The LiDAR variables chosen must capture the variability of the stand parameter being surveyed, which in turn is influenced by local topography, soils and silvicultural history.
The parameters in the model were estimated using the SAS MIXED procedure, with local stand parameter L i treated as a normally distributed random term varying between stand with variance ( {sigma}_{s tan d}^2 ), a tree effect T ij treated as a normally distributed random term with variance ( {sigma}_{treeleft(s tan dright)}^2 ), and a within-tree error term e ijk with variance ( {sigma}_e^2 ).
We assume that the data availability is not correlated to the value of major site and stand parameters, thus the samples suffice to estimate the distribution of these site and stand parameters.
Furthermore, among the stand parameters, inter-tree distance in the slope direction has the greatest influence on the slope's safety factor.
A preliminary analysis is performed to assess the impact of different stand parameters and root morphologies on the slope's safety factor as well as on the volume of soil mobilized by a landslide.
The stand parameters included in the model can probably be extracted from national forest inventories in many countries and understood without specialist taxonomic knowledge, making the model applicable in practice to support forest management decision-making on enhancing forest biodiversity at stand level.
Quantitatively the differences between estimates of stand parameters are not statistically significant (except for BA - this result was also found in Hudak et al. [52] and they postulate that this bias is a result of the natural logarithm transformations and back transformations).
The current upgrading of the FORDATA database by the FRMP is a move in this direction and stand parameters for forest plantation sub-blocks can be retrieved from FORDATA for use in managerial decisions.
Leaf area in relation to stand parameters, e.g., ground area potentially available (APA), which could be named as individual tree leaf area index, but also leaf area in relation to stemwood increment which is described as growth efficiency (Waring, 1983) are important research issues.
Quantitatively the differences between estimates of stand parameters are not statistically significant (except for BA - this result was also found in Hudak et al. [ 52] and they postulate that this bias is a result of the natural logarithm transformations and back transformations).
