Chapters 1 and 2 represent simple distribution modeling while Chapters 3 and 4 compares the results of simple and mixture distribution modeling. Chapter 1 shows suitable distribution model selection for forest diameter structure modeling in case of a pure larch forest stand. Chapter 2 shows also distribution model selection, but for both diameter and height structures in case of pure pine forest stands. Rather than distribution model selection, Chapter 3 shows a comparison of simple and mixture distribution modeling in structural parameters, both diameter and height in case of spruce-larch mixed forest. Chapter 4 shows flexible mixture distribution modeling in case of larch forest stands and further diameter-height relationships discovered for volume estimation. In chapter 5, we are concentrated on one of the important tasks of quantifying forests AGB. In chapter 6, we developed regression models for AGB and its surrogate of ground measured LAI by using their relationship with satellite image based vegetation indices (VI). Quantification of AGB and LAI on regional scale, accurate forest type map needed. For that, in chapter 7 we studied forest type mapping.