Data from: Climate change and exotic pathogens shift carbon allocation in Mediterranean mixed forests
Abstract
Forecasting the effects of global change drivers on ecosystems is one of the most pressing challenges for scientists worldwide. Particularly, climate change and exotic pathogens might have a large impact on plant community dynamics and ecosystem functioning through changes in carbon uptake and sinks. Nevertheless, we still have a poor understanding of the combined effects of these two drivers on plant communities. Here, we explored the impact of rainfall reduction and exotic pathogens on the carbon balance of Mediterranean tree species. For this, we performed a three-year field experiment taking advantage of rainfall exclusion infrastructures (30% exclusion) installed in the southernmost European oak forests invaded by the aggressive exotic pathogen Phytophthora cinnamomi. We measured a set of 10 variables representative of tree carbon sources (photosynthetic rates) and sinks (primary production, reproduction, defence and reserves) in adult trees of three species in two forest types: closed forests of Quercus suber and Q. canariensis, and open woodlands of Q. suber and Olea europaea. We found a large variability in the sensitivity of the different carbon source and sinks to the effects of drought and pathogens, from variables highly sensitive to both factors (carbon fixation and reproduction, root chemistry) to variables only responsive to drought (litter production) or totally unresponsive (tree trunk, leaf chemistry). Although negative effects predominated, positive effects of rainfall exclusion were also detected in wet years, likely due to a reduction of pathogen abundance in a drier soil. Trade-offs between carbon sinks appeared in all tree species, but rainfall exclusion only modified trade-offs in Q. suber, the species most susceptible to P. cinnamomi.
Synthesis: We provide evidence on the complexity of the combined effects of abiotic (drought) and biotic (pathogens) global change drivers on carbon source and sinks of adult trees, including both negative direct effects and positive indirect effects. Our results showed that these effects varied among co-existing species, particularly for carbon sinks directly related to tree demography (reproduction). Therefore, long-term changes in the structure of Mediterranean mixed forests might be expected towards the dominance of species highly resistant to both drought and pathogens.
README: Data from: Climate change and exotic pathogens shift carbon allocation in Mediterranean mixed forests
GENERAL INFORMATION
- Author Information: Álvaro Gaytán, Luis Matías, Óscar Godoy, Ignacio M. Pérez-Ramos, Pablo Homet, Xoaquín Moreira and Lorena Gómez-Aparicio
- Date of data collection: 2016-2018
- Geographic location of data collection: PN Los Alcornocales, Cadiz (Spain)
DATA & FILE OVERVIEW
In the Data file, two datasets are available:
One for the Closed forest and other for the Open woodand, which contain the same variables
Variable List:
- Block: Block of tres in the experiment containing a rainfall exclusion and a control plot
- Treatment: Rainfall exclusion or Control
- Tree: Individual tree numbers
- Species: Tree species (Quercus suber, Quercus canariensis or Olea europea)
- DBH: Trunk diameter at breast height (cm)
- Sand: Percentage of sand in the soil (%)
- Pci16: Levels of P. cinnamomi in 2016 (number of colonies)
- Pci17: Levels of P. cinnamomi in 2017 (number of colonies)
- Pci18: Levels of P. cinnamomi in 2018 (number of colonies)
- Photo17: Photosynthesis in 2017 (umol CO2 m-2 s-1; only measured in a subset of the trees)
- Photo18: Photosynthesis in 2018 (umol CO2 m-2 s-1; only measured in a subset of the trees)
- Dendro16: Dentrometer measurement in 2016 (cm)
- Dendro17: Dentrometer measurement in 2017 (cm)
- Dendro18: Dentrometer measurement in 2018 (cm)
- Litter16: Leaf litter in 2016 (g)
- Litter17: Leaf litter in 2017 (g)
- Litter18: Leaf litter in 2018 (g)
- N.Total16: Number of acorns in 2016
- N.Total17: Number of acorns in 2017 (only in the closed forest. Missing data in the open woodland due to acorn storage problems)
- N.Total18: Number of acorns in 2018
- N.Abort16: Number of aborted acorns in 2016
- N.Abort17: Number of aborted acorns in 2017 (only in the closed forest. Missing data in the open woodland due to acorn storage problems)
- N.Abort18: Number of aborted acorns in 2018
- Olives16: Number of Olea fruits in 2016 (only in the open Woodland, there are not Olea trees in the open woodland)
- Olives17: Number of Olea fruits in 2017 (only in the open Woodland, there are not Olea trees in the open woodland)
- Olives18: Number of Olea fruits in 2018 (only in the open Woodland, there are not Olea trees in the open woodland)
- LeafPh_16: Concentrations of leaf phenols in 2016 (mg g-1, in few empty cells where the quantification failed)
- LeafPh_17: Concentrations of leaf phenols in 2017 (mg g-1, in few empty cells where the quantification failed)
- LeafPh_18: Concentrations of leaf phenols in 2018 (mg g-1, in few empty cells where the quantification failed)
- RootPh_16: Concentrations of root phenols in 2016 (mg g-1, in few empty cells where the quantification failed)
- RootPh_17: Concentrations of root phenols in 2017 (mg g-1, in few empty cells where the quantification failed)
- RootPh_18: Concentrations of root phenols in 2018 (mg g-1, in few empty cells where the quantification failed)
- LeafNSC_16: Concentrations of leaf non-structural carbohydrates in 2016 (mg g-1, in few empty cells where the quantification failed)
- LeafNSC_17: Concentrations of leaf non-structural carbohydrates in 2017 (mg g-1, in few empty cells where the quantification failed)
- LeafNSC_18: Concentrations of leaf non-structural carbohydrates in 2018 (mg g-1, in few empty cells where the quantification failed)
- RootNSC_16: Concentrations of root non-structural carbohydrates in 2016 (mg g-1, in few empty cells where the quantification failed)
- RootNSC_17: Concentrations of root non-structural carbohydrates in 2017 (mg g-1, in few empty cells where the quantification failed)
- RootNSC_18: Concentrations of root non-structural carbohydrates in 2018 (mg g-1, in few empty cells where the quantification failed)