Covariance of greenness and terrain variables over the Konza PrairieAn analysis is made of time-dependent covariance of the greenness vegetation index with mapped terrain variables over the Konza Prarie (Kansas) during the 1987 growing season. The analysis was part of an ongoing project to establish appopriate ground-sampling and data-integration strategies for satellite-based monitoring of land surface climate conditions. Greenness images for six dates between May and October were derived from atmospherically corrected thematic mapper (TM) data and coregistered with maps of woody vegetation, fire, and soils. Local variance in greenness peaked in mid-June, falling rapidly until mid-August, and declining gradually thereafter. Greenness images exhibited positive autocorrelation up to distances of 180-210 m, but the dominant scale of pattern occurred at a block size of 60 m by 60 m throughout the growing season. 40-44 percent of total scene variance in July and August was accounted for by the effects of woody vegetation (8.9 percent of the area), prairie burning, and soil type. The effect of these terrain variables was fairly consistent between June and late August and was manifested as additional high-frequency spatial variation in imagery from that period.
Document ID
19910031117
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Davis, Frank W. (California Univ. Santa Barbara, CA, United States)
Dubayah, Ralph (California Univ. Santa Barbara, CA, United States)
Dozier, Jeff (California, University Santa Barbara, United States)
Hall, Forrest G. (NASA Goddard Space Flight Center Greenbelt, MD, United States)