No abstract

We investigated the effects of foliar absorption of dew by eastern white pine (Pinus strobus L.) seedlings on midday shoot water potential, as well as on other water relations variables and growth. Two-year-old container-grown eastern white pine seedlings were subjected to contrasting watering regimes (normal and deficient) and three frequencies of artificial dew (none, once and three times per week) for 10 weeks in a greenhouse. Midday shoot water potential was measured on four occasions during the study. Other water relations variables (relative water content, stomatal conductance, pressure-volume curves) and growth (hypocotyl diameter, aboveground dry mass, root dry mass) were also measured. Artificial dew significantly increased shoot water potential, stomatal conductance and seedling root growth, with greater responses observed for seedlings subjected to a deficient watering regime than for well-watered seedlings. Because dew can be a frequent microclimatic event in some areas, this finding has practical implications for field studies of water relations of eastern white pine and possibly of other coniferous species.Tree Physiology 15, 819--823

The 2030 Agenda calls for a change in thinking in order to implement sustainable development goals (SDGs) and targets as a system. To achieve this goal, the 2030 Agenda established five pillars ("5 Ps"): people, planet, prosperity, peace and partnership. Here, we present a classification of these SDGs and their targets based on the five pillars. Our aim is to improve our understanding of interactions by assessing whether potential synergies and trade-offs are related to the classification of the targets. We surveyed 30 people and asked them to associate the content of target labels with the pillars. We classified SDG and targets according to an original quantification system. We determined whether the interactions were linked to similar or different classifications of the targets. We observed that the more similar the targets were in terms of classification, the more positive the interactions. We also noted that synergies exist between targets of different classifications. Our findings are useful for applying a systemic approach for policy coherence in sustainability analysis.

1 2Black spruce-lichen woodlands are low tree density stands within the 3 closed crown, North American boreal forest that represent a diverging post-fire 4 type of black spruce forest. As natural densification of lichen woodlands has 5 never been observed, plantation remains the only way of shifting these stands to 6 closed canopy stands. The objective of the study was to evaluate site preparation 7 effects on growth and water relations of black spruce (Picea mariana (Mill.) 8 B.S.P.) and jack pine (Pinus banksiana Lamb.) seedlings in black spruce-lichen 9 woodlands (LW), compared to managed black spruce-feathermoss stands 10 (BSFM). Site preparation treatments in LW were no preparation (LWno), patch 11 scarification (LWps), and disk scarification (LWds). The operationally managed 12 BSFM stands stood for the control. Results from the third growing season 13 indicate that soil water availability in intact or lightly prepared patch scarified LW 14 is a limiting variable for seedling growth for both black spruce and jack pine 15 seedlings. However, once LW are prepared with disk scarification, this planting 16 check factor is significantly reduced, to the point of being equal to BSFM in terms 17 of water availability and seedling water relations. The significant seedling growth 18 difference, in favor of BSFM, might be a consequence of the lower level of pre-19 plantation disturbance in LW, compared to BSFM. Our results also suggest that 20 jack pine, through higher water stress tolerance, could constitute a wise 21 silvicultural choice over black spruce, especially with LW established on coarse 22 drought-prone material. 23 3 1

No abstract