ECOLOGICAL SYSTEMS OF THE SOUTH TEXAS COAST.

We mapped 22 soil ecogroups and 66 ecological mapping systems (EMSs), essentially current vegetation, for eight coastal counties in South Texas, from Refugio and Aransas County south to the Mexican border. We used supervised classification to extract land cover from 10-m resolution Sentinel-2 satellite imagery. We accessed Lidar point cloud information to derive vegetation height and then use it to distinguish among herbaceous, shrubland, and woodland-forest EMS types. We derived elevation and potential ponding information from Lidar. We created image objects (uniform polygons), from Sentinel-2 data, and attributed land cover, soil ecogroup, vegetation height, elevation, and ponding potential to the objects. We used those attributes of image objects to model EMS types. We completed heads-up modification of both land cover and EMS modeling results by using aerial photograph interpretation to improve results. The agreement between EMS-mapped type and 643 field-collected plots was >75%. The most abundant EMS types included Coastal and Sandsheet: Deep Sand Grassland (10.7% of the region); Native Invasive: Mesquite-Mixed Shrubland (5.0%); Gulf Coast: Coastal Prairie (4.6%); and South Texas: Sandy Mesquite Savanna Grassland (4.4%). The EMS results are nine times better resolution than currently available maps, and use of height to identify EMS type by distinguishing among herbaceous, shrubland, and woodland types enhanced mapping beyond what has been previously accomplished. The new EMS dataset will facilitate analysis of the distribution of habitats and modeling of species of conservation concern that are tied to EMS types or vegetation landscape patterns. Finer resolution EMS type maps can be combined with improved soil ecogroup maps to facilitate better identification of appropriate vegetation management and restoration options at resolutions that are useful to land managers. [ABSTRACT FROM AUTHOR]