Deadwood Density and Moisture Variation in a Natural Temperate Spruce-Fir-Beech Forest

Deadwood represents a source of nutrients, carbon and water for metabolism within forest ecosystem. Nutrients are mobilized due to the decomposition of wood, which is a long-term process that can be best studied by analysing environmental data on a temporary scale. Our study provides physico-temporal data on the downed logs of three major tree species in European temperate forests: Abies alba Mill., Fagus sylvatica L. and Picea abies (L.) Karst. Time since death was obtained using tree censuses (repeated for 40 years) and dendrochronology for each single downed log, the oldest being 75 years old. Standard laboratory methods were used for the determination of wood density and moisture changes. F. sylvatica was decomposed rapidly in the initial phase – mass loss was 50% during the 5 years after death, while A. alba and P. abies lost 13% and 16%, respectively. Downed logs of F. sylvatica contained 391 kg of water per m3, while these of P. abies 279 kg. A log-transformed linear model was created that shows the dependence of time since death on mass loss. According to the model, F. sylvatica had the shortest total decomposition time (39 years), followed by A. alba (58 years) and P. abies (86 years).

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Evidence of elevation-specific growth changes of spruce, fir, and beech in European mixed mountain forests during the last three centuries

Canadian Journal of Forest Research ◽

10.1139/cjfr-2019-0368 ◽

2020 ◽

Vol 50 (7) ◽

pp. 689-703 ◽

Cited By ~ 2

Author(s):

Hans Pretzsch ◽

Torben Hilmers ◽

Peter Biber ◽

Admir Avdagić ◽

Franz Binder ◽

...

Keyword(s):

Abies Alba ◽

European Beech ◽

Spatiotemporal Pattern ◽

Silver Fir ◽

Mountain Forests ◽

Growth Trend ◽

Dependent Change ◽

Fagus Sylvatica L ◽

Growth Changes

In Europe, mixed mountain forests, primarily comprised of Norway spruce (Picea abies (L.) Karst.), silver fir (Abies alba Mill.), and European beech (Fagus sylvatica L.), cover about 10 × 106 ha at elevations between ∼600 and 1600 m a.s.l. These forests provide invaluable ecosystem services. However, the growth of these forests and the competition among their main species are expected to be strongly affected by climate warming. In this study, we analyzed the growth development of spruce, fir, and beech in moist mixed mountain forests in Europe over the last 300 years. Based on tree-ring analyses on long-term observational plots, we found for all three species (i) a nondecelerating, linear diameter growth trend spanning more than 300 years; (ii) increased growth levels and trends, the latter being particularly pronounced for fir and beech; and (iii) an elevation-dependent change of fir and beech growth. Whereas in the past, the growth was highest at lower elevations, today’s growth is superior at higher elevations. This spatiotemporal pattern indicates significant changes in the growth and interspecific competition at the expense of spruce in mixed mountain forests. We discuss possible causes, consequences, and silvicultural implications of these distinct growth changes in mixed mountain forests.

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Reconstruction and actual trends of landslide activities in Bruust–Haltiwald, Horw, canton of Lucerne, Switzerland

Geographica Helvetica ◽

10.5194/gh-74-93-2019 ◽

2019 ◽

Vol 74 (1) ◽

pp. 93-103

Author(s):

Philippe Burkhalter ◽

Markus Egli ◽

Holger Gärtner

Keyword(s):

Abies Alba ◽

Reaction Wood ◽

Lake Lucerne ◽

Geomorphological Mapping ◽

Eccentricity Index ◽

Fagus Sylvatica L ◽

The Common ◽

Definition Of ◽

Significant Concentration

Abstract. A spatiotemporal reconstruction of slope movements on the edge of Lake Lucerne near the municipality of Horw, canton of Lucerne, is presented. The reconstruction was realized by analyzing growth reactions of beech (Fagus sylvatica L.) and fir (Abies alba Mill.) trees growing on this slope. Before dendrochronological sampling, a detailed geomorphological mapping of the landslide was conducted with the aim to determine the spatial extent of the sliding area. For tree-ring analyses, 124 increment cores from 62 trees were analyzed following standard techniques of dendrogeomorphology. In addition, long micro-sections were prepared from the entire cores to extend the common eccentricity analyses by microscopic determination of the onset of reaction wood in fir and beech. Results clearly show that the area is moving at least since 1948. A significant concentration of events was observed between the years 1990 and 2000 as well as after 2006. The definition of a threshold to define events using an eccentricity index alone is problematic and needs to be adapted to specific site conditions. For this reason, we recommend always combining the application of an eccentricity index with a detailed visual (anatomical) inspection to check for the occurrence of reaction wood.

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A prognosis for the impact of climate change on beech stand dynamics in the Polish and Ukrainian Roztoche region

Forest Research Papers ◽

10.1515/frp-2017-0016 ◽

2017 ◽

Vol 78 (2) ◽

pp. 149-158

Author(s):

Ihor Kozak ◽

Barbara Typiak ◽

Taras Parpan ◽

Hanna Kozak

Keyword(s):

Abies Alba ◽

Time Span ◽

Silver Fir ◽

Representative Study ◽

Beech Stand ◽

Climatic Scenarios ◽

Fagus Sylvatica L ◽

Climate Cooling ◽

The Impact

Abstract This study has been carried out in the Polish Roztoczański National Park and the Ukrainian Ravs’ke Roztochia Regional Landscape Park, both of which are part of the Roztoche region. In each of these two locations, representative study plots were established in beech (Fagus sylvatica L.) stands occupying sites with similar environmental conditions. A longterm prognosis for the dynamics of the chosen beech stands were generated using the computer model FORKOME. The model was used to forecast stand developments for four climatic scenarios (warm-humid, warm-dry, cold-humid, cold-dry) covering a time span of 500 years. Our simulation results indicate that in the control scenario, beech stands were dominating and cyclical changes between beech and Silver fir (Abies alba Mill.) may occur. In the scenarios with assumed climate warming, a decline of fir biomass and an increase of beech biomass, as compared to the control conditions, was noticed. In the scenario with assumed climate cooling, fir biomass increased for the duration of the investigated time span. To conclude, the application of the FORKOME model was found to be a useful tool for analyzing potential scenarios of long-term dynamics of beech stands in the Roztoche region in Poland and Ukraine.

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Demographic variability in spruce-fir-beech forest stands in Europe

10.1101/120675 ◽

2017 ◽

Author(s):

Guillaume Lagarrigues ◽

Franck Jabot ◽

Andreas Zingg ◽

Jean-Claude Gégout ◽

Matija Klopčič ◽

...

Keyword(s):

Forest Dynamics ◽

Abies Alba ◽

Beech Forest ◽

Distribution Area ◽

Distribution Models ◽

Regional Variability ◽

Mixed Stands ◽

Data Set ◽

Demographic Processes

1AbstractMany studies have predicted large changes in forest dynamics during the next century because of global warming. Although empirical approaches and studies based on species distribution models provide valuable information about future changes, they do not take into account biotic interactions and stand-level demographic variations. The objective of this study was to quantify the local and regional variability of the growth and regeneration of three important forest species growing often in mixed stands in Europe (Picea abies (L.) Karst., Abies alba Mill., Fagus sylvatica), and to assess the climatic drivers of this variability. For that purpose, we collected a large forestry data set compiling the long-term (up to 100 years) evolution of species and size distributions for 163 stands across Europe, in the mesic distribution area of these forests. We used an inverse modeling approach, Approximate Bayesian Computation, to calibrate an individual-based model of forest dynamics on these data. Our study revealed that the variability of the demographic processes was of the same order of magnitude between stands of a same forest as between different forests. Out of the three species and two demographic processes studied, only the fir growth strongly varied with temperature. Water availability did not explain any demographic variation over stands. For these forests experiencing mesic conditions, local unmeasured factors seem therefore to have an influence at least as important as macro-environmental factors on demographic variations. Efforts to include these important factors in projection scenarios should therefore be prioritized. Besides, our study demonstrates that inverse modelling methods make possible the analysis of long-term forestry data. Such data should therefore be more widely compiled and used for ecological and global change research.

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Preparation And elemental analysis of ancient fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126846 ◽

1987 ◽

Vol 45 ◽

pp. 410-411

Author(s):

Allen Angel ◽

Kathryn A. Jakes

Keyword(s):

Cross Sections ◽

Physical Structure ◽

Energy Dispersive ◽

Archaeological Sites ◽

X Ray ◽

Long Term Storage ◽

Backscattered Electron ◽

Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

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Examination of moisture content variation within an operational wet deck

TAPPI Journal ◽

10.32964/tj12.1.45 ◽

2013 ◽

Vol 12 (1) ◽

pp. 45-50 ◽

Cited By ~ 4

Author(s):

LAURENCE SCHIMLECK ◽

KIM LOVE-MYERS ◽

JOE SANDERS ◽

HEATH RAYBON ◽

RICHARD DANIELS ◽

...

Keyword(s):

Moisture Content ◽

Southeastern United States ◽

Forest Products ◽

Time Domain Reflectometry ◽

Water Application ◽

Wood Moisture ◽

International Paper ◽

Content Variation ◽

Moisture Variation

Many forest products companies in the southeastern United States store large volumes of roundwood under wet storage. Log quality depends on maintaining a high and constant wood moisture content; however, limited knowledge exists regarding moisture variation within individual logs, and within wet decks as a whole, making it impossible to recommend appropriate water application strategies. To better understand moisture variation within a wet deck, time domain reflectometry (TDR) was used to monitor the moisture variation of 30 southern pine logs over an 11-week period for a wet deck at the International Paper McBean woodyard. Three 125 mm long TDR probes were inserted into each log (before the deck was built) at 3, 4.5, and 7.5 m from the butt. The position of each log within the stack was also recorded. Mixed-effects analysis of variance (ANOVA) was used to examine moisture variation over the study period. Moisture content varied within the log, while position within the stack was generally not significant. The performance of the TDR probes was consistent throughout the study, indicating that they would be suitable for long term (e.g., 12 months) monitoring.

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Improvement Of Curvilinear Diagrams Of Concrete Deformation

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.08.99-104 ◽

2019 ◽

pp. 99-104

Keyword(s):

Reinforced Concrete ◽

Peak Load ◽

Experimental Studies ◽

Concrete Structures ◽

Deformation Model ◽

Reinforced Concrete Structures ◽

Significant Difference ◽

Deformation Diagrams

Problems when calculating reinforced concrete structures based on the concrete deformation under compression diagram, which is presented both in Russian and foreign regulatory documents on the design of concrete and reinforced concrete structures are considered. The correctness of their compliance for all classes of concrete remains very approximate, especially a significant difference occurs when using Euronorm due to the different shape and sizes of the samples. At present, there are no methodical recommendations for determining the ultimate relative deformations of concrete under axial compression and the construction of curvilinear deformation diagrams, which leads to limited experimental data and, as a result, does not make it possible to enter more detailed ultimate strain values into domestic standards. The results of experimental studies to determine the ultimate relative deformations of concrete under compression for different classes of concrete, which allowed to make analytical dependences for the evaluation of the ultimate relative deformations and description of curvilinear deformation diagrams, are presented. The article discusses various options for using the deformation model to assess the stress-strain state of the structure, it is concluded that it is necessary to use not only the finite values of the ultimate deformations, but also their intermediate values. This requires reliable diagrams "s–e” for all classes of concrete. The difficulties of measuring deformations in concrete subjected to peak load, corresponding to the prismatic strength, as well as main cracks that appeared under conditions of long-term step loading are highlighted. Variants of more accurate measurements are proposed. Development and implementation of the new standard GOST "Concretes. Methods for determination of complete diagrams" on the basis of the developed method for obtaining complete diagrams of concrete deformation under compression for the evaluation of ultimate deformability of concrete under compression are necessary.

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