Elemental Composition of Utricularia‐Periphyton Ecosystems from Okefenokee Swamp

The elemental composition (% dry mass), production (grams per square metre per year), mass (grams per square metre), and environmental variables of Utricularia—periphyton ecosystems form Okefenokee Swamp were measured each month for a year. These ecosystems were found to be most productive in the spring and fall and least productive in the summer when water levels were low. Concentrations and standing stocks of tissue ash, P, N, K, Na, Ca, Mg, Fe, Al, and Mn were correlated with various environmental parameters: temperature, dissolved O2, K, Na, Ca, Mg, pH, and water depth. Standing stocks of elements wee, in general, more correlated with environmental parameters than were concentrations (% dry mass). Phases plane diagrams were used to demonstrate that elemental concentrations and production in the ecosystems followed well—defined cycles that were related to environmental fluctuations.