Daily weather response of balsam fir (Abies balsamea (L.) Mill.) stem radius increment from dendrometer analysis in the boreal forests of Qu�bec (Canada)

Abstract

Daily stem radial growth of balsam fir [Abies balsamea (L.) Mill.] was studied between 1998 and 2001 using automated point dendrometers to investigate meteorological influence. By dividing the dendrometer daynight variation, the diurnal growth pattern was resolved into the three phases of (1) contraction, (2) expansion and (3) stem radius increment (SRI). The entire circadian cycle (4) defined by the three previous phases was considered as a fourth phase. The mean weather conditions of each phase were compared with the SRI using simple correlation and response function analysis. It was found that the weather conditions prevailing from 1600/ 1700 hours to 0800/0900 hours corresponding with the expansion-SRI phases had greater impact on SRI. Response function results confirmed most of the correlation analyses and explained up to 95% of the variance of the SRI series. Total rainfall in phases 2, 3 and 4 was correlated positively with SRI, and hence verifies the importance of daily water balance. The importance of water was also demonstrated by the negative effect of high vapour pressure deficit of phase 2, decreasing the possibility of cell radial expansion. The maximum temperature of phase 3 was the only temperature variable having a positive impact on SRI suggesting that night temperature was more important than day temperature in controlling radial growth. These results may influence the process of cell enlargement and reflect only the mechanical aspect of growth.

Environmental correlates of stem radius change in the endangered Fitzroya cupressoides forests of southern Chile

“…172 The approximate location of the three major physiographic units in the area is shown (Coastal 179 minimum to the next morning maximum. Stem radius increment (ΔR or phase 3) corresponds tothe portion of the expansion phase from the time the stem radius surpasses the morning 234 maximum until the following maximum, and has been considered as an estimate of growth 235 (Deslauriers et al, 2003, Deslauriers et al, 2007a. When the previous cycle maximum was 236 reached a positive stem radius change (ΔR +) was calculated.…”

“…To make variables independent from each 265 other and avoid using non-stationary data in the correlation analyses, the first difference was 266 used for contraction and for all the climate variables, except precipitation. Mean correlationswere significant if after 1000 bootstrapped iterations their absolute values were at least two times 268 their standard deviations (SD) (Deslauriers et al, 2003). Data for the two estimated growing 269 seasons (2011)(2012)(2012)(2013) were used.…”

“…Since VPD is derived from and strongly related to air humidity, relationships between these 434 variables and stem radius change were usually similar in magnitude, but in opposite directions. Finally, since prevailing weather conditions mostly during the expansion phase have been shown 496 to affect tree radial increment (Deslauriers et al, 2003), correlations were performed between 497 environmental conditions during this phase and stem increment. This was done just using regular 498 cycles to minimize the effect of large differences in duration between phases.…”

Analyse intra-annuelle des fluctuations radiales des tiges et des racines adventives de l'épinette noire (Picea mariana (Mill. B.S.P.) /

“…Les mesures obtenues avec les dendromètres furent reliées à la physiologie des arbres de plusieurs façons. Elles ont surtout été utilisées pour documenter la croissance secondaire durant la saison active et inférer le moment du début de la croissance (Korstian, 1921;Pearson, 1924;Daubenmire and Deters, 1947;Daubenmire, 1949Daubenmire, ,1950Belyea et al, 1951;Jackson, 1952;Kozlowski and Winget, 1964;Braekke and Kozlowski, 1975;Tardif et al, 2001;Deslauriers et al, 2003b, Rossi et al, 2006, ou encore pour l'étude des phénomènes hydriques prenant place chez les plantes (Zahner et al, 1964;Molz and Klepper, 1973;Milne et al, 1983;Hergoz et al, 1995;Downes et al, 1999;Zweifel, 1999;). …”

Crescimento e eficiência no uso da água por clones de eucalipto sob doses de potássio

“…O alongamento celular é basicamente dependente da água, porque a pressão de turgor leva à expansão celular irreversível (PROSEUS; BOYER, 2005), e o alongamento celular pode ser considerado a mais importante força causadora do crescimento radial diário líquido (DESLAURIERS et al, 2003). No caso desse trabalho, a maior correlação do incremento cambial com a umidade relativa do ar pode estar relacionada à baixa taxa de transpiração causada pela maior umidade relativa e aquela reduz a pressão negativa no sistema de condução e aumenta o turgor nas células cambiais do tronco, assim favorecendo a divisão e expansão celular (KÖCHER et al, 2012 A interação entre clone e potássio ocorreu entre os dias 29 de junho e 2 de julho para o clone AEC 042.…”