Delineation of marsh types and marsh type-change in Coastal Louisiana for 2007 and 2013

The Bureau of Ocean Energy Management (BOEM) researchers often require detailed information regarding emergent marsh vegetation types (i.e., fresh, intermediate, brackish, and saline) for modeling habitat capacities and mitigation. In response, the U.S. Geological Survey, in collaboration with the Bureau of Ocean Energy Management produced a detailed change classification of emergent marsh vegetation types in coastal Louisiana from 2007 and 2013. This study incorporates decision-tree analyses to classify emergent marsh vegetation types using two existing vegetation surveys and independent variables such as Landsat and high-resolution airborne imagery from 2007 and 2013, bare-earth digital elevation models based on airborne light detection and ranging (lidar), alternative contemporary land cover classifications, and other spatially explicit variables. Image objects were created from 2007 and 2013 National Agriculture Imagery Program (NAIP) color-infrared aerial photography. The final classification consists of three 10-m raster datasets that were produced by using a majority filter to classify image objects according to the marsh vegetation type covering the majority of each image object. The classifications are dated 2007 and 2013 because the dates of the two vegetation surveys and of the high-resolution airborne imagery that was used to develop image objects. The seamless classification produced through this work can be used to help develop and refine conservation efforts for priority natural resources.