1.

Post-disturbance treatments and stand restoration success in beech forest sites

This dissertation comprises three studies. In the first study we examined the influence of salvage logging on forest regeneration following small to medium-scale moderate severity disturbances in eight mixed beech (Fagus sylvatica L.) dominated forest stands in Slovenia where part of the disturbed area was salvaged and the adjacent part was not salvaged. Results show that there were no significant differences in terms of densities, height structure and regeneration growth between treatments. Minor differences indicate that the non-salvaged sites tended to have a slightly more well-developed (taller) regeneration layer that remained from the previous stand and was not damaged during harvesting, while salvaged sites had a larger proportion of shade intolerant tree species due to the removal of damaged timber, which created minor soil disturbances and space for easier recruitment of regeneration. The results suggest that salvage logging following small-scale intermediate severity disturbances may not hinder forest recovery in mixed beech dominated forests. In the second study we analyzed the differences between planted and natural regeneration on three research areas disturbed by storms in 2008. We established sampling plots of natural regeneration where the dominant trees of the natural regeneration were measured and sampling plots with artificial regeneration where all planted seedlings were measured. Within both plot types, smaller vegetation subplots were established where the cover of each plant species was estimated and natural regeneration was counted. Results show that the success of the natural regeneration varied between research areas and study sites. Natural regeneration densities in Trnovski gozd were not sufficient due to the more extreme ecological conditions, while at the Bohor area the densities were high. On the upper slope of Črnivec, the natural regeneration was inhibited by thick grass of Deschampsia flexuosa (L.) Trin. Average densities of natural regeneration were 3-4 times higher on the plots with natural regeneration, which may be due to collateral damage to natural regeneration during ground vegetation removal on planted sites. In the third part of the dissertation, we studied secondary succession after forest fire at Mozirska Požganija. In 2013 we remeasured the plots established and inventoried in 1981. Results indicate that tree species, height, layer and crown depth positively influenced tree survival. Spruce showed the highest survival probability, followed by Betula pendula (Roth.), Populus tremula (L.) and Salix caprea (L.). The high initial proportion of spruce and its increasing share indicates the pioneer characteristics of a species that can easily compete with pioneers and later establish as a late successional species after pioneers retreat from the stands.

D.09 Tutoring for postgraduate students

COBISS.SI-ID: 872567

2.

Insight to sleet damage - Workshop on forest management and silvicultural measures after large scale natural disturbances

In may 2015, together with Slovenian forestry institute and Slovenian forest service, we organized a two day workshop with a focus on forest management in silvicultural measures after large scale disturbances. On the first day indoor and outdoor presentations on Rožnik hill were organized. German colleagues presented their experiences with windthrow restoration in private forests of Porurje region, Germany. The following day we visited Sevnica region, where local foresters of Slovenian forest service presented the practical examples. http://eprints.gozdis.si/1256/2/ZBORNIK_delavnica_pogled_%C5%BEled.pdf

C.06 Editorial board membership

COBISS.SI-ID: 279506176

3.

Alternative approach to forest tending

Traditional practice of forest tending is becoming more and more economically demanding. On the other hand we can reach sufficient effects of tending via focusing on smaller number of crop trees. firstly, we can prologue the periods of indirect tending of young trees under the forest canopy. When this is not possible and direct tending needs to be applied we focus on smaller number of high quality crop trees (preferably broadleaves, ca. 100 ha-1) with removing the surrounding competitor trees.

F.10 Improvements to an existing technological process or technology

COBISS.SI-ID: 4241062

4.

Alternative tending of young forest: Is it possible to achieve quality forest tending with less time and more knowledge invested?

Extension lectures for Forest owners association Sopota - Laško on 6.1.2016. Extension was visited by more than 60 attendants, such as forest owners, forest experts and employees of Slovenian forest service. Lecture consituted of the origin and role of tending paradigm, connection between silvicultural systems and tending of young forest, traditional tending of even-aged stands, and historical development and types of alternative forest tending approaches in even-aged stands. After lecture a lively discussion took place since alternative tending approaches are introducing some novelties that can significantly reduce economic investment and likely also the stability of the stands.

F.18 Transfer of new know-how to direct users (seminars, fora, conferences)

COBISS.SI-ID: 4587174

5.

Alternative forest tending

Co-organizing the extension for Slovenian forest service employees of Nazarje regional unit on the topic of new approaches in forest tending. In first lecture we compared the traditional and alternative tending approach, where only a limited number of crop trees are released. Also economics of each approach was presented. In the second lecture a study of efficiency of each approach is presented. In the afternoon, we made an excursion to the study site where three tending approaches were used: (1) traditional tending; (2) reduced traditional tending (only the most urgent measures performed) and (3) alternative tending where 400 crop trees per ha were released.