The relationship between Phalaris arundinacea and Glyceria grandis and their epiphyte communities in the Maple River.

Abstract

The relationship between epiphytes and their aquatic hosts has scarcely been studied for freshwater ecosystems. The epiphytes gain substrate on which to live from the plants but how do they affect the plants? Understanding this relationship is of importance to understand the diversity of macrophytes in streams. If the epiphytes benefit their macrophytic hosts, then significantly decrease growth should be observed for the plants scrubbed of their epiphytes when compared to the controls. Here the effect was examined in two sites similar in physical characteristics in the Maple River, Northern Lower Michigan. Phalaris arundinacea and Glyceria gradis were the organisms chosen for study due to their abundance and accessibility. Epiphytes were scrubbed from the treated group three times a week for two weeks, during which time the heights and leave numbers were recorded. In the end a t-test was preformed to look for a significant difference in growth between the control groups and the treated groups. No significance was found for the over all change in growth and leaf number of the plants leaving the hypothesis neither supported nor refuted. This was probably due to the brevity of the study and because it was preformed towards the end of the growing season. It is suggested that future studies run longer trials during spring, the height of the growing season.