Evaluating Physiological and Growth Responses of Arundinaria Species to Inundation


Mary Catherine Mills

Additional Authors:

Brian S. Baldwin, Gary N. Ervin


December 2011


ABSTRACT Dense stands of Arundinaria species, or canebrakes, once were a dominant landscape feature along floodplains of the southeastern United States. However, human activities have reduced canebrakes to fragmented remnants representing ,2% of their extent prior to European settlement. Canebrake restoration thus is a top priority for preserving and improving wetland biodiversity in the United States. Successful restoration requires an understanding of factors influencing establishment of the two most common United States Arundinaria species; therefore, this greenhouse study examined effects of inundation on A. gigantea and A. tecta. Both Arundinaria species were subjected to 0, 2, 4, or 6 weeks of inundation under long-day, warm temperature growing season conditions. Plant growth, mean net photosynthesis (Pn), and stomatal conductance (Gs) were measured on a weekly basis, and at the conclusion of the experiment, above- and belowground biomass were measured. We found significant correlations of Pn and Gs with duration of flooding and duration of post-inundation recovery, as well as a significant interaction among time, species, and flood duration, with both species responding similarly to flooded conditions. Once flooding was arrested, both Pn and Gs rates were higher in A. tecta than A. gigantea; the same was true for growth rates across the duration of the study. In conclusion, A. tecta appeared to be more flood tolerant than A. gigantea, reflecting habitats in which these species are known to occur. Future canebrake restoration projects may benefit from this information on differential flooding tolerance in selecting restoration sites or restoration species, based on hydrologic conditions.