EVALUATING MAPS OF DEPRESSIONAL WETLANDS ON THE DOUGHERTY PLAIN USING LANDSAT 8 GENERATED NDWI

The Dougherty Plain physiographic province is a karstic landscape characterized by deep sands, vuggy limestone bedrock, frequent sinkholes, abundant clusters of depressional wetlands, and deeply incised streams. Depressional wetlands on this landscape can be challenging to map due to their small size and dynamic hydrology. The overarching goal of our research is to evaluate existing wetland map products available for the Dougherty Plain using NDWI. Our objectives were to 1) map wetlands using approximately 6 years (2013-2019) of Landsat 8 generated NDWI images; and 2) evaluate potential wetland depressions identified through NDWI peak intensities with known wetland locations. A tool previously created for mapping episodic flows with NDWI was adapted for mapping wetted depressions. Our preliminary findings indicate that peak intensities at known wetland locations were easily identified on approximately 65% of images. Next steps include evaluation of peak intensities within wetlands mapped by Martin et al. 2012 and the National Wetland Inventory at our local pilot scale and throughout the Dougherty Plain.