Multiple environmental control of leaf area and its significance for productivity in beech saplings

Abstract

Climatic change exposes temperate trees to the simultaneous alteration of various growth-relevant factors, among them increased temperatures, extended growing season length and rising atmospheric [CO 2 ], often in combination with more severe droughts and reduced air humidities in summer, and elevated atmospheric N deposition. We conducted a multi-factorial climate chamber experiment to search for interactive effects of temperature (T), soil moisture (h), water vapour saturation deficit (VPD) and N availability (N) on the growth of Fagus sylvatica saplings and for identifying the most relevant factors that control leaf area development and productivity under a future warmer and drier climate with continuing high N deposition. For each of the four factors, two levels were simulated, reflecting current and expected future conditions in Central European beech forests. All four factors (including VPD) had a significant effect on productivity; several factors (e.g. T 9 VPD) interacted in a synergistic way. Productivity was most tightly correlated with the number of leaves while leaf area was less influential and photosynthetic activity was of only minor importance. The number of leaves produced was most tightly correlated with h, N and VPD, while leaf area (leaf expansion) showed closest relation to temperature. We conclude that predictions about the growth response of trees to climate change and altered atmospheric N deposition need to consider a multitude of environmental factors and must account for positive and negative factor interactions.

Phenological and physiological evaluation of first and second cropping periods of sorghum and maize crops

“…Although leaf area of sorghum plants was lower under the second cropping conditions, this parameter was almost constant from the beginning to the end of the phenological stages, which may be associated with the ability of sorghum plants to stay green , ensuring photosynthesis in the leaves under conditions of water shortage (Borrell et al, ). More limiting resource conditions promote the reduction in leaf area, as well as the genetic aspects of the plant itself (Fender, Mantilla‐Contreras, & Leuschner, ). Factors such as soil and air temperature and especially soil moisture are determinant in leaf expansion.…”

“…For sorghum, there is also sensitivity to the photoperiod, which leads to decreases in plant height (Wolabu & Tadege, 2016 (Borrell et al, 2014). More limiting resource conditions promote the reduction in leaf area, as well as the genetic aspects of the plant itself (Fender, Mantilla-Contreras, & Leuschner, 2011). Factors such as soil and air temperature and especially soil moisture are determinant in leaf expansion.…”

Biomass allocation to roots and shoots is more sensitive to shade and drought in European beech than in Norway spruce seedlings

“…soil water or nutrients. This means that interactions between resources need to be taken into account (Fender et al, 2011). In fact Madsen (1994) and Löf et al (2005) showed, for European beech, that the growth response of the seedlings to increased light availability and biomass partitioning were strongly dependent on soil moisture status.…”

Elevated air humidity modulates bud size and the frequency of bud break in fast-growing deciduous trees: silver birch (Betula pendula Roth.) and hybrid aspen (Populus tremula L. × P. tremuloides Michx.)

“…Increased humidity is generally favorable for tree growth (e.g., Lendzion and Leuschner 2008;Fender et al 2011), presumably due to increased photosynthetic rates. However, little effect or even negative impacts of increased humidity have also been reported, indicating that enhanced gas exchange and elevated photosynthetic rates do not necessarily translate into improved growth (Cunningham 2006 and references therein).…”