In large river ecosystems, the timing, extent, duration and frequency of
floodplain inundation greatly affect the quality of fish and wildlife
habitat and the supply of important ecosystem goods and services.
Seasonal high flows provide connectivity from the river to the
floodplain, and seasonal inundation of the floodplain governs ecosystem
structure and function. River regulation and other forms of hydrologic
alteration have altered the connectivity of many rivers with their
adjacent floodplain – impacting the function of wetlands on the
floodplain and in turn, impacting the mainstem river function.
Conservation and management of remaining floodplain resources can be
improved through a better understanding of the spatial extent and
frequency of inundation at scales that are relevant to the species
and/or ecological processes of interest. Spatial data products
describing dynamic aspects floodplain inundation are, however, not
widely available. This study used Landsat imagery to generate multiple
observations of inundation extent under varying hydrologic conditions to
estimate inundation frequency. Inundation extent was estimated for 50
Landsat scenes and 1334 total images within the Gulf Coastal Plains and
Ozarks Landscape Conservation Cooperative (GCPO LCC), a conservation
science partnership working in a 730 000-km 2 region in the south
central USA. These data were composited into a landscape mosaic to
depict relative inundation frequency over the entire GCPO LCC. An
analytical methodology is presented in the related publication for
linking the observed inundation extent and frequency with long-term gage
measurements so that the outcomes may be useful in defining meaningful
critical thresholds for a variety of floodplain dependent organisms as
well as important ecological processes
The GCPO Inundation
Frequency (IF) mosaic is a cartographic product is intended to provide a
landscape scale comparison of floodplain inundation frequency. For a
more detailed analysis, please refer to the IF data for an individual
Landsat scene (path/row), and the excel file listing the dates of
imagery used to construct IF for that scene (Available at
https://www.sciencebase.gov/catalog/item/5617e3c3e4b0cdb063e3fc35).
Methodology and potential application details are in: Allen, Y. (2016) Landscape Scale Assessment of Floodplain Inundation Frequency Using Landsat Imagery. River Res. Applic., 32: 1609–1620. doi: 10.1002/rra.2987.
https://onlinelibrary.wiley.com/doi/full/10.1002/rra.2987