Role of transitory non-structural carbon reserves in boreal forest stand dynamics

国家和国际上对树木死亡和森林衰退的根本机制越来越感兴趣，这些机制最近与干旱和气候变化的强度、持续时间和频率的变化有关。树木死亡的研究主要集中在直接或间接与水分限制有关的过程及其对水分运输的影响。水分限制被认为是切断树叶水分供应的主要原因，导致这些组织干燥，最终导致树木死亡。然而，干旱并不能完全解释树木死亡和森林整体衰退的原因。对这种下降的另一种可能解释是碳(C)饥饿。这一假说表明，由于气孔关闭和C同化减少，树木在高和长时间的胁迫下可能会受到维持其基本呼吸需要所需的C储备不足和耗尽的影响。这一假说还没有经过严格的检验，支持或挑战这一假说的经验数据也很少。

There is growing national and international interest in the underlying mechanisms of tree mortality and forest decline which have recently been associated with changes in the intensity, length and frequency of drought and climate change. Research in tree mortality has mainly focused either directly or indirectly on the processes related to moisture limitations and its impact on water transport. Moisture limitation is thought to be the main driver that cuts off the water supply to the foliage, leading to the desiccation of these tissues and ultimately to the death of trees. However, drought does not fully explain the death of trees and overall forest decline. A possible alternative explanation of this decline is carbon (C) starvation. This hypothesis suggests that due to closed stomata and reduced C assimilation trees could suffer from insufficient and depleted C reserves necessary to maintain their basic respiration needs during high and prolonged stress. This hypothesis has not been rigorously tested and empirical data that support or challenge this hypothesis are scarce.