A key tree species for forest biodiversity, European aspen (Populus tremula), is rapidly declining in boreal old-growth forest reserves

The promotion of forest biodiversity in Lucerne is conducted by the office of Landwirtschaft und Wald (Lawa). The biodiversity program 2008–2011 is coordinated with the program agreement “Biodiversität im Wald” between the federal and the cantonal authorities. The canton Lucerne has well-developed planning criteria available which allow a correct prioritization during the promotion and a goal oriented investment of the available financial resources. One difficulty with the application of the biodiversity program is the large portion of private forest owners in the canton Lucerne. The following measures which are eligible for grants and their application are discussed in more detail: old growth, forest edges, forest ponds and forest reserves.

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Epiphytic bryophytes on European aspen Populus tremula in old-growth forests in northeastern Finland and in adjacent sites in Russia

Canadian Journal of Botany ◽

10.1139/b00-023 ◽

2000 ◽

Vol 78 (4) ◽

pp. 529-536 ◽

Cited By ~ 10

Author(s):

E Ojala ◽

M Mönkkönen ◽

J Inkeröinen.

Keyword(s):

Landscape Structure ◽

Spatial Scales ◽

Regional Scale ◽

Tree Density ◽

Populus Tremula ◽

Old Growth ◽

Lobaria Pulmonaria ◽

Old Growth Forest ◽

European Aspen ◽

Old Growth Forests

We studied the occurrence and cover of epiphytic bryophytes and one lichen species (Lobaria pulmonaria (L.) Hoffm.) growing on Populus tremula L. trunks. Our aim was to explore the spatial scales where epiphyte species respond to their environment. At the landscape scale, fragmented Finnish old-growth forests close to the Russian border and farther west in a heavily fragmented landscape were compared with Russian sites with more continuous old-growth forest landscapes to assess the effect of landscape structure on epiphyte assemblages. We studied factors affecting populations at the level of individual sites and local habitat patches within the forests. Twelve sites were surveyed for epiphytes. We estimated epiphyte occurrence from 353 Populus tremula trunks. There seemed to be only minor differences in the structure of epiphyte assemblages between the three landscapes surveyed. Species richness varied also independently of the landscape structure but was positively related to regional Populus tremula abundance (alpha diversity) and the size of the substrate trunk (point diversity). At the regional scale, the most important factor affecting the occurrence of epiphytes was the abundance of Populus tremula. At the local scale, the size of the Populus tremula surveyed and tree density around the trunk surveyed correlated positively with the occurrence of some species. The size and abundance of Populus tremula as well as tree density are the most important factors for maintaining viable populations of the studied species.Key words: biodiversity, boreal forest, Bryophyte, forest management, landscape structure, Lobaria pulmonaria.

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Old-growth forest reserves in Slovenia: the past, present, and future

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2012.0240 ◽

2012 ◽

Vol 163 (6) ◽

pp. 240-246 ◽

Cited By ~ 7

Author(s):

Thomas A. Nagel ◽

Jurij Diaci ◽

Dusan Rozenbergar ◽

Tihomir Rugani ◽

Dejan Firm

Keyword(s):

Stand Structure ◽

Growth Conditions ◽

Ecosystem Functions ◽

Future Research ◽

Old Growth ◽

Forest Reserves ◽

The Past ◽

Old Growth Forest ◽

Forest Remnants ◽

Basic Characteristics

Old-growth forest reserves in Slovenia: the past, present, and future Slovenia has a small number of old-growth forest remnants, as well as many forest reserves approaching old-growth conditions. In this paper, we describe some of the basic characteristics of these old-growth remnants and the history of their protection in Slovenia. We then trace the long-term development of research in these old-growth remnants, with a focus on methodological changes. We also review some of the recent findings from old-growth research in Slovenia and discuss future research needs. The conceptual understanding of how these forests work has slowly evolved, from thinking of them in terms of stable systems to more dynamic and unpredictable ones due to the influence of natural disturbances and indirect human influences. In accordance with this thinking, the methods used to study old-growth forests have changed from descriptions of stand structure to studies that address natural processes and ecosystem functions.

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Tekstura drzewostanów naturalnych w polskich parkach narodowych na tle teorii dynamiki lasu

10.15576/978-83-66602-20-5 ◽

2021 ◽

Author(s):

Leszek Bartkowicz ◽

Keyword(s):

Tree Species ◽

Stand Structure ◽

Basal Area ◽

Site Conditions ◽

Gap Dynamics ◽

Old Growth ◽

Mosaic Pattern ◽

Spruce Forests ◽

Old Growth Forest ◽

Patch Mosaic

The aim of the study was to compare a patch-mosaic pattern in the old-growth forest stands developed in various climate and soil conditions occurring in different regions of Poland. Based on the assumption, that the patch-mosaic pattern in the forest reflect the dynamic processes taking place in it, and that each type of forest ecosystem is characterized by a specific regime of natural disturbances, the following hypotheses were formulated: (i) the patches with a complex structure in stands composed of latesuccessional, shade-tolerant tree species are more common than those composed of early-successional, light-demanding ones, (ii) the patch-mosaic pattern is more heterogeneous in optimal forest site conditions than in extreme ones, (iii) in similar site conditions differentiation of the stand structure in distinguished patches is determined by the successional status of the tree species forming a given patch, (iv) the successional trends leading to changes of species composition foster diversification of the patch structure, (v) differentiation of the stand structure is negatively related to their local basal area, especially in patches with a high level of its accumulation. Among the best-preserved old-growth forest remaining under strict protection in the Polish national parks, nineteen research plots of around 10 ha each were selected. In each plot, a grid (50 × 50 m) of circular sample subplots (with radius 12,62 m) was established. In the sample subplots, species and diameter at breast height of living trees (dbh ≥ 7 cm) were determined. Subsequently, for each sample subplot, several numerical indices were calculated: local basal area (G), dbh structure differentiation index (STR), climax index (CL) and successional index (MS). Statistical tests of Kruskal- Wallis, Levene and Generalized Additive Models (GAM) were used to verify the hypotheses. All examined forests were characterized by a large diversity of stand structure. A particularly high frequency of highly differentiated patches (STR > 0,6) was recorded in the alder swamp forest. The patch mosaic in the examined plots was different – apart from the stands with a strongly pronounced mosaic character (especially subalpine spruce forests), there were also stands with high spatial homogeneity (mainly fir forests). The stand structure in the distinguished patches was generally poorly related to the other studied features. Consequently, all hypotheses were rejected. These results indicate a very complex, mixed pattern of forest natural dynamics regardless of site conditions. In beech forests and lowland multi-species deciduous forests, small-scale disturbances of the gap dynamics type dominate, which are overlapped with less frequent medium-scale disturbances. In more difficult site conditions, large-scale catastrophic disturbances, which occasionally appear in communities formed under the influence of gap dynamics (mainly spruce forests) or cohort dynamics (mainly pine forests), gain importance.

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Relationships between Structural Indices and Conventional Stand Attributes in an Old-Growth Forest in Southeast Europe

Forests ◽

10.3390/f11010004 ◽

2019 ◽

Vol 11 (1) ◽

pp. 4 ◽

Cited By ~ 4

Author(s):

Srđan Keren ◽

Miroslav Svoboda ◽

Pavel Janda ◽

Thomas A. Nagel

Keyword(s):

Species Diversity ◽

Tree Species ◽

Structural Heterogeneity ◽

Tree Species Diversity ◽

Southeast Europe ◽

Old Growth ◽

Old Growth Forest ◽

Plot Area ◽

Stand Attributes ◽

Structural Indices

Structural indices are often proposed as guiding measures for increasing structural heterogeneity. However, few studies have examined the association between such indices and conventional stand attributes. The primary objectives of this study were to evaluate changes in structural heterogeneity and tree species diversity at different plot sizes and to quantify the relationships between conventional stand attributes (mean tree diameter, absolute tree density, basal area, species proportion) and structural indices in a mixed old-growth forest in Southeast Europe. Paired tests were used to identify significant changes in structural heterogeneity with increased plot area, while the relationships between stand attributes and analyzed indices (Gini, diameter differentiation, species mingling, and Shannon’s index) were evaluated with Pearson’s correlations. The index values of Gini, diameter differentiation, and tree species mingling were rather stable with the increase of plot size, whereas tree species diversity increased significantly with the increase of plot area from 200 m2 to 1500 m2. The measures of tree species mingling and tree species diversity were strongly associated with each other, while their association with diameter variability was weak to moderately strong. Tree species mingling index was strongly associated with the changes in tree species proportions. However, conventional stand attributes were generally not strongly correlated with the examined indices. For restoring and maintaining old-growth characteristics, forest managers may use structural indices to increase small-scale structural heterogeneity, tree species mingling, and diversity, but only as an additional set of measures, not as surrogates for conventional stand attributes.

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Species Association of the Dominant Tree Species in an Old-Growth Forest and Implications for Enrichment Planting for the Restoration of Natural Degraded Forest in Subtropical China

Forests ◽

10.3390/f10110957 ◽

2019 ◽

Vol 10 (11) ◽

pp. 957 ◽

Cited By ~ 2

Author(s):

Liu ◽

Zhu ◽

Wang ◽

Ma ◽

Meng

Keyword(s):

Tree Species ◽

Rank Correlation ◽

Economic Benefits ◽

Natural Forests ◽

Subtropical China ◽

Old Growth ◽

Species Association ◽

Old Growth Forest ◽

Enrichment Planting ◽

Adult Trees

Subtropical natural forests are unique due to their ecological and economic functions. However, most of these forests are highly degraded, which impairs the ability to provide ecological and economic benefits. Enrichment planting is an important approach to restore natural degraded forests. Species arrangement is of great importance to inform enrichment planting. Species association refers to the interrelationship of different species occupying a habitat and is a static description of the organic connection formed by the interaction of species. Species association, therefore, provides a scientific basis for species arrangement in enrichment planting. Additionally, because an old-growth forest is a climax community that has attained great age without significant disturbance, the species association in an old-growth forest can provide valuable information on the reference conditions for forest management. In this study, the species association between dominant tree species (including saplings and adult trees) was investigated in an old-growth forest in the Gutianshan National Nature Reserve in Zhejiang province in subtropical China. The objective of the study was to inform species arrangement for enrichment planting. The result showed that the overall species association exhibited a significant net positive association, indicating a dynamic balance of stable structure and species composition in the old-growth forest. Additionally, the pairwise species association was examined using the χ2 test, the Dice index, and Spearman’s rank correlation coefficient; significant positive and negative pairwise species associations were detected. Based on the species association and the light requirements of the tree species, an optimal species arrangement was determined to support enrichment planting for restoring natural degraded forests. It is expected that the results of this study will contribute to the restoration of natural degraded forests in subtropical China.

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Epiphyte Flora and Diversity on Basal Trunks of Six Old-Growth Forest Tree Species in Southern and Middle Boreal Finland

The Lichenologist ◽

10.1006/lich.1996.0043 ◽

1996 ◽

Vol 28 (5) ◽

pp. 443-463 ◽

Cited By ~ 72

Author(s):

Mikko Kuusinen

Keyword(s):

Tree Species ◽

Boreal Forests ◽

Forest Tree ◽

Old Growth ◽

Epiphytic Lichen ◽

Generalist Species ◽

Salix Caprea ◽

Forest Tree Species ◽

Old Growth Forest ◽

Habitat Generalist

AbstractEpiphytic lichen and bryophyte species composition, richness and diversity were surveyed on basal trunks of six common old-growth forest tree species, Picea abies, Pinus sylvestris, Betula pendula, Alnus incana, Salix caprea and Populus tremula, in two old-growth forest areas, one in southern and one in middle boreal Finland. The average species numbers per tree ranged from 18 (Picea) to 27 (Salix) in the southern and from 20 (Populus) to 31 (Salix) in the middle boreal area. A few widespread habitat-generalist species, such as the foliose lichens Hypogymnia physodes and Platismatia glauca, were most abundant on all the tree species, except Populus. Most other epiphyte species showed at least a slight preference for one or two tree species. Populus proved to have the most distinct flora characterized by the abundance of certain, rather specialized crustose lichens and bryophytes. The number of species that occurred on only one tree species was highest on Populus (9) in the southern and on Alnus (18) in the middle boreal area. Differences in bark acidity and structure were the most likely explanations for the differences between tree species in the epiphytic flora and diversity. Salix and Populus were the most important of the tree species studied for the conservation of epiphyte diversity in the boreal forests of Finland.

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