Validation of the MODIS LAI Product in Coniferous Forest of Ruokolahti, Finland
نویسندگان
چکیده
Leaf area index collected in a needle-leaf forest site near Ruokolahti, Finland, during a field campaign in June 14-21, 2000, was used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) LAI and FPAR algorithm. The field LAI data was first related to 30m resolution Enhanced Thermal Mapper Plus (ETM+) images using empirical methods to create a high resolution LAI map. It shows that comparisons at patch level are more reliable than the pixel level. Comparison of the aggregated high resolution LAI map and corresponding MODIS LAI retrievals imbues confidence in the MODIS LAI and FPAR algorithm. However, the MODIS algorithm, adjusted to high resolution, generally overestimates the LAI due to the influence of the understory vegetation, indicates the need for improvements in the algorithm. An improved correlation between field measurements and the Reduced Simple Ratio (RSR) suggests that the shortwave infrared (SWIR) band may provide valuable information for needle-leaf forests.
منابع مشابه
Evaluation of the MODIS LAI algorithm at a coniferous forest site in Finland
Leaf area index (LAI) collected in a needle-leaf forest site near Ruokolahti, Finland, during a field campaign in June 14–21, 2000, was used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) LAI algorithm. The field LAI data was first related to 30-m resolution Enhanced Thermal Mapper Plus (ETM+) images using empirical methods to create a high-resolution LAI map. The analysis of...
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