DendroSync: An R package to unravel synchrony patterns in tree-ring networks

Abstract Spatial synchrony refers to the presence of a common signal for a time-varying characteristic that, in dendrosciences, is shared among tree-ring chronologies from a particular area. Analysis and interpretation of synchrony patterns in tree-ring networks is currently limited by: (i) the requirement for flexible modelling of complex correlations and heteroscedastic errors and (ii) the availability of ready-to-use open software to fulfil this task. We present an R package (DendroSync) that facilitates estimating and plotting synchrony patterns for pre-defined groups. The package has been devised to work with traits derived from tree rings (e.g. ring-width), but other data types are also suitable. It combines variance-covariance mixed modelling with functions that quantify the degree to which tree-ring chronologies contain a common signal over a fixed time period. It also estimates temporal changes in synchrony using a moving window algorithm. The functionality and usage of DendroSync are illustrated using a simple example.

[1]  D. Frank,et al.  Characterization and climate response patterns of a high-elevation, multi-species tree-ring network in the European Alps , 2005 .

[2]  Bruce P. Finney,et al.  Reduced growth of Alaskan white spruce in the twentieth century from temperature-induced drought stress , 2000, Nature.

[3]  E. Gutiérrez,et al.  Unravelling spatiotemporal tree-ring signals in Mediterranean oaks: a variance-covariance modelling approach of carbon and oxygen isotope ratios. , 2014, Tree physiology.

[4]  C. Ginzler,et al.  Spatial diversity of recent trends in Mediterranean tree growth , 2014 .

[5]  Fritz H. Schweingruber,et al.  Tree-ring width and density data around the Northern Hemisphere: Part 1, local and regional climate signals , 2002 .

[6]  F. Biondi,et al.  Bioclimatology of beech (Fagus sylvatica L.) in the Eastern Alps: spatial and altitudinal climatic signals identified through a tree‐ring network , 2007 .

[7]  J. Camarero,et al.  Climate increases regional tree‐growth variability in Iberian pine forests , 2007 .

[8]  J. Friedman.  A VARIABLE SPAN SMOOTHER , 1984 .

[9]  R Core Team,et al.  R: A language and environment for statistical computing. , 2014 .

[10]  Benjamin Poulter,et al.  Improved tree-ring archives will support earth-system science , 2017, Nature Ecology &Evolution.

[11]  C. Rolland.  Decreasing teleconnections with inter-site distance in monthly climatic data and tree-ring width networks in a mountainous Alpine area , 2002 .

[12]  K. Briffa,et al.  Trends in recent temperature and radial tree growth spanning 2000 years across northwest Eurasia , 2008, Philosophical Transactions of the Royal Society B: Biological Sciences.

[13]  R. Jennrich,et al.  Unbalanced repeated-measures models with structured covariance matrices. , 1986, Biometrics.

[14]  V. Trouet,et al.  A pan-European summer teleconnection mode recorded by a new temperature reconstruction from the northeastern Mediterranean (ad 1768–2008) , 2012 .

[15]  Scott St. George,et al.  An overview of tree-ring width records across the Northern Hemisphere , 2014 .

[16]  Frédéric Guichard,et al.  Synchrony: quantifying variability in space and time , 2014 .

[17]  H. Fritts,et al.  Tree Rings and Climate. , 1978 .

[18]  A. Raftery.  Approximate Bayes factors and accounting for model uncertainty in generalised linear models , 1996 .

[19]  David L. Peterson,et al.  MOUNTAIN HEMLOCK GROWTH RESPONDS TO CLIMATIC VARIABILITY AT ANNUAL AND DECADAL TIME SCALES , 2001 .

[20]  Kevin T. Smith,et al.  Plasticity in Dendroclimatic Response across the Distribution Range of Aleppo Pine (Pinus halepensis) , 2013, PloS one.

[21]  R. Sánchez‐Salguero,et al.  Forests synchronize their growth in contrasting Eurasian regions in response to climate warming , 2016, Proceedings of the National Academy of Sciences.

[22]  J. Camarero,et al.  Increasing Aridity is Enhancing Silver Fir Abies Alba Mill.) Water Stress in its South-Western Distribution Limit , 2006 .

[23]  Hadley Wickham,et al.  ggplot2 - Elegant Graphics for Data Analysis (2nd Edition) , 2017 .

[24]  David R. Anderson,et al.  Model selection and multimodel inference : a practical information-theoretic approach , 2003 .

[25]  J. Camarero,et al.  Increasing drought effects on five European pines modulate Δ13C-growth coupling along a Mediterranean altitudinal gradient , 2017 .

[26]  Philippe Ciais,et al.  Site‐ and species‐specific responses of forest growth to climate across the European continent , 2013 .