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  • Author: Róbert Sedmák x
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Abstract

This paper presents two alternative approaches of final cut scheduling for a fifty year strategic planning horizon. One approach is represented by cutting percentage, which is a classical timber indicator commonly used in the Czech and Slovak Republics. The second approach is represented by two optimisation models of integer programming; the first model without spatial aspect and the second model including adjacency constraints. Both optimisation models are derived for the clear cut management system with the scheduling approaches applied on an example of a forest management area with over-mature stands.

The main aim of the paper is to compare two suggested optimisation models with the classical scheduling approach and to demonstrate their positive effect on the age class distribution of forests. The further aim is to include green-up constraints in the scheduling, which respect legislative conditions. The results show that even in the case of a single management system, without considering different ecosystem services, the optimisation model that does not consider the spatial aspect gives comparable results to the approach that r includes the adjacency constraints. The primary hypothesis, that the regular age-class distribution and flow harvesting cannot be achieved when considering green-up constraints, was rejected

Abstract

The paper presents an application of structural analysis in search of key drivers and barriers of forest management in two Slovak regions: Podpoľanie and Kysuce. A comparison with factors identified in selected European regions is also presented. First, various relevant factors affecting forest management were selected for both regions. The selections draw on the pool of primary data (structured in-person interviews) and secondary data (qualitative analysis of national and European documents). Second, factors were grouped according to the STEEP categories (Society, Technology, Economy, Ecology, and Policy). Subsequently, factors were rigorously assessed by the regional stakeholders in participatory workshops, and their answers were analysed by structural analysis with the help of Parmenides EIDOS™ software. The results show that in both Slovak regions political, economic, and ecological factors dominated over social and technological factors. The comparison with selected European regions revealed that in the Slovak and other European regions, the Policy category dominated due to having the highest number of factors and their overall impact on forest management. In contrast, the least important societal domain was Technology in both the Slovak and other European regions. However, while stakeholders across the selected European regions perceived the Society domain as significant, stakeholders in both Slovak regions perceived the Economy and Ecology domains as more significant.

Abstract

Extracting cores from a tree using an increment borer has been standard practice in dendrochronological studies for a long time. Although empirical rules exist regarding how many samples to take and which methodology to apply, comparatively few studies provide quantification of the similarity of relative tree-ring-widths (TRW) around the stem circumference. The aim of this study was therefore to precisely measure the similarity of standardised TRWs around the stem circumference and to provide objective suggestions for optimal core sampling of Norway spruce (Picea abies Karst. [L.]) and European beech (Fagus sylvatica L.) growing in Central European temperate forests.

A large sample of cross-sectional discs was used from Norway spruce and European beech trees growing on various slopes, at different altitudes and biogeographic regions across the Czech Republic and Slovakia. The similarity of TRWs measured in different coring directions was analysed by testing the relativized TRW around the trunk (rTRW). Comparison of rTRWs revealed no significant differences between coring directions, indicating that the relative increment was the same around the radius. The results also showed the high similarity between the rTRWs to be independent of both slope inclination and altitude. Moreover, the reconstruction of proportional tree diameters and basal areas backward in time from one core sample and one measurement of tree diameter (basal area) at the time of sample extraction is possible with reasonable precision.

Abstract

Scenarios modelling offers to forest management an option how to envision complex future associated with various natural, social, or economic uncertainties. The challenge is what modelling method to choose as many methodological approaches to scenario building exists. Morphological analysis is a basic modelling method for structuring and analysing a whole set of relationships existing in multi-dimensional, non-quantifiable, and complex topics. Especially, its application is relevant when abstract policy or market-driven challenges need to be investigated. In this study, we demonstrated the usefulness of the morphological analysis with an example case taken from forest management in Slovakia. The use of the method has enabled, from a number of uncertain futures, to identify three possible, plausible and consistent future scenarios of possible forest management direction in the regions of Podpoľanie and Kysuce. Additionally, the future scenario modelling as prognostic method of qualitative research supported by quantitative models or forestry DSS could introduce participation and more dimensions into forest management modelling. Thus, the future scenarios modelling offers new methodological possibilities to how to deal with increasing uncertainties associated with increasing demands for various ecosystem services or negative impacts of climate change, that forest management in Slovakia will face in the near future.

Abstract

Project COST Action FP 0804 - FORSYS summarizes European experiences in developing and applying decision support systems for forest management. This paper introduces FORSYS methodology for the classification of current forest management problems and for the description of existing decision support systems. The paper identifies the general forestry planning problems that need to be solved in Slovakia, lists the DSS tools available in Slovakia and evaluate their ability for addressing the identified problems. Finally, the research needs and gaps in this field were identified. A comparison of the situation regarding decision support in Slovakia and both in Europe and neighbouring countries (Austria, Hungary) is introduced in order to justify the identified needs. The paper is focused on the overview of models, methods and knowledge management techniques which are available in Slovakia now. We found out that the Slovak decision support research follows the state in Europe with a significant time delay and a lack of adequate instruments for addressing the contemporary planning problems exists. Consequently, there is a strong need for the development and application of computer-based tools to support decision-making problems in forest management.

Abstract

The main objective of the study is to facilitate cross-dating of sensitive tree-ring series from living European beech (Fagus sylvatica L.) trees in the absence of a regional chronology. The main idea lies in the preliminary dating of marker rings or ring patterns visually identified on the wood (before the ring-width measurements), which is independently validated through a moving correlation between a tentative reference chronology and instrumental climate records (after the ring-width measurements). Following the detection of low moving correlations, potentially misdated segments or series are re-examined and a new tentative reference chronology is constructed. The process is repeated as long as a higher correlation with climate is obtainable. The applicability of this method was investigated on three difficult-to-date sets of tree-ring series of beech trees which were growing at temperature- or precipitation-sensitive locations in under-canopy or canopy positions. A good ability of the combined method for the cross-dating was practiced on datasets almost impossible to cross-date by commonly used approaches. Highlighting the actual correlation of ring widths with climate in tree-ring series makes the cross-dating process more independent from human decisions, so the com-bined cross-dating has the potential to improve the reliability of various dendrochronological studies.