  Large-scale forest resource maps based on national forest inventory (NFI)
data and airborne laser scanning may facilitate synergies between NFIs and
forest management inventories (FMIs). A comparison of models used in such a
NFI-based map and a FMI indicate that NFI-based maps can directly be used in
FMIs to estimate timber volume of mature spruce forests. Traditionally, FMIs
and NFIs have been separate activities. The increasing availability of detailed
NFI-based forest resource maps provides the possibility to eliminate or reduce
the need of field sample plot measurements in FMIs if their accuracy is
similar. We aim to 1) compare a timber volume model used in a NFI-based map and
models used in a FMI, and 2) evaluate utilizing additional local sample plots
in the model of the NFI-based map. Accuracies of timber volume estimates using
models from an existing NFI-based map and a FMI were compared at plot and stand
level. Estimates from the NFI-based map were similar to or more accurate than
the FMI. The addition of local plots to the modeling data did not clearly
improve the model of the NFI-based map.The comparison indicates that NFI-based
maps can directly be used in FMIs for timber volume estimation in mature spruce
stands, leading to potentially large cost savings.
