Document: SEB-3-35-24

Seasonal variations in LAI, NDVI, and biomass on four tundra vegetation types at Ivotuk, Alaska.

RIEDEL, S.M.* ¹, H.E.EPSTEIN ¹, D.A.WALKER ², D.L.RICHARDSON ¹ and M.P.CALEF ¹

University of Virginia, Charlottesville, Virginia 22903 USA ¹
University of Alaska Fairbanks, Fairbanks, Alaska 99775 USA ²

Abstract:
Substrate and topography are considered factors that control local heterogeneity of tundra vegetation. Intraseasonal trends of leaf area index (LAI), normalized difference vegetation index (NDVI), and biomass were investigated for four distinct tundra vegetation types at Ivotuk, Alaska. The study site, located on the north slope of the Brooks Range (68.49 N, 155.74 W), is characterized by a growing season length of 136-150 days and a mean July maximum temperature of 12 C. LAI, NDVI, and biomass samples were collected bi-weekly from four 100 m x 100 m grids, each representing a different vegetation type, during the 1999 growing season. The vegetation types examined in this study included Moist Acidic Tundra (MAT), Moist Non-acidic Tundra (MNT), Moss Tundra (MT), and Shrub Tundra (ST). Peak biomass was significantly different among the four vegetation types. NDVI was significantly related to LAI for the composite of all tundra vegetation types. Values of LAI, NDVI, and biomass obtained from this field study are used in conjunction with satellite data for the purpose of examining responses to climate change.

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This abstract is being presented at: 10:30 AM in session:
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