Spatial Structure of Uneven-Aged Stands of Fir and Beech on the Borja Mountain (Bosnia and Herzegovina)

Abstract

In the territory of Bosnia and Herzegovina, uneven-aged stands of fir and beech are very important from the economic and ecological points of view. A major lack of information on the simple structure of stands is that it cannot be used to draw valid conclusions about the spatial distribution of woody species and about the position and dimensions of trees, and this is one of the bases for the sustainable management of mixed and uneven-aged forests. In four mixed uneven-aged fir and beech stands and one pure fir stand on Mt Borja, the basic elements of tree growth were measured and the data needed to determine the indicators of the spatial stand structure were determined. According to the Clark–Evans aggregation index, there is a tendency towards a uniform spatial distribution of trees in the stand in the case when all trees are observed. When only fir trees are observed, it is evident that there is a tendency to group fir trees in the stand. The diameter differentiation index shows that there is average tree diameter differentiation on all sample plots. The determined values of the Weber height competition index by stands are approximately the same, that is, it can be stated that there is no significant difference between stands in terms of competition between trees as regards the vertical structure of stands.

Keywords

• stand spatial structure
• Clark and Evans aggregation index
• diameter differentiation index
• Weber height competition index