Fig 1.
Study Locations.
Table 1.
Study sites details.
Table 2.
Measurement details by site.
Fig 2.
Schematic diagram illustrating metrics of tree circumference change.
Shown are the most commonly observed pattern of dynamics in tree circumference change (Δc) and how these are analyzed to calculate daily circumference increment (I), residual variation (Δcr), and daily amplitude (A).
Fig 3.
Example record illustrating patterns of tree circumference dynamics that align with physiological expectations.
(a) Change in circumference relative to the start of the measurement record (Δc; solid line) and sap flow (SF; dashed line) measured on a 70 cm DBH Liriodendron tulipifera at SCBI; (b) band temperature (Tband; black line), solar radiation (Rad; grey line), and precipitation (PPT; vertical black lines).
Fig 4.
Average daily patterns in stem circumference relative to other variables.
Average daily patterns in Δcr, sap flow (SF; averaged by genus) or evapotranspiration (ET), temperature (Tband), and radiation (Rad) on non-rain days during analysis period from the four study sites. For Δcr, line type indicates size class, and lines are colored by genus as indicated in the legends. Tband is plotted as solid line, Rad as bars.
Fig 5.
Daily patterns of tree circumference change in relation to temperature.
(a) Diagram showing mean phase angle θ for all trees (circles: live trees; triangles: dead trees), where π/2 < θ < 3π/2 indicates shrinkage and θ < π/2 or θ > 3π/2 indicates swelling; (b) Histograms of mean coherence (colored bars) and proportion of days with coherence greater than 70% (hatched bars); (c) examples of daily (as opposed to mean) phase angles (θday) for individual trees, corresponding to larger symbols in (a). Examples include a tree with shrinkage on ≥75% of days (Liriodendron tulipifera, DBH = 49.3 cm, SCBI), one with swelling ≥75% of days (Liriodendron tulipifera, DBH = 69.3, SERC), and one with no consistent pattern (Hura crepitans, DBH = 67.1 cm, BCI). For all 3 panels site-colors correspondences are given in (b).
Table 3.
Numbers and mean daily amplitude (A) of ADBs exhibiting daily shrinkage, expansion, or no dominant pattern.
Table 4.
Mixed model results for correlations between A (of trees with shrinkage on ≥75% of days) and scaled daily values of climatic and biomicrometeorological variables.
Fig 6.
Example responses of trees at each of the four study sites to rain events.
Vertical dashed grey lines are rainy days and vertical solid black lines are precipitation amounts. Each colored line represent one tree, with species and DBH (cm) indicated in legends. Trees were selected for relatively strong rain responses and good data records over a 40-day time period selected to focus on rain events.
Table 5.
Mixed model results for rain effect on I.