Bigler Christof

Predicting growth-dependent tree mortality
Voraussagen zur wachstumsbedingte Mortalität von Bäumen


Project Number: SNF 140968
Project Type: Dissertation
Project Duration: 10/01/2010 - 06/30/2016 project completed
Funding Source: other , SNSF ,
Project Leader: Prof. Christof Bigler
Forest Ecology
Dept. Umweltsystemwissenschaften (D-USYS)
ETH Zürich
CHN G77
Universitätstrasse 22
8092 Zürich
Phone: +41 (0) 44 632 52 05
e-Mail: christof.bigler(at)env.ethz.ch
http://www.usys.ethz.ch/

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

Disciplines:
forestry

Keywords:
Tree mortality, mortality models, forest succession, stone pine, European larch

Abstract:
Tree mortality as a crucial element of natural forest dynamics is still a poorly understood process. Abrupt growth decreases are known to occur several years or decades before complete cessation of growth. Hence, identifying and linking these growth decreases to potential inciting factors such as drought and frost will improve our understanding of mortality processes. We analyzed nine Central European tree species including six coniferous species (Abies alba, Picea abies, Larix decidua, Pinus sylvestris, Pinus cembra, Pinus montana) and three broadleaved species (Fagus sylvatica, Quercus spp., Acer pseudoplatanus). Treering data from 848 standing dead trees from 14 forest reserves all over Switzerland were sampled. We applied distributed lag non-linear models to relate abrupt growth decreases to drought and frost. The results indicate for many species that both drought and frost have a moderate to major impact on abrupt growth decreases prior to tree death. While late frost in spring may instantaneously result in sustained abrupt growth decreases in most species except Scots pine and mountain pine, severe drought over several months in spring may either show an immediate negative impact on growth, such as in beech, or feature negative reactions that are lagged by several years, such as in oak and Scots pine. Thus, extreme climatic conditions have an essential influence on abrupt growth decreases that finally result in tree death, although variability of the reactions within and among species is high. 2016 Elsevier B.V. All rights reserved.

Leading questions:
Das Ziel dieser Studie ist, für die häufigsten Baumarten der Schweiz und Zentraleuropas sowohl ein besseres Verständnis über die Mortalitätsprozesse zu erhalten als auch die wichtigsten Auslöser von Mortalität an verschiedenen Standorten zu identifizieren. Die folgenden Forschungsfragen stellen sich dabei: – Welche Variablen (z.B. absoluter/relativer jährlicher Zuwachs, Durchmesserklasse, Standortseigenschaften) zeigen einen Zusammenhang mit Mortalität der verschiedenen Baumarten auf unterschiedlichen Standorten? – In welchem Ausmass sind klimatische Extremereignisse für episodische Absterbemuster verantwortlich? – Inwiefern unterscheiden sich die Wachstums-Mortalitätsbeziehungen der wichtigsten europäischen Hauptbaumarten auf unterschiedlichen Standorten?

URL: http://p3.snf.ch/Project-140968

Publications:
Übersicht Publikationen




Last update: 5/24/19
Source of data: ProClim- Research InfoSystem (1993-2024)
Update the data of project: CH-5151

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