-2 yr^-1 and 455 gm^-2 yr^-1, respectively. Apparently periodic flooding promotes production. Peaks occurring in October and November corresponded to autumn leaf fall, while peaks in January and May were due to some leaf litter combined with a large amount of woody litter. Litter nutrient concentrations were higher, except for Ca, in the most abundant species (cypress and water gum) in the frequently flooded cypress community. Higher leaf fall rates and litter nutrient concentrations resulted in greater nutrient deposition in the cypress and maple-gum communities.