Table 1 Summary of the fitted linear mixed model of resilience, resistance and recovery.

From: Low growth resilience to drought is related to future mortality risk in trees

 

Std. β

CI

df

t/χ2

P

Resilience

  Fixed effects

    (Intercept)

−0.062

−0.121, −0.004

72.9

−2.00

0.049

    Surviving

−0.091

−0.142, −0.037

2623.9

−3.43

0.001

    DBHi

−0.001

−0.001, 0.000

2536.1

−4.04

<0.001

    Δtime

0.001

0.000, 0.002

1920

2.48

0.013

    Aridity

0.011

−0.056, 0.076

36.7

0.28

0.783

    Soil fertility

−0.002

−0.011, 0.008

26.7

−0.39

0.698

    Surviving × Δtime

0.001

0.000, 0.002

3008.7

2.83

0.005

    Surviving × aridity

0.063

0.027, 0.097

3143.6

3.51

<0.001

    Surviving × soil fertility

−0.015

−0.021, −0.008

2679.8

−4.63

<0.001

 Random effects

   Genus (species (site))

  

3

739

<0.001

  No. of trees/sites/species/genus

3207/104/21/10

  R2m/R2c/ΔAIC

0.06/0.3/22.2

Resistance

  Fixed effects

    (Intercept)

−0.207

−0.317, −0.077

36.9

−3.41

0.002

    Surviving

0.026

−0.009, 0.061

3557.8

1.47

0.143

    Gymnosperms

0.017

−0.066, 0.100

19.7

0.37

0.714

    Aridity

0.037

−0.102, 0.146

34.3

0.63

0.531

    Soil fertility

0.016

0.001, 0.036

28.6

2.16

0.039

    Surviving × gymnosperms

−0.035

−0.061, −0.009

3551.6

−2.66

0.008

    Surviving × aridity

0.028

−0.008, 0.065

3565.1

1.52

0.129

 Random effects

   Genus (species (site))

  

3

1293

<0.001

  No. of trees/sites/species/genus

3660/118/22/10

 R2m/R2c/ΔAIC

0.04/0.47/18.3

Recovery

  Fixed effects

    (Intercept)

0.141

0.066, 0.216

29.4

3.56

0.001

    Surviving

−0.022

−0.047, 0.002

3623.8

−1.78

0.074

    Gymnosperms

−0.025

−0.109, 0.059

22.1

−0.56

0.578

    Soil fertility

−0.016

−0.031, −0.003

34.4

−2.40

0.022

    Surviving × gymnosperms

0.037

0.0100, 0.065

3628.1

2.65

0.008

    Surviving × soil fertility

−0.006

−0.011, 0.000

3637.4

−2.07

0.039

 Random effects

   Genus (species (site))

  

3

1092

<0.001

  No. of trees/sites/species/genus

3733/118/22/10

  R2m/R2c/ΔAIC

0.04/0.42/4.6

  1. The response variables are log-transformed resistance, recovery and resilience computed for tree-ring width (TRW) data, assuming a Gaussian error distribution with an identity link. The fixed part of the model included status (now-dead or surviving), taxonomic group (angiosperm or gymnosperm), diameter at breast height (DBHi, cm), time period between drought event and last year recorded in each individual tree ring-width series (Δtime, years), average ratio between precipitation and potential evapotranspiration (aridity) for the period 1970–2000, a measure of soil fertility, and interactions between status and other fixed effects. The random part of the model included site nested within species nested within genus. The intercept corresponds to the reference status (now-dead) and taxonomic group (angiosperms). This summary corresponds to the reduced model (the full model is presented in Supplementary Table 1; for model selection, see Supplementary Table 2). Values represent the standardised estimates of regression coefficients (std. β), 95% confidence intervals (CIs), the t statistic or χ2 statistic and the associated P value of significance (bold type for significant fixed effects, P < 0.05). Estimates of regression coefficients for the intercept were not standardised. The signs indicate the direction of the effects. R2m is the marginal R2, R2c is the conditional R2, ΔAIC is the increment on AIC values with respect to that of the model without status (Supplementary Table 2). The low marginal R2 explained by the fixed effects of the reduced models might be a consequence of data heterogeneity, with high variation within species and sites22. Nevertheless, differences between statuses were detected, and smaller AICs and larger differences (ΔAIC) > 2.0 related to models without status indicate that models including status showed higher explanatory power69
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