Vapour Pressure Deficit Modulates Hydraulic Function and Structure of Tropical Rainforests Under Non-Limiting Soil Water Supply

Tropical rainforests play a powerful role in mediating the global climate through the exchange and storage of carbon and water. Climate change is expected to generate higher atmospheric water demand in many areas, potentially increasing the rate of evaporation. In this study, we show that higher evaporative demand may in fact lead to lower fluxes of water from tropical rainforests and a reduced capacity of these forests to store carbon.
The record contains meteorological and forest inventory data in addition to data on soil water potential, sapflow measurements and tree hydraulic vulnerability measures from Robson Creek and Cow Bay study sites in Far North Queensland. The measurements occurred over a period of two years form 2019 to 2020.

Credit
We at TERN acknowledge the Traditional Owners and Custodians throughout Australia, New Zealand and all nations. We honour their profound connections to land, water, biodiversity and culture and pay our respects to their Elders past, present and emerging.

This work was supported by ARC grant DP17010409 to PM; Catalan science and technology grant, Beatriu de Pinós, BP2021 00224 to Oliver Binks (OB). OB gratefully acknowledges the Daintree Discovery Centre for use of their facilities and power supply for the field equipment. Mike Liddell acknowledges the support of TERN in maintaining the field infrastructure at Cow Bay and Robson Creek, TERN is the Australian Government's Terrestrial Ecosystem Research Network (www.tern.org.au).

Purpose
The study was conducted to understand the climatic drivers of transpiration of tropical rainforests, and the feedbacks between water stress in trees and forest structure and function.