Details

Autor(en) / Beteiligte

• De Kauwe, Martin G.
• Medlyn, Belinda E.
• Tissue, David T.

Titel

To what extent can rising [CO2] ameliorate plant drought stress?

Ist Teil von

• The New phytologist, 2021-09, Vol.231 (6), p.2118-2124

Ort / Verlag

Lancaster: Wiley Subscription Services, Inc

Erscheinungsjahr

2021

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• Summary Plant responses to elevated atmospheric carbon dioxide (eCO2) have been hypothesized as a key mechanism that may ameliorate the impact of future drought. Yet, despite decades of experiments, the question of whether eCO2 reduces plant water use, yielding ‘water savings’ that can be used to maintain plant function during periods of water stress, remains unresolved. In this Viewpoint, we identify the experimental challenges and limitations to our understanding of plant responses to drought under eCO2. In particular, we argue that future studies need to move beyond exploring whether eCO2 played ‘a role’ or ‘no role’ in responses to drought, but instead more carefully consider the timescales and conditions that would induce an influence. We also argue that considering emergent differences in soil water content may be an insufficient means of assessing the impact of eCO2. We identify eCO2 impact during severe drought (e.g. to the point of mortality), interactions with future changes in vapour pressure deficit and uncertainty about changes in leaf area as key gaps in our current understanding. New insights into CO2 × drought interactions are essential to better constrain model theory that governs future climate model projections of land–atmosphere interactions during periods of water stress.