Angiosperm Production of Three Virginia Marshes in Various Salinity and Soil Nutrient Regimes

Abstract

The net aerial angiosperm productivity, salinity, and soil nutrient composition of three Virginia marshes were determined. Oligohaline Ware Creek Marsh and mesohaline Carter Creek Marsh were most productive, 563 and 572 g m−2yr−1, respectively, while euhaline Wachapreague Marsh was least productive, 362 g m−2yr−1. Species in Carter and Ware Creek Marshes were clustered into associations based on salinity tolerance. Nitrogen and phosphorus concentrations ofSpartina alterniflora tissue were high in the spring and decreased as the growing season continued. Soil nutrient concentrations were variable, and trends during the growing season were not discernible. No significant correlations were found between soil and plant nutrient concentrations. Although the empirical data suggests that high soil salinity and low soil nitrogen and phosphorus concentrations limited primary productivity in Wachapreague Marsh, a multiple regression of standing crop on these parameters did not delineate any as the primary factors limiting salt marsh production.