Research Article |
Corresponding author: Ivo Machar ( ivo.machar@upol.cz ) Academic editor: Yrjö Haila
© 2017 Ivo Machar, Vit Vozenilek, Jaroslav Simon, Vilém Pechanec, Jan Brus, Petr Fulnecek, Tomas Vitek.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Machar I, Vozenilek V, Simon J, Pechanec V, Brus J, Fulnecek P, Vitek T (2017) Joining of the historical research and future prediction as a support tool for the assessment of management strategy for European beech-dominated forests in protected areas. Nature Conservation 22: 51-78. https://doi.org/10.3897/natureconservation.22.12902
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European beech-dominated forests are crucial for maintaining biodiversity in forested mountain landscapes of the European temperate zone. This paper presents the results of research and assessment of management strategy for mountain beech-dominated forests in the Jeseníky Mountains (Czech Republic). Our approach is based on combining research on historical development of the forest ecosystem, assessment of its current state, and predictions of future dynamics using a forest growth simulation model. Using such a method makes it possible to understand the current state of the mountain beech-dominated forest ecosystem and predict its future development as a response to specific management strategies. The application of this method is therefore appropriate for assessing the suitability of selected management strategies in mountain protected areas. Our results show that a non-intervention management for mountain beech forest in the next 80 years complies with the Natura 2000 requirement to maintain the existing character of the forest habitat. Thus, the current management plan for the beech-dominated forests in the Jeseníky Mountains does not require significant corrections in the context of its conservation targets (i.e. maintaining biodiversity and current character of the forest ecosystem dominated by beech). The results of this study suggest that combining the knowledge on historical development with forest growth simulation can be used as a suitable support tool to assess management strategies for forest habitats in protected areas.
Beech-dominated forest, biodiversity, forest history, forest management plan, growth simulation model, Natura 2000
Because most of the forests in Europe have been influenced by human activity, primeval forests currently account for less than 1 % of the total area of European forests (
Primeval European beech forests consist of a mosaic of sub-stands which can be typified to the developmental stage (phase) by the structure of the tree layer (
European beech and fir-beech forests are the predominant types of natural potential vegetation from planar to montane vegetation zones of temperate Europe (
The theory of the small development cycle has a long history. In 1959 Leibundgut developed the former idea of
(1) A fraction of a beech forest stand becomes disturbed (e.g. by windfall).
(2) The first phase of the tree layer regeneration is dominated by pioneer trees (e.g. Betula sp.) in open space of the disturbed patch, while the old beech trees along the border of the open disturbed area are going to die off owing to “sunburn” (the cambium of the exposed beech trunks dies).
(3) Regeneration starts in the shadow of the pioneer trees and a new forest stand, again dominated by beech, builds up. Remmert finished the description of this cycle with the words: “Very often there is a short-cut in the cycle, and beech follows beech”.
It is interesting, that Remmert’s former idea about European beech maintaining dominance across the full forest development cycle has been confirmed in current studies (e.g.
In 1995 Korpel published extensive results regarding the primeval European beech dominated forests in Slovakia (Appendix 1: fig. A1). The numerous examples presented in this study document the lack of pioneer-dominated phases in the regeneration cycle; beech, fir and spruce dominate all the regeneration phases. These results are supported by modelling of the tree species composition during the regeneration process. The most important parameters in competition amongst trees are height increment and shading capacity combined with shade tolerance. The European beech is a shade tree, and middle-aged and old growth beech have high rates of annual height increment. Models based on these parameters (e.g.
Currently the theory of the small development cycle is, in literature, also known as the concept of forest gap dynamics (
Gap dynamics now only exist in strictly protected areas, because the most of European beech dominated forests have been managed in line with the paradigm of the Central European forestry (
Primeval European beech forests have higher stand diversity (at the level of structural and tree species diversity) than commercial forests on comparable sites (
The structure of managed and unmanaged European beech-dominated forests (Bílek et al. 2011) and their treefall gap dynamics (
The near-natural and virgin ecosystems of European beech and fir-beech montane forests are characterized by a long-term cyclical alternating dominance of two main species: Silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.), (
Preserved segments of European beech-dominated forests represent valuable natural laboratories (
The main objective of this paper is to show the importance of integrating historical research of forest ecosystems for the assessment of forest management strategy, using an example of protected mountain beech and fir-beech forests of temperate Europe. The particular targets of this paper are:
a) to explain the current state of the beech-dominated forest ecosystem in two study sites using historical analysis of their past,
b) to predict the likely future trend in the dynamics of forest stands using a growth simulation model,
c) to review the current forest management plan and decide whether it ensures maintaining the current character of the habitat and thus complies with the Natura 2000 conservation objectives for forest habitats.
The research was conducted at two mountain study sites (Fig.
The Jelení Bučina (JB) study site (45.84 ha) is located at 50°06'N, 17°17'E, 740–920 m above sea level on a mostly steep north-west slope with a gradient of 23 %. The local bedrock geology consists of paragneiss. The soil is very stony with debris, mostly Ranker mesotrophic cambisols with the moder humus type. Most of the study site (91%) is covered by natural beech forest of an old-growth character with small patches of Tilio-Acerion ravine forest and minor fragments of Caricion remotae forest springs. This forest stands can be considered as forests sensu
The Bučina pod Františkovou Myslivnou (BFM) study site (25.49 ha) is located at 50°03'N, 17°11'E, 1050–1105 m above sea level. This site represents the highest-elevation beech forest in the entire Jeseníky Mountains. At higher altitudes, the beech forest naturally transforms into a natural spruce forest ecosystem (
According to the classification system of the Natura 2000 network, both study sites are classified as “Medio-European subalpine beech woods with Acer and Rumex arifolius” (habitat code 9140). According to the Habitat Catalogue of the Czech Republic (
Data sources and analysis of historical development of forest ecosystems in the study sites
To study the historical development of forests in the JB and BFM study sites in the period of 1621–1947, we used the historical documents of the Teutonic Order, a former owner of the studied forests. The set of original documents is stored in the State Regional Archive in Opava in the “Central Administration of the Teutonic Order – Bruntál Estate” collection numbered 1.477–1.543 and forestry maps numbered 5.799–5.802, 5.945, 5.948 and 5.955 in scale 1:2880 In addition, we used several archive materials from the State Regional Archive in Janovice from the collections “Loučná Estate” and “Velké Losiny Estate”. Since 1947, the forests in both study sites have been owned by the state. Valuable historical data for this period were found in the forest management plans deposited in the archives of the Forest Management Institute in Brandýs nad Labem. Recent data necessary for the analysis were taken from the forest management records deposited at the JMPLA administration office.
Prediction of future dynamic of forest ecosystems in the study sites
To predict the future forest development in the JB and BFM study sites, we used the SIBYLA growth simulation model (
At both study sites research plots were defined in such a way that they reflected the characteristic conditions of the forest in the study sites and their typical tree species composition (Table
Forest stand characteristics for the Jeleni Bucina (JB) and Bucina pod Frantiskovou Myslivnou (BFM) study sites as used for the growth simulation model.
Study site | GPS coordinates | Type of forest ecosystem | Tree species composition (% proportion in the forest stand) |
---|---|---|---|
JB | 50.06633°N, 17.17945°E | Highly heterogeneous mountain beech forest with patches of natural regeneration | Canopy layer in the disintegration stage: BK 60, KL 20, JL 10, SM 10 |
Understory formed by isolated patches of natural beech regeneration: BK 100 | |||
BFM | 50.03446°N, 17.11800°E | Highly heterogeneous mountain beech forest with extensive natural regeneration and admixture of fir | Canopy layer in the optimum stage: BK 94, KL 3, JL 1, SM 1, JD 1 |
Understory formed by patches of natural regeneration diffused over the entire site: BK 96, JD 4 |
All trees wider than 5 cm of DBH were located and marked in a rectangular coordinate system. The following parameters were measured: diameter of the tree trunk at 1.3 m (diameter at breast height, d1.3), total height of the tree (m), height of green tree top setting, and social position. We employed the dendrometric measurements from all research plots to create stand height curves, using the non-linear Naeslund regression height function.
In 2012, we carried out visualization and simulation of the future forest development under a non-intervention management (i.e. spontaneous forest development in relation to conservation targets of Natura 2000 sites) using a growth simulation model. The growth simulation was based on a mortality model, consisting of two components: probability of tree necrosis (
For both study sites we predicted changes in tree diameter diversity of the beech stands (excluding individuals originating from natural regeneration) and changes in their standing tree volumes (m3.ha-1). Further, we evaluated the development of tree species composition, representation, and horizontal and vertical structure using the following structural indices: Clark-Evans aggregation index (
Linking historical research with growth simulation model to assess forest management strategies in the study sites
The assessment of forest management strategies currently implemented in the JB and BFM study sites is based on combining research of historical development of the studied ecosystem and interpretation of future development of main edificators predicted by the growth simulation model. The historical research helps to objectively explain the current state of the forest ecosystem determined by the forest management and other human activity carried out in the study sites. The growth simulation model of future forest development predicts the structure of woody vegetation over defined time periods in the future based on specific management strategies delineated in the protected areas management plan.
The final synthesis based on the results of both analyses (historical research and growth simulation) allows the assessment of whether the spontaneous (succession) development of the ecosystem resulting from the current forest management plan ensures maintaining the existing character of the mountain beech forest habitat as defined by Natura 2000 (
Until the 12th century, the Jeseníky Mountains were part of the “borderline forests”, an unpopulated and forested border mountain chain that formed a natural defense of lowland areas of the Bohemian Kingdom, intensely inhabited since the Neolithic period (
Historical development of the BFM study site was essentially similar. At the turn of the 19th century the site was covered by an old forest stand dominated by beech, admixed with spruce, sycamore maple and elm. Until the end of the 18th century, selective logging was applied to support natural regeneration of beech. Around 1800, the old trees were almost completely harvested but it is not known whether it was a deliberate timber extraction or a forced harvest after a windstorm (
The main findings from the historical analyses of both study sites can be generalized for Central European mountain beech forests as follows:
A) A decrease in the occurrence of fir and a stable dominance of beech in natural forests is obvious during the long-term history of forest stands.
B) Despite the influence of human activity, most beech forests in protected areas can be considered as natural forests with natural dynamics.
C) In fully protected areas we can identify the first generation forest stands following former primary old-growth forest, resulting mostly from natural regeneration with a high potential for maintaining natural forest dynamics (and biodiversity) under the theory of the small development cycle.
Visualization of the growth simulation results for the JB study site shows that “non-intervention management” induces significant changes in the forest structure (compared to the current state) already in the first forecast horizon (25 years) (Fig.
Figure
The long-term trend of spontaneous transition of forest ecosystems on both study sites from the disintegration stage to the growth stage is documented by the timber stocks prediction model (Fig.
Table
The main conservation target of the management plan for both nature reserves as well as Natura 2000 sites (comprising the JB and BFM study sites) is to maintain the current character of the habitat, as required by the European Union Habitat Directive No. 92/43/EEC. From this perspective, it is notable that the growth simulation model predicts changes in the spatial structure and shifts in the development stages of modeled forest ecosystems under the non-intervention regime for the next 80 years (see 3.2), but it does not assume any significant changes in the character of the habitat code 9140 as defined by the Natura 2000 classification system.
Growth simulation model for the Jeleni Bucina study site: current state (A) and future forest development for the periods of 25 years (B), 50 years (C), 80 years (D) (light blue: Fagus sylvatica, dark blue: Acer pseudoplatanus, red: Picea abies).
Growth simulation model for the Bucina pod Frantiskovou Myslivnou study site: current state (A) and future forest development for the periods of 25 years (B), 50 years (C), 80 years (D) (light blue: Fagus sylvatica, dark blue: Acer pseudoplatanus).
Time development of the leaf area index in study site Jeleni Bucina (solid line) and Bucina pod Frantiskovou Myslivnou (dashed line) for prediction period of 80 years.
Naeslund height function for both study sites: Jeleni Bucina (solid line) and Bucina pod Frantiskovou Myslivnou (dashed line).
Prediction of time changes in tree diameter diversity (cm) of the beech stands in study site Bucina pod Frantiskovou Myslivnou.
Prediction of time changes in tree diameter diversity (cm) of the beech stands in study site Jeleni Bucina.
Prediction of time changes in standing tree volumes (m3.ha-1) for both study sites: Jeleni Bucina (solid line) and Bucina pod Frantiskovou Myslivnou (dashed line).
Indices prediction on the Jeleni Bucina (JB) and Bucina pod Frantiskovou Myslivnou (BFM) study sites after spontaneous development.
Time of simulation | Index | |||||
---|---|---|---|---|---|---|
Clark-Evans index | Arten-profil index | Pielou segregation index | ||||
JB | BFM | JB | BFM | JB | BFM | |
0 | 0,880 | 0,852 | 0,574 | 0,463 | 0,437 | 0,442 |
5 | 0,880 | 0,852 | 0,578 | 0,467 | 0,434 | 0,448 |
10 | 0,886 | 0,865 | 0,615 | 0,489 | 0,483 | 0,498 |
15 | 0,923 | 0,855 | 0,623 | 0,469 | 0,533 | 0,515 |
20 | 0,942 | 0,860 | 0,618 | 0,474 | 0,527 | 0,522 |
25 | 0,953 | 0,864 | 0,592 | 0,470 | 0,492 | 0,508 |
30 | 0,967 | 0,897 | 0,613 | 0,498 | 0,525 | 0,545 |
35 | 0,963 | 0,897 | 0,600 | 0,498 | 0,536 | 0,548 |
40 | 0,960 | 0,897 | 0,588 | 0,488 | 0,527 | 0,548 |
As a consequence of changing climatic conditions in Europe (CO2 content, air temperature, precipitation, heat waves and drought episodes) it is expected that European beech forests will change in the future (
Predicting future forest dynamics in stand-scale is an essential component of sustainable forest management (
The multidisciplinary combination of the two different methods (from social and natural sciences) helps to make the assessment of forest management strategies in conservation areas more objective, as it enables the prediction of likely development of forest stands under specific management plans in a specific nature reserves (
Based on the combined results of the growth simulation model and the historical analysis, it is possible to evaluate the current management strategy and suggest potential adjustments in the forest management plan, in order to comply with the mission of a protected area, i.e. retaining the defined habitat character and biodiversity (
Simulation results for both study sites support the theory that the anthropogenic influence is a major cause of fir decline in European mountain beech forests (
The relative value of LAI depends on the character of assimilation organs, that is, on a forest type, as demonstrated by empirical measurements by
The computed shape of stand height curves is characteristic only for a particular stand age, and the curves shift with stand age (
Differences in altitude occurrence of European beech can be considered as influences of past silvicultural management (
The historical analysis of forest development on both study sites revealed that the current structure of forest stands is strongly influenced by the former management. If the modification of the tree species composition is desired for conservation purposes, in order to get closer to the theoretical assumption of potential vegetation, then some form of management intervention will be necessary – e.g. the artificial reintroduction of fir that disappeared due to anthropogenic activities in the past (see section 3.1).
For both study sites, the growth simulation model indicates changes in forest development over an 80-year time horizon. These future growth changes correspond with the theoretical model of the small development cycle of European temperate forests. They are significant in terms of biodiversity protection, as the long-term spontaneous development of forest ecosystems leads to the creation of valuable habitats for numerous endangered species (
Based on the synthesis of the historical research and the growth simulation model, we conclude that in the next 80 years the current non-intervention forest management, which is based on spontaneous (succession) development of the ecosystem, does not contradict the Natura 2000 requirement of protecting this habitat type. From this perspective, the forest management plan for the JB and BFM study sites (and the reserves in which they are located) does not require any corrections in the context of their conservations goals, that is, maintaining the habitat character and biodiversity.
The historical research revealed that both study sites (although having a visual character of an old-growth forest and therefore being protected as nature reserves and Natura 2000 sites) are in fact a second-generation forest following the previous primary old-growth forest. The growth simulation model for both study sites predicts a partial shift in forest stages, corresponding with the theoretical model of the small development cycle of European temperate forest. These future growth changes in the forest ecosystem are significant in terms of biodiversity protection, as the long-term spontaneous development of forest ecosystems leads to the creation of valuable habitats for numerous endangered species.
The studied forest ecosystems are part of the European network of nature protection areas – Natura 2000. The forest management strategy applied in both of the study sites, resulting from the categorization of protected areas by the IUCN (
The authors thank the Forest Management Institute in Brandýs nad Labem, Olomouc branch, for providing archive documents for the local forest management unit Loučná Estate. This study was conducted with the financial support of the “Cultural landscape of Olomouc Archdiocese – research, presentation and management” grant as a part of the NAKI II program of the Ministry of Culture of the Czech Republic.