Effects of drainage and soil organic content on growth of Spartina alterniflora (Poaceae) in an artificial salt marsh mesocosm

An artificial salt marsh mesocosm was constructed using 680-L polypropylene tanks to determine the effect of soil drainage depth and organic content o n growth and rhizome proliferation of the salt marsh smooth cordgrass Spart ina alterniflora. Soil drainage depth had no effect on accumulation of aeri al or subsurface plant tissue, but tanks that had 2.5% soil organic content supported enhanced aerial tissue and rhizome growth compared to tanks that contained sand alone. We propose a mathematical model for predicting the m ass of photosynthetically significant leaf tissue without cutting and dryin g leaves. Implications of these findings for salt marsh creation projects a re discussed.