Temporal studies of deciduous forests in northeastern Kansas using landsat thematic mapper images.

Abstract

Eight years of Landsat Thematic Mapper (TM) data were used to assess vegetation changes in two temperate deciduous forests located on the Fort Leavenworth Military Reservation in northeastern Kansas, U.S.A. The primary forests are an upland oak-hickory hardwood forest and a floodplain cottonwood-sycamore forest. Normalized Difference Vegetation Index (NDVI) and the ratio ofTM band 5 to band 4 (moisture stress index) were used to detect changes in health and vigor of the forests. NDVI data indicate a one-to two-year lag in the full response of the forests to changes in precipitation during the drought years from 1987 to 1989. The forests also display different responses at the start of the drought, with the cottonwood forest experiencing increased NDVI and the hardwood forest experiencing a decline.