The contribution of C3 and C4 grasses to interannual variability in time-integrated NDVI over the U.S. Great Plains

C. Ricotta; Bradley C. Reed; Larry L. Tieszen

doi:10.1142/9789812777249_0043

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The contribution of C3 and C4 grasses to interannual variability in time-integrated NDVI over the U.S. Great Plains

C. Ricotta·Bradley C. Reed·Larry L. Tieszen

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Abstract

Time integrated normalized difference vegetation index (ΣNDVI) derived from NOAA AVHRR multitemporal imagery over a 10-yr period (1989-1998) was used as a surrogate for primary production to investigate the impact of interannual climate variability on grassland performance for central and northern U.S. Great Plains. First, the contribution of C 3 and C 4 species abundances to the major grassland ecosystems of the U.S. Great Plains is described. Next, the relation between mean ΣNDVI and the ΣNDVI coefficient of variation (CV ΣNDVI) used as a proxi for interannual climate variability is analyzed. Results suggest that the differences in the long-term climatic control over ecosystem performance approximately coincide with changes between C 3 - and C 4 -dominant grassland classes. Variation in remotely sensed net primary production over time is higher for the southern and western plains grasslands (primarily C4 grasslands), whereas the C 3 -dominated classes in the northern and eastern portion of the U.S. Great Plains generally show lower CV ΣNDVI values.

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Source-reported bounding extent: 38.788345355085625° to 48.69096039092549° latitude; -109.599609375° to -95.0537109375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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C. Ricotta, Bradley C. Reed, Larry L. Tieszen. 2011-11-21. The contribution of C3 and C4 grasses to interannual variability in time-integrated NDVI over the U.S. Great Plains. https://doi.org/10.1142/9789812777249_0043

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