1

Fig. 1. Crossdated time series of tree-ring width of hybrid poplar in Auce (AUC) (A) and Šķēde (SKD) (B) sites in the western part of Latvia (thick lines represent mean values), crossdated time series of hybrid aspen (C) from Kalsnava (KLN) site in the eastern part of Latvia, residual chronologies of tree-ring width (D) and sample depth of the datasets (E).

Table 1. Statistics of crossdated datasets of tree-ring width (TRW) of hybrid poplar and hybrid aspen in stands near Auce (AUC), Šķēde (SKD) and Kalsnava (KLN).
  Hybrid poplar Hybrid aspen
AUC SKD KLN
Covered period 1954–2013 1949–2013 1965–2013
Number of crossdated trees 12 10 21
Min. TRW, mm 0.12 0.09 0.14
Max. TRW, mm 11.19 12.01 15.74
Mean TRW, mm 2.88 2.86 4.01
Standard deviation, mm 1.86 0.92 2.28
Mean sensitivity 0.42 0.40 0.35
Mean interseries correlation 0.51 0.42 0.51
Autocorrelation 0.56 0.74 0.69
Expressed population signal 0.92 0.86 0.95
Gleichläufigkeit 0.69 0.68 0.70
Signal to noise ratio 10.77 6.17 19.74
2

Fig. 2. Significant Pearson correlation coefficients (black bars) between climatic factors and residual chronologies of the TRW of hybrid poplar in Auce (AUC) (A) and Šķēde (SKD) (B) sites in the western part of Latvia and the residual chronology of hybrid aspen at the Kalsnava (KLN) site in the eastern part of Latvia (C). Collinear factors have been omitted. PET-potential evapotranspiration.