Galena Military Operations Area/Nowitna National Wildlife Refuge Earth Cover Classification

The Bureau of Land Management (BLM) - Alaska and Ducks Unlimited, Inc. (DU) have been cooperatively mapping wetlands and associated uplands in Alaska using remote sensing and GIS technologies since 1988. The goal of this project was to continue the mapping effort by mapping the Galena Military Operations Area (MOA), Nowitna National Wildlife Refuge (NWR), and associated uplands. Portions of three Landsat TM satellite scenes (Path 73, Rows 14, 15, and 16 acquired 07/02/99) were used to classify the project area into 30 earth cover categories. An unsupervised clustering technique was used to determine the location of field sites and a custom field data collection form and digital database were used to record field information. A helicopter was utilized to gain access to field sites throughout the project area. Global positioning system (GPS) technology was used both to navigate to pre-selected sites and record locations of new sites selected in the field. Data were collected from 575 field sites during a 12- day field season from 6/26/00 through 7 /7 /00. Approximately 30% ( 172) of these field sites were set aside for accuracy assessment. A modified supervised/unsupervised classification technique was performed to classify the satellite imagery. The classification scheme for the earth cover inventory was based on Viereck et al. (1992) and revised through a series of meetings coordinated by the I3LM - Alaska and DU. The overall accuracy of the mapping categories was 87.2% at the +/-5% level of variation in interpretation of the accuracy assessment reference site.