A simulation study to analyse the relations between crown condition and drought in Switzerland

Abstract Drought stress is assumed to be one of the major factors limiting forest health. This study investigates statistical correlations between site-specific estimations of drought and observed crown defoliation in Switzerland. For this, ecophysiologically based drought indices were computed using the model WAWAHAMO that simulates hydrological and ecophysiological processes in forested ecosystems. Correlation coefficients were calculated for spatial and temporal relationships. No meaningful spatial correlations were found. In the case of temporal relations, significant impacts of drought were detected for all deciduous tree species under consideration, i.e. F. sylvatica , Abies species, F. excelsior , and Quercus species. Weak correlations were found for the coniferous tree species P. abies and no relations were found for the tree species A. alba and P. sylvestris . The limitations of such studies are discussed in view of various aspects.

[1]  J. W. Erisman,et al.  Ten years of monitoring forest condition in Europe; studies on temporal development, spatial distribution and impacts of natural and anthropogenic stress factors , 1997 .

[2]  The rhythm of trees , 1999 .

[3]  P. Jarvis.  The Interpretation of the Variations in Leaf Water Potential and Stomatal Conductance Found in Canopies in the Field , 1976 .

[4]  John L. Innes,et al.  Observations on the Condition of Beech (Fagus sylvatica L.) in Britain in 1990 , 1992 .

[5]  Urs-Beat Brändli,et al.  Schweizerisches Landesforstinventar. Anleitung für die Feldaufnahmen der Erhebung 1993–1995 , 1994 .

[6]  Jan Willem Erisman,et al.  Effects of environmental stress on forest crown condition in Europe. Part I: Hypotheses and approach to the study , 2000 .

[7]  Gilles Boulet,et al.  Stomatal control of transpiration: Examination of Monteith's Formulation of canopy resistance , 1998 .

[8]  Paul J. Kramer,et al.  Plant and soil water relationships: a modern synthesis. , 1969 .

[9]  B. Zierl,et al.  A water balance model to simulate drought in forested ecosystems and its application to the entire forested area in Switzerland , 2001 .

[10]  F. Thomas.  Growth and water relations of four deciduous tree species (Fagus sylvatica L., Quercus petraea [Matt.] Liebl., Q. pubescens Willd., Sorbus aria [L.] Cr.) occurring at Central-European tree-line sites on shallow calcareous soils: physiological reactions of seedlings to severe drought. , 2000 .

[11]  M. Kaennel,et al.  Forest decline and atmospheric deposition effects in the French mountains. , 1995 .

[12]  B. Zierl.  Relations between crown condition and ozone and its dependence on environmental factors. , 2002, Environmental pollution.

[13]  A. Dezetter,et al.  Selection of calibration objective fonctions in the context of rainfall-ronoff modelling in a Sudanese savannah area , 1991 .

[14]  J. Innes.  The impact of climatic extremes on forests: An introduction , 1998 .

[15]  D. Mueller‐Dombois,et al.  Forest Decline in the Atlantic and Pacific Region , 1993, Springer Berlin Heidelberg.

[16]  J. Innes.  Forest Health: Its Assessment and Status , 1993 .

[17]  W. Larcher.  Physiological Plant Ecology , 1977 .

[18]  A. Wellburn,et al.  Air Pollution and Climate Change: The Biological Impact , 1996 .

[19]  Mehdi Homaee,et al.  Root water uptake under non-uniform transient salinity and water stress , 1999 .

[20]  H. Ellenberg,et al.  Vegetation Mitteleuropas mit den Alpen , 1984 .

[21]  J. Santamaría,et al.  Monitoring of the Phytosanitary State of Navarra's Forests, Spain , 1998, Environmental monitoring and assessment.

[22]  V. Dantec,et al.  Interannual and spatial variation in maximum leaf area index of temperate deciduous stands , 2000 .

[23]  Denis Lachance,et al.  Forest Decline Concepts , 1992 .

[24]  Werner Kofler,et al.  Climate-tree-growth relationships of Scots pine stands (Pinus sylvestris L.) exposed to soil dryness , 1998, Trees.

[25]  R. Marrs,et al.  Environmental Ecology: The Impacts of Pollution and Other Stresses on Ecosystem Structure and Function. , 1989 .

[26]  O Kandler,et al.  Air pollution and forest decline in Central Europe. , 1995, Environmental pollution.

[27]  Harald Bugmann,et al.  On the ecology of mountainous forests in a changing climate , 1994 .

[28]  K. Sonesson.  Oak Decline in Southern Sweden , 1999 .

[29]  Svein Solberg,et al.  Changes of forest health in Norwegian boreal forests during 15 years , 2000 .

[30]  G. Landmann,et al.  Role of Climate, Stand Dynamics and Past Management in Forest Declines: A Review of Ten Years of Field Ecology in France , 1993 .

[31]  Radial stem growth of Picea abies in relation to spatial variation in soil moisture conditions , 1996 .

[32]  H. Pruscha,et al.  Der Einfluß von Bestandeskenngrößen, Topographie, Standort und Witterung auf die Entwicklung des Kronenzustandes im Bereich des Forstamtes Rothenbuch , 1996, Forstwissenschaftliches Centralblatt vereinigt mit Tharandter forstliches Jahrbuch.

[33]  L. Walthert,et al.  An analysis of crown condition of Picea, Fagus and Abies in relation to environment in Switzerland , 1996 .

[34]  W. de Vries,et al.  Effects of Environmental Stress on Forest Crown Condition in Europe. Part IV: Statistical Analysis of Relationships , 2000 .

[35]  D. Hertel,et al.  Drought responses at leaf, stem and fine root levels of competitive Fagus sylvatica L. and Quercus petraea (Matt.) Liebl. trees in dry and wet years , 2001 .

[36]  Matthias Dobbertin,et al.  Crown defoliation improves tree mortality models , 2001 .

[37]  L. Kergoat.  A model for hydrological equilibrium of leaf area index on a global scale , 1998 .

[38]  J. Peñuelas,et al.  Effects of a Severe Drought on Water and Nitrogen Use by Quercus ilex and Phyllyrea latifolia , 2000, Biologia Plantarum.