Figure 1.
Views of the Bolivian Chiquitano tropical dry forest during the dry season.
The inset shows the location of the study site (circle) within Bolivia (green areas correspond to forests).
Figure 2.
Climatic conditions of the study area.
Data from a nearby Concepción meteorological station (A), and estimated monthly water balance (B). The previous (dashed line) and current (continuous line) growth years correspond to the years when the tree ring formation started and ended, respectively. Abbreviations: LD, late dry season; EW, early wet season; W, wet season; LW, late wet season; ED, early dry season; D, dry season. Values of water balance are means ± 1SE.
Table 1.
Characteristics of the seven tree species studied in the INPA site, a tropical dry forest located in the Chiquitana region of Bolivia.
Table 2.
Characteristics of trees and species sampled in a Bolivian tropical dry forest.
Figure 3.
Wood cross-sections with distinct annual rings of studied tree species.
The white triangles mark the annual boundaries corresponding to marginal parenchyma. In the rings the growth direction is from left (pith) to right (bark).
Figure 4.
Basal-area increment patterns for the seven tree species from a Bolivian tropical dry forest.
Basal area increments (means ± 1SE) are displayed as a function of tree age (A, C, E, G, I, K, M) and calendar year (B, D, F, H, J, L, N). See also the comparisons among tree species displayed in Table 3.
Table 3.
Growth-related characteristics of the seven tree species studied in a Bolivian tropical dry forest.
Figure 5.
Relationship between basal area increment and soil water balance during the most influential period for growth.
Basal area increments (means ± 1SE) residuals and seasonal water balances (those selected as the most influential for tree growth during the current year; see Table 4) are displayed as black and blue lines, respectively. The soil water balance was calculated as the difference between the precipitation (P) and the potential evapotranspiration (PET).
Table 4.
Statistics of the best linear mixed-effects models fitted to basal area increment as a function of soil water balance.
Figure 6.
Wood density is negatively related to growth variability driven by water balance.
The amount of basal area increment variance (R2) explained by the best linear mixed-effects models fitted as a function of soil water balance is shown in the y axis (see Table 4).