Bugmann Harald

Totholz in Schweizer Fichtenwaldreservaten

Project Number: CH-5530
Project Type: Research_Project
Project Duration: 06/01/2015 - 12/31/2015
Funding Source: ETH ,
Project Leader: Prof. Harald Bugmann
Institut für Terrestrische Ökosysteme (ITES)
ETH Zürich
ETH Zentrum CHN G 76.1
Universitätstrasse 16
8092 Zürich
Phone: +41 (0) 44 632 32 39 ; +41 (0) 44 632 32 17
FAX: +41 (0) 44 632 13 58
e-Mail: harald.bugmann(at)env.ethz.ch

related to this project.
for which the project has a relevance.

Research Areas:

forestry and agricultural sciences

Final abstracht

Dead wood of high quantities, different dimensions and decay stages provides a key habitat for a variety of forest species (e.g. fungi, lichens, bryophytes or beetles) and is acknowledged as a good indicator for a forest’s naturalness. This master thesis focuses on the lying dead wood component. The purpose was to investigate for the first time the dead wood dynamic in seven Swiss mountainous Norway spruce (Picea abies) dominated forest reserves in a permanent plot inventory and to provide a first reference for the governmental biodiversity strategy in managed stands. Therefore, lying dead wood quantity and quality was assessed in field and statistically related to site, stand and climate conditions, past disturbances and former management regime. Furthermore, the spatial pattern of dead wood with respect to orientation and distribution was analyzed.
The investigated forest reserves featured on average lying dead wood volumes of 80 ± 23 m3/ha, generally consisting of large dimensions and advanced decomposition stages, two quality features particularly important for saproxylic species. Statistical modeling by several environmental factors was limited to 24 investigated permanent plots only and the effect of the examined factors could only be partly understood. More study plots might alleviate this problem. Concerning spatial pattern analysis, hillside orientation, slope inclination and past wind disturbances were main drivers influencing the falling direction of logs. The results of spatial pattern analysis largely confirm that the spatial pattern of standing trees directly influences the spatial pattern of logs and that the stand age affects the spatial clustered or random distribution of dead wood.
The found values of dead wood quantity and quality are comparable to other coniferous forest reserves across Europe. Nevertheless, traces of former management are still partly visible, particularly in the diameter and spatial distribution of dead wood. The analyses suggest that the governmental biodiversity strategy well aims the implementation of a continuous temporal and spatial distribution of dead wood, but the targeted volumes are only partly sufficient to preserve the forest biodiversity. Moreover, important quality features such as for example large dimensions are not included in the biodiversity strategy.

Leading questions:
Totholz ist für die Biodiversität eine bedeutende Ressource. Wie viel liegendes Totholz gibt es in Schweizer Fichtenwaldreservaten, in welcher Dimension und Qualität? Was sind die bestimmenden Faktoren dafür (Entwicklungsstufe, Grundfläche, Baumartenzusammensetzung, Störungseinflüsse)? Zur Beantwortung werden in 20-25 Kernflächen in Schweizer Fichtenwaldreservaten alle liegenden Totholzstücke vermessen (Vollerhebung) und deren Zersetzungsgrad bestimmt. Die Daten zur Struktur der lebenden Bestände werden den Langzeitdaten der Reservatsforschung entnommen. Die Fragen werden mit statistischen Modellen beantwortet.
Der Bezug zum SNP liegt darin, dass 2-4 der 20-25 Kernflächen aus dem SNP stammen. Bisher fehlen Daten zu Totholzquantität und –qualität aus dem SNP weitgehend. Das Projekt wird diese Lücke für Fichtenwälder im SNP schliessen und erlaubt es, Totholzquantität und –qualität im SNP mit anderen Wäldern der Schweiz zu vergleichen

Rimle, A. (2016) Quantity and quality of coarse woody debris in mountainous Norway spruce forest reserves in Switzerland. Master thesis at the Chair of Forest Ecology, Department of Environmental Systems Sciences, ETH Zurich, and at the Research Unit Forest Resources and Forest Management, WSL Birmensdorf. 87 p.

Last update: 3/20/17
Source of data: ProClim- Research InfoSystem (1993-2020)
Update the data of project: CH-5530

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