Science » Aerial photography and remote sensing
The figure to the right shows an example of a true color and false color infrared aerial photograph from the Nisqually Delta prior to the restoration of tidal flow and dike removal on the Nisqually National Wildlife Refuge.
Aerial photographs shot at low tide when mudflats and channels are at maximum exposure are valuable tools for visual documentation of water drainage off the landscape and geomorphic change. We will take aerial photographs during the vegetative growing season. Color infrared (IR) aerial photographs will be georeferenced to UTM NAD 83 (ArcGIS, ESRI) using registered targets or landmarks. Color IR is better suited to distinguish vegetation signals from mud and bare ground than true color aerial photography. We will classify color infrared pixels into land cover classifications (such as water, mudflat, wetland vegetation, upland vegetation, and bare ground) using GIS (ERDAS Imagine Software, Leica Geosystems) and analyze the percent cover of each category. This remote sensing tool is valuable in tracking vegetation colonization over a large area over time. Vegetation colonization will be supplemented with on-the-ground vegetation surveys.