EMPIRICAL RELATIONSHIPS BETWEEN STRUCTURAL AND SPECTRAL FACTORS OF YELLOWSTONE LODGEPOLE PINE FORESTS

Multiple regression analysis was used to examine the relationships bet ween spectral and biotic factors within the lodgepole pine (Pinus cont orta var. latifolia) forests of Yellowstone National Park. Field-sampl ed data on forest overstory and understory conditions were regressed a gainst Landsat Thematic Mapper (TM) radiance values and transformed TM data for 70 stands. Factors relating to the physical structure of the forest canopy (height, basal area, biomass, and leaf area index (LAI) ) are best predicted using a combination of visible and middle-infrare d Thematic Mapper bands. Other overstory factors (density, size divers ity, mean diameter, and number of overstory species) were not well exp lained by the TM data or by combinations of TM data with transformed s pectral data. Understory factors (number of seedlings; number of under story species; total cover by forbs, grasses and shrubs; and total liv ing and nonliving cover) were poorly explained by regression models in corporating spectral and transformed spectral data.