5 CONCLUSION
Both the proportion of coniferous and deciduous trees and stand
heights can be estimated with high accuracy compared to ground
reference data. Better models for the area proportions may yield
better results; the equations shown above may lead to negative
area proportions or above 100 % for extreme penetration rates.
The empirical stand height models need to be further checked for
their robustness on other data. A theoretical model needs to be
developed, although the 90 percentile is a reasonable variable as
such.
6 ACKNOWLEDGEMENTS
The research has been funded by the Austrian national science
foundation (FWF) through the project P12812-INF.
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Internatioi
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