Summary

Description

Accuracy assessments of two versions of Landsatassisted land cover maps were conducted on the coastal plain of the Arctic National Wildlife Refuge. Ground determinations and map classifications were compared for 126 map polygons. Agreement occurred at 53 of the polygons on the 1982 Landsat map and 48 on the 1985 map. The largest source of error 25 on the 1982 map and 27 on the 1985 map was cutpoints between closely related land cover classes. Classes are related to each other along gradients of moisture, shrub cover, or total plant cover. Misclassification errors where the plant community found on the ground clearly did not belong to the map class occurred at 17 of the 1982 map polygons and 22 of the 1985 polygons. Most commonly the map misclassified braided river floodplain communities as wet or moist plant communities. Description errors indicating that the land cover class description needed additions or modifications to allow the user to accurately identify the class occurred on 6 of the 1982 polygons and 4 of the 1985 polygons. Since cutpoint errors between closely related classes accounted for the majority of errors, the Landsatassisted maps are useful for showing general distributions of land cover classes.