Tiekel Watershed 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 Tiekel River Watershed. One Landsat TM satellite scene (Path 66, Row 17 acquired August 25, 1987) was used to classify the project area into 23 earth cover categories. An unsupervised clustering or seeding technique was used to determine the location of field sites and a custom field data collection card 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 324 field sites during an 8-day field season from July 7, 1998 through July 14, 1998. Approximately 45% (144) 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 major categories was 80%. The cooperators in this project were the Bureau of Land Management-Alaska, and Ducks Unlimited, Inc.