---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '22540'
abstract:
- lang: eng
text: The reliable partitioning of the terrestrial latent heat flux into evaporation
(E) and transpiration (T) is important for linking carbon and water cycles and
for better understanding ecosystem functioning at local, regional and global scales.
Previous research revealed that the transpiration-to-evapotranspiration ratio
(T/ET) is well constrained across ecosystems and is nearly independent of vegetation
characteristics and climate. Here we investigated the reasons for such a global
constancy in present-day T/ET by jointly analysing observations and process-based
model simulations. Using this framework, we also quantified how the ratio T/ET
could be influenced by changing climate. For present conditions, we found that
the various components of land surface evaporation (bare soil evaporation, below
canopy soil evaporation, evaporation from interception), and their respective
ratios to plant transpiration, depend largely on local climate and equilibrium
vegetation properties. The systematic covariation between local vegetation characteristics
and climate, resulted in a globally constrained value of T/ET = ∼70 ± 9% for undisturbed
ecosystems, nearly independent of specific climate and vegetation attributes.
Moreover, changes in precipitation amounts and patterns, increasing air temperatures,
atmospheric CO2 concentration, and specific leaf area (the ratio of leaf area
per leaf mass) was found to affect T/ET in various manners. However, even extreme
changes in the aforementioned factors did not significantly modify T/ET.
article_number: '104012'
article_processing_charge: No
article_type: letter_note
author:
- first_name: Athanasios
full_name: Paschalis, Athanasios
last_name: Paschalis
- first_name: Simone
full_name: Fatichi, Simone
id: cf8e546b-a9b0-11f0-a43b-aa89ed1b56d6
last_name: Fatichi
- first_name: Christoforos
full_name: Pappas, Christoforos
last_name: Pappas
- first_name: Dani
full_name: Or, Dani
last_name: Or
citation:
ama: Paschalis A, Fatichi S, Pappas C, Or D. Covariation of vegetation and climate
constrains present and future T/ET variability. Environmental Research Letters.
2018;13(10). doi:10.1088/1748-9326/aae267
apa: Paschalis, A., Fatichi, S., Pappas, C., & Or, D. (2018). Covariation of
vegetation and climate constrains present and future T/ET variability. Environmental
Research Letters. IOP Publishing . https://doi.org/10.1088/1748-9326/aae267
chicago: Paschalis, Athanasios, Simone Fatichi, Christoforos Pappas, and Dani Or.
“Covariation of Vegetation and Climate Constrains Present and Future T/ET Variability.”
Environmental Research Letters. IOP Publishing , 2018. https://doi.org/10.1088/1748-9326/aae267.
ieee: A. Paschalis, S. Fatichi, C. Pappas, and D. Or, “Covariation of vegetation
and climate constrains present and future T/ET variability,” Environmental
Research Letters, vol. 13, no. 10. IOP Publishing , 2018.
ista: Paschalis A, Fatichi S, Pappas C, Or D. 2018. Covariation of vegetation and
climate constrains present and future T/ET variability. Environmental Research
Letters. 13(10), 104012.
mla: Paschalis, Athanasios, et al. “Covariation of Vegetation and Climate Constrains
Present and Future T/ET Variability.” Environmental Research Letters, vol.
13, no. 10, 104012, IOP Publishing , 2018, doi:10.1088/1748-9326/aae267.
short: A. Paschalis, S. Fatichi, C. Pappas, D. Or, Environmental Research Letters
13 (2018).
das_tickbox: '1'
date_created: 2026-07-27T12:30:24Z
date_published: 2018-10-05T00:00:00Z
date_updated: 2026-08-06T07:46:04Z
day: '05'
ddc:
- '550'
doi: 10.1088/1748-9326/aae267
extern: '1'
has_accepted_license: '1'
intvolume: ' 13'
issue: '10'
keyword:
- T/ET
- Evapotranspiration partitioning
- Ecohydrology
- Modelling
- Climate change
language:
- iso: eng
license: https://creativecommons.org/licenses/by/3.0/
main_file_link:
- open_access: '1'
url: https://doi.org/10.1088/1748-9326/aae267
month: '10'
oa: 1
oa_version: Published Version
publication: Environmental Research Letters
publication_identifier:
eissn:
- 1748-9326
publication_status: published
publisher: 'IOP Publishing '
quality_controlled: '1'
scopus_import: '1'
status: public
title: Covariation of vegetation and climate constrains present and future T/ET variability
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/3.0/legalcode
name: Creative Commons Attribution 3.0 Unported (CC BY 3.0)
short: CC BY (3.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 13
year: '2018'
...
---
OA_place: publisher
OA_type: free access
_id: '22536'
abstract:
- lang: eng
text: Increasing concentrations of atmospheric carbon dioxide are expected to affect
carbon assimilation and evapotranspiration (ET), ultimately driving changes in
plant growth, hydrology, and the global carbon balance. Direct leaf biochemical
effects have been widely investigated, whereas indirect effects, although documented,
elude explicit quantification in experiments. Here, we used a mechanistic model
to investigate the relative contributions of direct (through carbon assimilation)
and indirect (via soil moisture savings due to stomatal closure, and changes in
leaf area index) effects of elevated CO2 across a variety of ecosystems. We specifically
determined which ecosystems and climatic conditions maximize the indirect effects
of elevated CO2. The simulations suggest that the indirect effects of elevated
CO2 on net primary productivity are large and variable, ranging from less than
10% to more than 100% of the size of direct effects. For ET, indirect effects
were, on average, 65% of the size of direct effects. Indirect effects tended to
be considerably larger in water-limited ecosystems. As a consequence, the total
CO2 effect had a significant, inverse relationship with the wetness index and
was directly related to vapor pressure deficit. These results have major implications
for our understanding of the CO2 response of ecosystems and for global projections
of CO2 fertilization, because, although direct effects are typically understood
and easily reproducible in models, simulations of indirect effects are far more
challenging and difficult to constrain. Our findings also provide an explanation
for the discrepancies between experiments in the total CO2 effect on net primary
productivity.
article_processing_charge: No
article_type: original
author:
- first_name: Simone
full_name: Fatichi, Simone
id: cf8e546b-a9b0-11f0-a43b-aa89ed1b56d6
last_name: Fatichi
- first_name: Sebastian
full_name: Leuzinger, Sebastian
last_name: Leuzinger
- first_name: Athanasios
full_name: Paschalis, Athanasios
last_name: Paschalis
- first_name: J. Adam
full_name: Langley, J. Adam
last_name: Langley
- first_name: Alicia
full_name: Donnellan Barraclough, Alicia
last_name: Donnellan Barraclough
- first_name: Mark J.
full_name: Hovenden, Mark J.
last_name: Hovenden
citation:
ama: Fatichi S, Leuzinger S, Paschalis A, Langley JA, Donnellan Barraclough A, Hovenden
MJ. Partitioning direct and indirect effects reveals the response of water-limited
ecosystems to elevated CO. Proceedings of the National Academy of Sciences.
2016;113(45):12757-12762. doi:10.1073/pnas.1605036113
apa: Fatichi, S., Leuzinger, S., Paschalis, A., Langley, J. A., Donnellan Barraclough,
A., & Hovenden, M. J. (2016). Partitioning direct and indirect effects reveals
the response of water-limited ecosystems to elevated CO. Proceedings of the
National Academy of Sciences. National Academy of Sciences. https://doi.org/10.1073/pnas.1605036113
chicago: Fatichi, Simone, Sebastian Leuzinger, Athanasios Paschalis, J. Adam Langley,
Alicia Donnellan Barraclough, and Mark J. Hovenden. “Partitioning Direct and Indirect
Effects Reveals the Response of Water-Limited Ecosystems to Elevated CO.” Proceedings
of the National Academy of Sciences. National Academy of Sciences, 2016. https://doi.org/10.1073/pnas.1605036113.
ieee: S. Fatichi, S. Leuzinger, A. Paschalis, J. A. Langley, A. Donnellan Barraclough,
and M. J. Hovenden, “Partitioning direct and indirect effects reveals the response
of water-limited ecosystems to elevated CO,” Proceedings of the National Academy
of Sciences, vol. 113, no. 45. National Academy of Sciences, pp. 12757–12762,
2016.
ista: Fatichi S, Leuzinger S, Paschalis A, Langley JA, Donnellan Barraclough A,
Hovenden MJ. 2016. Partitioning direct and indirect effects reveals the response
of water-limited ecosystems to elevated CO. Proceedings of the National Academy
of Sciences. 113(45), 12757–12762.
mla: Fatichi, Simone, et al. “Partitioning Direct and Indirect Effects Reveals the
Response of Water-Limited Ecosystems to Elevated CO.” Proceedings of the National
Academy of Sciences, vol. 113, no. 45, National Academy of Sciences, 2016,
pp. 12757–62, doi:10.1073/pnas.1605036113.
short: S. Fatichi, S. Leuzinger, A. Paschalis, J.A. Langley, A. Donnellan Barraclough,
M.J. Hovenden, Proceedings of the National Academy of Sciences 113 (2016) 12757–12762.
das_tickbox: '1'
date_created: 2026-07-27T12:30:24Z
date_published: 2016-11-08T00:00:00Z
date_updated: 2026-08-06T08:08:46Z
day: '08'
doi: 10.1073/pnas.1605036113
extern: '1'
external_id:
pmid:
- '27791074'
intvolume: ' 113'
issue: '45'
keyword:
- carbon dioxide
- modeling
- FACE
- soil moisture
- evapotranspiration
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1073/pnas.1605036113
month: '11'
oa: 1
oa_version: Published Version
page: 12757-12762
pmid: 1
publication: Proceedings of the National Academy of Sciences
publication_identifier:
eissn:
- 1091-6490
issn:
- 0027-8424
publication_status: published
publisher: National Academy of Sciences
quality_controlled: '1'
scopus_import: '1'
status: public
title: Partitioning direct and indirect effects reveals the response of water-limited
ecosystems to elevated CO
type: journal_article
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
volume: 113
year: '2016'
...