2021 ESA Annual Meeting (August 2 - 6)

Plant communities differ between restored, remnant, and developed riparian areas along an urban river

On Demand
Alexandrea M. Peake, Biology, University of Michigan-Flint;
Background/Question/Methods

Riparian areas in urban environments often have varying levels of transformation and development due to anthropogenic changes and construction. One river’s riparian areas may vary from completely lined with cement and dammed, to being left undisturbed. For riparian areas that have been developed, there has been increasing awareness for the benefits of riparian restoration. However, restoration often has varying goals. In many restored riparian areas, the new or current plant community is very different from the historical plant community. Even in remnant riparian areas the current plant community may be different from the historical plant community due to anthropogenic changes and influence. This could potentially impact insect communities, particularly if vegetative structure is changed or if the flowering forb community is changed. We studied the 2 km stretch of the Flint River that runs through Flint, Michigan, to determine how the plant communities of the restored riparian areas, remnant riparian areas, and developed riparian areas differ from each other. Specifically, we investigated blooming plant abundance and diversity, plant community structure, and proportional groundcover within replicated transects of 8, 1-ha plots. We hypothesized that blooming plants would be more abundant and diverse in areas where the riparian was restored, plant community structure and proportional ground cover would differ between restored, remnant, and developed sites.

Results/Conclusions

We determined that while heavily urbanized and intensively managed lawn does include flowering forbs, restored areas contain the greatest proportion of forbs compared to other regions. Remnant riparian areas had more tree cover than any other zone, and differ in plant community composition from riparian restoration zones along the riverfront. Our findings indicate that habitat management in urban greenspaces create diverse plant communities of native plants that may not match remnant communities, but still may provide key ecosystem services (e.g., pollinator support) while matching habitat preferences and aesthetic goals.