Research Projects

ABSTRACT

The intensity and frequency of disturbances and extreme weather events has increased worldwide in recent decades. At the same time, forests are becoming less and less resistant to disturbances (i.e. windthrow, fire, insect outbreaks) due to changes in forest structure and composition, pollution, decreased tending, and ageing of forests. More than one third of annual logging in Europe and Slovenia is due to sanitary reasons, mainly natural disturbances. In the future, neglected tending and climate change will almost certainly lead to further problems. In order to reduce the impact on the ecological and economic functions of forests, it is necessary to improve forest restoration after disturbances. The restoration of forests as the basis for sustainable forest management is associated with particular risks for property and people as well as extraordinary costs and must therefore be carried out in a very  rational way.
The natural disturbances of the last two decades have affected large areas of forest, most of which are to be restored naturally. Appropriate natural regeneration and tending measures of the disturbed areas require adapted methods of planning and implementing silvicultural measures and forest policy. Research indicates a great restorative potential of ecologically and economically interesting light-demanding tree species, which often decline in the long-term due to competition from ground vegetation, lack of silvicultural tending measures and often overbrowsing. In Slovenia, decisions on supplementing natural regeneration with planting are not made on the basis of an objective assessment of the success of natural regeneration, whereas in most European countries the minimum requirements for natural regeneration are laid down in forest legislation. The current level of artificial regeneration has never been so low in the history of sustainable forest management in Slovenia. In recent decades, natural regeneration has almost completely replaced artificial regeneration of forests, so that today natural regeneration accounts for up to 90% of all forest areas. However, with the decline in the use of artificial regeneration, forest nurseries and seed production started to decline and there was no need for research on the artificial regeneration of forests and the provision of healthy seedlings for a number of tree species. New knowledge was not transferred into practice, and knowledge already acquired from the past was often forgotten, which together led to the unsatisfactory success of artificial forest restoration. Moreover, there is little research on this subject in Slovenia, and the success of artificial regeneration (after regular harvesting and after disturbances) in forests has not been evaluated from a time perspective, so we do not have the right information on how to proceed in the future. The proportion of artificial regeneration in Slovenia should be increased for two reasons: 1) in order to adapt to climate change, it is essential to plant different tree species and genetic provenances adapted to a future climate (rapid temperature changes, less precipitation, longer periods of drought, higher temperatures); 2) an increase in the intensity and frequency of natural disturbances will also increase the need for artificial regeneration of the affected stands.
The long-term success of young forests developed following natural disturbances, can only be guaranteed by planned maintenance measures. The traditional tending of young forest stands on disturbed areas is not possible for logistical and economic reasons. With the further decline in replanting and tending, there is a great risk that postdisturbance forest areas will become overgrown by ground vegetation, shrubs and even invasive species. All this poses a threat to the long-term decline of ecosystem functions, especially the protective functions against natural hazards. The long-term decline in the implementation of silvicultural measures and the poor use of subsidies from European sources indicate the inadequacy of the existing model of planning, implementation and promotion of silvicultural measures. 

The research objectives of the project are: 

• Objective 1: To develop a Europe-wide comparable method to assess the performance of natural and artificial forest regeneration using verifiable criteria (e.g. density, mixture, damage).
• Objective 2: To analyze the causes of inadequate natural regeneration and develop a model to predict regeneration, including analyzes of control fences without browsing, and proposals for restoration measures through planting.
• Objective 3: To test and propose innovative and rational ways of supplementing natural regeneration (e.g. planting wildlings, planting in groups and in selected locations).
• Objective 4: Synthesis of the current domestic and foreign knowledge on the rationalization of young forest management after natural disturbances.
• Objective 5: To provide recommendations for the planning and implementation of silvicultural measures for young forest stands restored after natural disturbances.
• Objective 6: To compare the Slovenian system of planning, implementation and  subsidization of forest restoration after natural disturbances with the developed European countries and to propose changes, especially in terms of "from subsidization measures to subsidization effects".
• Objective 7: To carry out an ecological-economic analysis of new approaches to complement natural regeneration and tending of young forests, including standards, and to compare them with existing methods.
• Objective 8: Examine the effectiveness of the system of co-financing forest regeneration after natural disturbances and forest stand tending in relation to the importance of the ecological and social functions of the forest and make proposals for improvement.
• Objective 9: To submit proposals for amendments and additions to the forestry regulations in the part relating to forest restoration and forest tending following largescale disturbances (Forest Act and implementing regulations on co-financing forest regeneration, protection and maintenance of the forest).

THE PHASES OF THE PROJECT AND THEIR REALIZATION

The project will involve researchers from the Department of Forestry and the Slovenian Forestry Institute (GIS) will participate in the project. Also, experts from the Slovenian Forest Service (ZGS ), the Slovenian State Forests (SiDG d.o.o.) and representatives of forest owners will also participate. The project will have an impact on the improvement of decision making regarding the approach to forest restoration after large-scale disturbances in the forest, both on the side of forest policy and administration and on the side of enterprises and forest owners. This will have an indirect impact on cost reduction and increased efficiency of forest regeneration and maintenance. The project will also have an impact at the European level through cooperation with leading international centres in the field of silviculture, field research, review of best practises abroad and the inclusion of complementary international projects and publications.

We have designed seven work packages (WP) to facilitate the implementation of the research objectives:

• WP1: Evaluation of the success of forest regeneration
• WP2: Causes of unsatisfactory natural regeneration
• WP3: Predicting the success of forest regeneration
• WP4: New methods for reforestation
• WP5: Tending of young forests following natural disturbances
• WP6: Improving the forest restoration system and forest policy measures
• WP7: Transfer of results into practice and project management

The individual work packages are interconnected, so that the results of one work package form the input for other work packages or the results are generated mutually, thus adding value to the project. In WP1 we will develop a method for the verification of the success of natural and artificial regeneration, based on a synthesis of previous research on natural and artificial regeneration, the study of literature and foreign legislation for the verification of regeneration success, and expert workshops with forest scientists and professionals. The method will be tested on representative objects. In DS2, we will analyse and synthesise the causes of insufficient regeneration on several research objects with permanent research plots (windbreaks 2007-2008 and 2017-2018). The conclusions of the expert workshop (WP1) and the results of the synthesis of WP2 will form the basis for the development of a model to predict the success of forest regeneration after natural disturbances based on geomorphological, habitat, climatological and forest history information (DS3). In work package 4 we will establish several experimental plantations in the forest of Biotechnical Faculty and Pahernik Estate with alternative and improved planting methods, e.g. planting of wildlings, planting in groups and at selected locations, planting of different mixtures. In DS5, we will reanalyse existing long-term experiments with situational tending, set up new ones and link up with professional forest centres in Switzerland and Austria, where we will organise workshops to train practitioners. We will also conduct comparative analyses of the economic efficiency of traditional and situational management, including standards. In DS6 we will conduct comparative analyses of the Slovenian system of planning, implementation and subsidisation of natural regeneration and forest tending with developed European countries. We will propose changes and improvements to the regulations governing forests, especially with regard to shifting the focus from supporting measures to co-financing effects. Particular emphasis will be placed on the differentiation of the substantive and financial aspects of planning and promoting forest tending in relation to the emphasis on the ecological and social functions of forests. it is increasingly perceived that the transfer of scientific, technical knowledge and, above all, of novel information into practise is slowing down. The project will therefore pay special attention to the transfer of innovative knowledge into practise (WP7). The project will connect researchers, practitioners and forest owners, so that part of the knowledge transfer will take place during the implementation of the project. In addition to the final report, brochures and professional articles, the knowledge transfer will take place through several field workshops. Information for the professional and lay public will be provided via an interactive project website and the Facebook page.

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