Silver fir growth (BAI) in the Pyrenees

The Excel file contains two sheets: 1) silver fir basal area increment from 1960 to 2000 in different populations across the Pyrenees; 2) silver fir growth (mean BAI), growth trend (BAI trend), Resistance index (Rt), Recovery index (Rc) and Resilience index (Rs) in different populations across the Pyrenees. In addition, we provide several explanatory variables describing topographic and stand characteristics that were used to explain the variation in the above mentioned variables

Changes in plant taxonomic and functional diversity patterns following treeline advances in the South Urals

<p><b><i>Background</i></b>: Treeline ecotones represent environmental boundaries that fluctuate in space and time and thus induce changes in plant taxonomic and functional diversity.</p> <p><b><i>Aims</i></b>: To study changes through time in taxonomic and functional plant diversity patterns along the treeline ecotone.</p> <p><b><i>Methods</i></b>: In 2002, vegetation was sampled along a gradient from upper montane forest to the treeline–alpine transition in the South Ural Mountains, Russia. In 2014, vegetation was resampled and plant functional traits were collected. We studied spatial and temporal changes in plant species composition, functional composition and functional diversity.</p> <p><b><i>Results</i></b>: Species composition and diversity changed along the elevational gradient. The functional composition in height, leaf area, specific leaf area and leaf nitrogen content decreased with elevation, whereas functional composition of leaf carbon content increased. We found a temporal shift towards shorter plants with smaller leaves in treeline sites. Functional richness varied in several traits along the elevational gradient, while functional dispersion showed a trend towards increased functional dispersion in height, specific leaf area and leaf nitrogen in the treeline–tundra transition.</p> <p><b><i>Conclusions</i></b>: Tree encroachment across the treeline ecotone has resulted in a shift in plant species relative abundances and functional diversity, possibly affecting plant community assembly patterns.</p

Relationship between basal area increment and soil water balance during the most influential period for growth.

<p>Basal area increments (means ± 1SE) residuals and seasonal water balances (those selected as the most influential for tree growth during the current year; see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0073855#pone-0073855-t004" target="_blank">Table 4</a>) 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).</p

Basal-area increment patterns for the seven tree species from a Bolivian tropical dry forest.

<p>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 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0073855#pone-0073855-t003" target="_blank">Table 3</a>.</p

Views of the Bolivian Chiquitano tropical dry forest during the dry season.

<p>The inset shows the location of the study site (circle) within Bolivia (green areas correspond to forests).</p

Characteristics of trees and species sampled in a Bolivian tropical dry forest.

<p>Values are means ± 1SE. Means sharing a letter were not significantly different using paired Mann-Whitney <i>U</i> tests (<i>P</i>≤0.05).</p

Statistics of the best linear mixed-effects models fitted to basal area increment as a function of soil water balance.

<p>Abbreviations: LD, late dry season; EW, early wet season; W, wet season; LW, late wet season; ED, early dry season; D, dry season. Note the relative probability that the selected model is the best one (<i>Wi</i>) and the basal area increment variance (R²) explained by the models. Bold coefficients are significant (<i>P</i>≤0.05). Means sharing a letter were not significantly different using paired Mann-Whitney <i>U</i> tests.</p

Wood cross-sections with distinct annual rings of studied tree species.

<p>The white triangles mark the annual boundaries corresponding to marginal parenchyma. In the rings the growth direction is from left (pith) to right (bark).</p

Climatic conditions of the study area.

<p>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.</p

Wood density is negatively related to growth variability driven by water balance.

<p>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 <i>y</i> axis (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0073855#pone-0073855-t004" target="_blank">Table 4</a>).</p