부산대학교 도서관

The aim of this study is to understand which vegetation indices represent good proxies for gross primary productivity (GPP) and whether they are able to capture the effect of drought on GPP in a temperate dry heathland ecosystem. To this end, a meteorological tower was equipped with both eddy covariance instrumentation to measure CO2 fluxes as well as with an optical sensor to calculate several greenness and chlorophyll-sensitive indices (e.g. Terrestrial Chlorophyll Index (TCI), Inverted Red-Edge Chlorophyll Index (IRECI)) as proxies of GPP. Results showed that the vegetation indices well capture the variability in GPP, except during drought. Incorporating soil moisture, however, substantially improved GPP estimation by the vegetation indices. These results reveal that vegetation indices are able to capture variation in GPP, even during extreme drought, providing that soil moisture is properly accounted for.