Upper Midwest Environmental Sciences Center
The Upper Mississippi River floodscape: spatial patterns of flood inundation and associated plant community distributions
De Jager, N. R., J. J Rohweder,., Y. Yin, and E. Hoy. 2015. The Upper Mississippi River floodscape: spatial patterns of flood inundation and associated plant community distributions. Applied Vegetation Science. doi: 10.1111/avsc.12189
Question: How is the distribution of different plant communities associated with patterns of flood inundation across a large floodplain landscape?
Location: Thirty-eight thousand nine hundred and seventy hectare of floodplain, spanning 320 km of the Upper Mississippi River (UMR).
Methods: High-resolution elevation data (Lidar) and 30 yr of daily river stage data were integrated to produce a ‘floodscape’ map of growing season flood inundation duration. The distributions of 16 different remotely sensed plant communities were quantified along the gradient of flood duration.
Results: Models fitted to the cumulative frequency of occurrence of different vegetation types as a function of flood duration showed that most types exist along a continuum of flood-related occurrence. The diversity of community types was greatest at high elevations (0–10 d of flooding), where both upland and lowland community types were found, as well as at very low elevations (70–180 d of flooding), where a variety of lowland herbaceous communities were found. Intermediate elevations (20–60 d of flooding) tended to be dominated by floodplain forest and had the lowest diversity of community types.
Conclusions: Although variation in flood inundation is often considered to be the main driver of spatial patterns in floodplain plant communities, few studies have quantified flood–vegetation relationships at broad scales. Our results can be used to identify targets for restoration of historical hydrological regimes or better anticipate hydro-ecological effects of climate change at broad scales.
Bottomland hardwood forest; Climate change; Disturbance; Diversity; Floodscape; Restoration; Wetland