Light response of Fagus sylvatica L. and Abies alba Mill. in different categories of forest edge - Vertical abundance in two silvicultural systems

- We compared silver fir and beech in managed Dinaric karst forests during three years.
- Quantum yield was studied in same four light microsites for beech and silver fir.
- Response of species within microsites of forest edge was different.
- Microsite abundance in two different silvicultural systems changed with altitude.
- Share of microsites above 700 m ASL was the same regardless to the silvicultural system.

In managed Dinaric montane fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) forests, the light response of young beech and fir in gap microsites was studied during three consecutive growing periods (2009, 2010, and 2011) under controlled environmental conditions in stands of single-tree and irregular shelterwood silvicultural system. According to maximal quantum yield, the different response between species in microsite light categories was evidenced for silver fir on microsites with predominating diffuse light and for beech on microsites with predominating direct light, respectively.Abundance and change of share in microsite light categories was compared over different elevation belts on comparable sites between two silvicultural systems. The share of forest edge area was bigger in the irregular shelterwood system. Change in width of forest edge (20, 30 and 40 m) did not affect the proportion and share of the microsite in both regions of different silvicultural system. Separation of microsite areas between both silvicultural systems, evident in lower elevation belts was not evident in the most conflict and highest elevation zone, while the absolute values of all categories above 700 m in both systems were almost identical, indicating the same, small-scale irregular shelterwood system, known also as the freestyle silvicultural approach.