Influence of Disturbance on Plant Community Structure and Biological Invasion in the Riparian Zone of the Mobile-Tensaw Delta.

摘要

McPherson, Brian, M. S., University of South Alabama, July 2017. Influence of disturbance on plant community structure and biological invasion in the riparian zone of the Mobile-Tensaw Delta. Chair of Committee: Kelly M. Major, Ph.D. Although the East Gulf Coastal Plain is recognized for its high degree of endemism, relatively little is known about the environmental circumstances and ecological processes that promote long-term maintenance of diversity and ecosystem integrity in this region. The research described herein was designed to investigate plant distributional patterns in the Mobile-Tensaw Delta (i.e., a region of Alabama characterized by unique habitat types, a high number of endemic species, as well as high species diversity). Sampling plots were established along geographic gradients to assess the influence(s) of seasonal and annual environmental variation and invasion on plant communities residing in the transition zone between aquatic and terrestrial habitats. Vegetation surveys resulted in the documentation of 145 plant species from 81 families, 11 of which have achieved invasive status. Moreover, combined statistical analyses of abiotic and biotic data suggest that environmental variability in salinity, moisture, and sediment organic content, as well as habitat type are plausible drivers of plant community structure in the Mobile-Tensaw Delta.