Susitna Military Operations Area 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 Susitna Military Operations Area (MOA) and associated uplands. Portions of three Landsat TM satellite scenes (Path 70, Rows 16 and 17 acquired 08/16/00 and Path 69, Row 17 acquired 07/10/89) were used to classify the project area into 44 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 on 343 field sites during a 12-day field season from 7/15/99 through 7/26/99 and 421 field sites during an II-day field season from 8/01/99 through 8/11/99. Of the total sites visited, only 679 sites were actually utilized as either image classification training sites or accuracy assessment sites. A total of 514 sites were used as training sites while approximately 25% (165) 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 BLM -Alaska and DU. The overall accuracy of the mapping categories was 87.6% at the +/-5% level of variation in interpretation of the accuracy assessment reference sites.