title: Gap dynamics and structure of two old-growth beech forest remnants in Slovenia.
abstract: BACKGROUND
  Due to a long history of intensive forest exploitation, few European beech (Fagus sylvatica L.) old-growth forests have been preserved in Europe.
  
  
  METHODS
  We studied two beech forest reserves in southern Slovenia. We examined the structural characteristics of the two forest reserves based on data from sample plots and complete inventory obtained from four previous forest management plans. To gain a better understanding of disturbance dynamics, we used aerial imagery to study the characteristics of canopy gaps over an 11-year period in the Kopa forest reserve and a 20-year period in the Gorjanci forest reserve.
  
  
  RESULTS
  The results suggest that these forests are structurally heterogeneous over small spatial scales. Gap size analysis showed that gaps smaller than 500 m(2) are the dominant driving force of stand development. The percentage of forest area in canopy gaps ranged from 3.2 to 4.5% in the Kopa forest reserve and from 9.1 to 10.6% in the Gorjanci forest reserve. These forests exhibit relatively high annual rates of coverage by newly established (0.15 and 0.25%) and closed (0.08 and 0.16%) canopy gaps. New gap formation is dependant on senescent trees located throughout the reserve.
  
  
  CONCLUSIONS
  We conclude that these stands are not even-sized, but rather unevenly structured. This is due to the fact that the disturbance regime is characterized by low intensity, small-scale disturbances.
authors: Biotechnical Faculty, Department of Forestry and Renewable Forest Resources, University of Ljubljana, Ljubljana, Slovenia. tihomir.rugani@bf.uni-lj.si
authors: Tihomir
authors: T
authors: Rugani
authors: Jurij
authors: J
authors: Diaci
authors: David
authors: D
authors: Hladnik
mesh_terms: D029964:Fagus / Q000254:growth & development*; D016468:Forestry / Q000379:methods; D017524:Slovenia; D014197:Trees / Q000254:growth & development*