THE ALASKA 4-PHASE FOREST INVENTORY SAMPLING DESIGN USING REMOTE-SENSING AND GROUND SAMPLING

A four-phase sampling method using Landsat, high-altitude color infrar ed photography low-altitude color infrared photography, and ground sam ples was tested in interior and coastal Alaska from 1982 through 1986. Ratio and regression estimators were applied using variables at the r emote sensing phases as covariates related to variables of interest me asured on the ground. The four-phase sampling strategy yielded more ef ficient estimators in coastal Alaska's more heavily timbered area than in interior Alaska's highly heterogeneous vegetation complexes. Advan tages and disadvantages associated with each of she phases of the stud y are presented, as well as a general evaluation of the entire system.