%0 Research article
%T Updating stand level inventory data applying growth models and visual interpretation of aerial photographs
%A Anttila, Perttu
%D 2002
%J Silva Fennica
%V 36
%N 2
%R doi:10.14214/sf.544
%U https://silvafennica.fi/article/544
%X In this study two procedures for updating stand level inventory data  were developed and tested. The development of the growing stock of 62  stands over 12 years was simulated in the MELA stand simulator with no  prior information of rapid changes, such as clear-cuttings. The  acceptability of the simulation was decided standwise with visual  interpretation of aerial false-colour photographs. If the simulated data  were not accepted, new stand attributes were assessed with photo  interpretation in procedure 1. In procedure 2, on the other hand, it was  possible to utilise old management proposals. In case a cutting or  other operation had been proposed and it looked like the operation had  been realised, the interpreters accepted the proposal. Otherwise the  last implemented operation and implementation year were interpreted. In  case no operation had been carried out during the updating period but  the growth model updated data were not acceptable, the same stand  characteristics were estimated as in procedure 1. Stands where a  proposal had been accepted or an operation interpreted were later  updated again in MELA so that the program simulated the operations. The  Root Mean Squared Errors of stem volume were 62 and 57 m3 per ha (34 and  30%) with procedures 1 and 2. With procedure 2 the accuracy of updating  was comparable with a stand level field inventory carried out in the  study area. The productivity of the photo interpretation procedures was  57 and 84 ha per h, respectively, whereas the productivity of a field  inventory has been 3.3–5 ha per h.