10.5061/DRYAD.VDNCJSXS5
Rowland, Lucy
0000-0002-0774-3216
University of Exeter
da Costa, Antonio
Federal University of Para
Oliveira, Rafael
State University of Campinas
Bittencourt, Paulo
University of Exeter
Giles, André
State University of Campinas
Coughlin, Ingrid
0000-0002-8541-2682
Australian National University
Bartholomew, David
0000-0002-8123-1817
University of Exeter
Ferreira Domingues, Tomas
University of Sao Paulo
Miatto, Raquel
University of Sao Paulo
Ferreira, Leandro
Museu Paraense Emílio Goeldi
Vasconcelos, Steel
Brazilian Agricultural Research Corporation
Junior, Joao
Federal University of Para
Oliveira, Alex
0000-0002-7380-8196
Museu Paraense Emílio Goeldi
Mencuccini, Maurizio
Centre for Research on Ecology and Forestry Applications
Meir, Patrick
Australian National University
The response of carbon assimilation and storage to long-term drought in
tropical trees is dependent on light availability
Dryad
dataset
2020
Photosynthesis
non-structural carbohydrates
leaf respiration
stomatal conductance
2020-09-23T00:00:00Z
2020-09-23T00:00:00Z
en
30906 bytes
4
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1) Whether tropical trees acclimate to long-term drought stress remains
unclear. This uncertainty is amplified if drought stress is accompanied by
changes in other drivers such as the increases in canopy light exposure
that might be induced by tree mortality or other disturbances. 2)
Photosynthetic capacity, leaf respiration, non-structural carbohydrate
(NSC) storage and stomatal conductance were measured on 162 trees at the
world’s longest running (15 yr) tropical forest drought experiment. We
test whether surviving trees have altered strategies for carbon storage
and carbon use in the drier and elevated light conditions present
following drought-related tree mortality. 3) Relative to control trees,
the surviving trees experiencing the drought treatment showed functional
responses including: i) moderately reduced photosynthetic capacity; ii)
increased total leaf NSC; and iii) a switch from starch to soluble sugars
as the main store of branch NSC. This contrasts with earlier findings at
this experiment of no change in photosynthetic capacity or NSC storage.
The changes detected here only occurred in the subset of drought-stressed
trees with canopies exposed to high radiation and were absent in trees
with less-exposed canopies, and also in the community average. In contrast
to previous results acquired through less intensive species sampling from
this experiment, we also observe no species-average drought-induced change
in leaf respiration. 4) Our results suggest that long-term responses to
drought stress are strongly influenced by a tree’s full-canopy light
environment and therefore that disturbance-induced changes in stand
density and dynamics are likely to substantially impact tropical forest
responses to climate change. We also demonstrate that, while challenging,
intensive sampling is essential in tropical forests to avoid sampling
biases caused by limited taxonomic coverage.
This file contains all of the data for the 163 trees used to create the
results for the above paper. We list these trees alongisde their taxonomic
identity, size and a series of triats. The file contains the following
fields: Plot: Whether the tree is located on the control or experimental
plot (TFE) Tree Code: Tree number on the plot Genus: Tree genus Species:
Tree species DBH..Cm.: Tree diameter at breast height (cm) Tree light
score: The canopy light index assigned to each tree Min. gs: Minimum
stomatal conductance (mol m-2 s-1) Max.gs: Maximum stomatal
conductance (mol m-2 s-1) vm25: Maximum carboxylation rate corrected to
25⁰C (micromols m-2 s-1) jm25: Maximum rate of electron
transport corrected to 25⁰C (micromols m-2 s-1) rd25: Dark respiration
rate corrected to 25⁰C (micromols m-2 s-1) Sucrose_branch: Sucrose branch
content (%) Starch_branch: Starch branch content (%) Total_NSC_branch:
Total branch non-structural carbohydrate content (%) Sucrose_leaf: Sucrose
leaf content (%) Starch_leaf: Starch leaf content (%) Total_NSC_leaf:
Total leaf non-structural carbohydrate content (%) leaf_n: Leaf Nitrogen
content (g m-2) leaf_P: Leaf Phosphorus content (g m-2) LMA: Leaf mass per
area (g m-2) Light category: Whether the tree light score translates into
a high or low light category