Hydraulic traits are coordinated with maximum plant height at the global scale

Abstract

Coordination between plant height and xylem traits is aligned with habitat aridity across the Earth’s terrestrial biomes.

Different ways to die in a changing world: Consequences of climate change for tree species performance and survival through an ecophysiological perspective

“…Although tree mortality under drought conditions can be triggered by a combination of different effects (Adams et al, 2017;Hartmann et al, 2018;Kono et al, 2018), the impact of such effects can vary significantly depending on the phenological stage and size of the plant (Liu et al, 2019;Olson et al, 2018). As trees grow taller, the distance to move water from roots to leaves gets longer, which increases the resistance along the pathway (Ambrose, Sillett, & Dawson, 2009;Fajardo, McIntire, & Olson, 2019), resulting in an increase in the tension inside xylem vessels and in the risk of HF under drought conditions (Bennett et al, 2015;Fajardo et al, 2019).…”

Land–atmosphere interactions in the tropics – a review

“…However, some recent work demonstrates that existing satellite observations, especially solar-induced fluorescence (SIF), may be leveraged to remotely assess surface turbulent fluxes in the tropics. In contrast to the normalized difference vegetation index (NDVI) or many other vegetation indices which are indirect byproducts of photosynthesis (Morton et al, 2014), SIF (at the leaf scale) is directly related to the ecosystem-scale photosynthesis rate, providing important information on the impact of stressors on photosynthesis, and is available from existing remote-sensing platforms (Frankenberg et al, 2011(Frankenberg et al, , 2012Joiner et al, 2011Joiner et al, , 2013Guanter et al, 2014;Lee et al, 2015;Duveiller and Cescatti, 2016;Liu et al, 2017;Thum et al, 2017;Norton et al, 2018). SIF is thus an important indicator of the rates of photosynthesis and transpiration through stomatal (small pores at the leaf surface) regulation Pagán et al, 2019).…”

“…Leaf and xylem water status are regulated by the relative demand of sap from transpiration, which depends on leaf VPD. It also depends on sap supply to the leaves, the rate of which is controlled by the xylem conductivity and which is high for tall tropical rainforest trees (Liu et al, 2019). This conductivity is reduced by cavitation in the xylem (formulation of air bubbles blocking the ascent of sap flow from the roots to the leaves; Martinez-Vilalta et al, 2014; Martinez-Vilalta and Garcia-Forner, 2016).…”

“…In tall-canopy species the flow in the xylem from the roots may be limited, as the xylem hydraulic conductivity is inversely proportional to height, though this is partially compensated by more efficient xylem (higher specific conductivity; Liu et al, 2019). However, higher evaporative demand in the dry season and/or under anomalously dry conditions can only be partially be mitigated by the more efficient xylem and by the plant internal storage; stomatal shutdown may therefore be inevitable in avoiding desiccation and xylem cavitation ( Fig.…”

Wood structure and function change with maturity: Age of the vascular cambium is associated with xylem changes in current‐year growth

“…Plant evolutionary ecologists spend their time searching for the causal mechanisms responsible for patterns in the green world. For example, plant hydraulics provide a host of patterns to be explained, such as the pervasive tendency for maximum vessel diameter to be narrower in drier areas (Pfautsch et al, 2016), the striking tendency for vessels to be solitary when the ground tissue is made up of true tracheids (Rosell et al, 2007), and the potential tradeoff between vessel diameter and resistance to droughtinduced embolism (Liu et al, 2019). Students of plant hydraulics actively debate the causes, or even the reality, of all of these and many other patterns Rico et al, 2013;Rodriguez-Zaccaro et al, 2019).…”