DOI: 10.5061/dryad.np5hqc085
title: Climatic niche position determines post-fire resilience in Mediterranean forests

description: Fires are a common and significant disturbance in Mediterranean forest
 ecosystems, with a prominent role in their dynamics. The increased
 frequency, intensity, and extent of fires due to climate change are,
 however, expected to exceed forests resilience capacity. It is still
 unknown how resilience capacity changes across species’ biogeographical
 ranges in relation to pre- and post-fire environmental variability. We
 analyzed the resilience of Mediterranean pinewoods (Pinus halepensis and
 P. nigra) to fire in the Eastern Iberian Peninsula and considered the
 influence of pre- and post-fire climate conditions typified through the
 species’ climate niche. To assess forest resilience, we applied the
 Ecological Dynamic Regime (EDR) framework, a methodological approach to
 quantify the deviation of disturbed trajectories from their dynamic
 regimes using three indices: amplitude, recovery, and net change. Then, we
 evaluated how fire characteristics (severity), site attributes (exposure,
 rockiness), and deviations in the distance to the niche core and edge of
 the burned populations (centrality-marginality gradient) modulate their
 resilience to fire. Over 50% of the burned plots exhibited large net
 change from their dynamic regimes in the mid-term, denoting poor
 resilience regardless of the species regenerative strategy, and
 transitioned to shrublands or a different forest type after the fire.
 Recovery and net change exhibited differences between the two studied
 species: forests dominated by P. halepensis were overall more resilient to
 fire across the study range, especially in moist sites, while burned P.
 nigra forests showed poor recovery and large net changes after fire. For
 both species, forests location within the climatic niche before and after
 fire significantly explained post-fire resilience. In general, forests
 near their climatic niche core showed higher resilience compared to those
 close to the dry edge of the niche. Synthesis: Our study reveals that
 post-fire forest resilience depends not only on fire severity and fire
 characteristics but also on the climatic niche position of the forests. As
 climate warms and the frequency and intensity of fires increase, forest
 species will be pushed towards the dry edge of their climatic niches,
 likely increasing their vulnerability.
description: # Climatic niche position determines post-fire resilience in Mediterranean
 forests Dataset DOI:
 [10.5061/dryad.np5hqc085](https://doi.org/10.5061/dryad.np5hqc085) ##
 Description of the data and file structure This dataset contains the data
 and code required to replicate analyses in *Climatic niche position
 determines post-fire resilience in Mediterranean forests* (Codina et al.
 2026). We analyzed the resilience of Mediterranean pinewoods (*Pinus
 halepensis* and *P. nigra*) to fire in the Eastern Iberian Peninsula and
 considered the influence of pre- and post-fire climate conditions typified
 through the species’ climate niche. To assess forest resilience, we
 applied the Ecological Dynamic Regime (EDR) framework, a methodological
 approach to quantify the deviation of disturbed trajectories from their
 dynamic regimes using three indices: amplitude, recovery, and net change.
 Then, we evaluated how fire characteristics (severity), site attributes
 (exposure, rockiness), and deviations in the distance to the niche core
 and edge of the burned populations (centrality-marginality gradient)
 modulate their resilience to fire. ### Files and variables #### File:
 climatic_niche_edges.R **Description:** R script used to characterize
 species climatic niche edges in the PCA space and calculate distances of
 plot-level observations. #### File: metadata.xlsx
 **Description:** Metadata file providing variable definitions, units, and
 notes for all datasets included in the repository. #### File:
 resilience_indices.R **Description:** R script used to compute forest
 resilience indices (Amplitude, Recovery, Net Change) based on deviations
 from representative successional trajectories within the Ecological
 Dynamic Regimes (EDR) framework. #### File:
 centroid_distances_CATALUNYA_10years.csv **Description:** Plot-level
 climatic niche positions and distances to species climatic niche centroids
 and modes for Catalonia, calculated using climate data averaged over the
 10-year pre-fire period. ##### Variables * X: Row index. * CODI: Plot
 identifier. * species: Scientific name of the species. * value: BA of the
 species in the plot. * Axis1: Position along PCA axes of the climatic
 niche space. * Axis2: Position along PCA axes of the climatic niche space.
 * Axis3: Position along PCA axes of the climatic niche space. * Axis4:
 Position along PCA axes of the climatic niche space. * Axis5: Position
 along PCA axes of the climatic niche space. * centroid_pca1: Species
 climatic niche centroid coordinate along PCA axis 1. * centroid_pca2:
 Species climatic niche centroid coordinate along PCA axis 2. * mode_pca1:
 Species climatic niche mode coordinate along PCA axis 1. * mode_pca2:
 Species climatic niche mode coordinate along PCA axis 2. *
 centroid_dist2d: Euclidean distance from the plot to the species climatic
 niche centroid in PCA1–PCA2 space. * mode_dist2d: Euclidean distance from
 the plot to the species climatic niche mode in PCA1–PCA2 space. #### File:
 centroid_distances_CATALUNYA_postfire.csv **Description:** Plot-level
 climatic niche positions and distances to species climatic niche centroids
 and modes for Catalonia, calculated using climate data averaged over the 3
 years post-fire period. **Variables**: same as
 `centroid_distances_CATALUNYA_10years.csv`. #### File:
 centroid_distances_MURCIA_10years.csv **Description:** Plot-level climatic
 niche positions and distances to species climatic niche centroids and
 modes for Murcia, calculated using climate data averaged over the 10-year
 pre-fire period. **Variables**: same as
 `centroid_distances_CATALUNYA_10years.csv`. #### File:
 centroid_distances_CATALUNYA_prefire.csv **Description:** Plot-level
 climatic niche positions and distances to species climatic niche centroids
 and modes for Catalonia, calculated using climate data averaged over the
 3-year pre-fire period. **Variables**: same as
 `centroid_distances_CATALUNYA_10years.csv`. #### File:
 centroid_distances_MURCIA_postfire.csv **Description:** Plot-level
 climatic niche positions and distances to species climatic niche centroids
 and modes for Murcia, calculated using climate data averaged over the
 3-year post-fire period. **Variables**: same as
 `centroid_distances_CATALUNYA_10years.csv`. #### File:
 centroid_distances_MURCIA_prefire.csv **Description:** Plot-level climatic
 niche positions and distances to species climatic niche centroids and
 modes for Murcia, calculated using climate data averaged over the 3-year
 pre-fire period. **Variables**: same as
 `centroid_distances_CATALUNYA_10years.csv`. #### File: perc_5_df.csv
 **Description:** Coordinates defining the outer boundary (5th percentile)
 of species climatic niches in PCA space, used to characterize climatic
 niche edges. ##### Variables * species: Scientific name of the species. *
 pca1: PCA axis 1 coordinate of the niche edge. * pca2: PCA axis 2
 coordinate of the niche edge. #### File: pinhalCAT_variables.csv
 **Description:** Plot-level resilience indices and environmental variables
 for *Pinus halepensis* forests in Catalonia. ##### Variables * PLOT: Plot
 identifier. * Index1: Amplitude. * Index2: Recovery. * Index3: Net change.
 * distance: Distance to the nearest unburned tree patch (m). * rdnbr:
 Relativized differenced Normalized Burn Ratio (fire severity). *
 cwdm_prefire: Tree community–weighted distance to the climatic edge
 (pre-fire). * cwdc_prefire: Tree community–weighted distance to the
 climatic core (pre-fire). * cwdm_postfire: Tree community–weighted
 distance to the climatic edge (post-fire). * cwdc_postfire: Tree
 community–weighted distance to the climatic core (post-fire). *
 cwdm_10years: Tree community–weighted distance to the climatic edge
 (10-year pre-fire). * cwdc_10years: Tree community–weighted distance to
 the climatic core (10-year pre-fire). * srad: Mean annual solar radiation.
 * rocosid: Rockiness index. #### File: pinhalMUR_variables.csv
 **Description:** Plot-level resilience indices and environmental variables
 for *Pinus halepensis* forests in Murcia. **Variables:** same as
 `pinhalCAT_variables.csv`. #### File: pinnigCAT_variables.csv
 **Description:** Plot-level resilience indices and environmental
 covariates for *Pinus nigra* forests in Catalonia. **Variables:** same as
 `pinhalCAT_variables.csv`. #### File: RT_distance_pinhalCAT.csv
 **Description:** Distances from plot states to the representative
 successional trajectory for *Pinus halepensis* forests in Catalonia. #####
 Variables * PLOT: Plot identifier. * X1: Distance from the pre-disturbance
 state to the representative trajectory * X2: Distance from the immediate
 post-disturbance state to the representative trajectory. * X3: Distance
 from the later post-disturbance state to the representative trajectory.
 #### File: RT_distance_pinhalMUR.csv **Description:** Distances from plot
 states to the representative successional trajectory for *Pinus
 halepensis* forests in Murcia. **Variables:** same as
 `RT_distance_pinhalCAT.csv`. #### File: RT_distance_pinnigCAT.csv
 **Description:** Distances from plot states to the representative
 successional trajectory for *Pinus nigra* forests in Catalonia.
 **Variables:** same as `RT_distance_pinhalCAT.csv`. #### File:
 index_pinhalCAT.csv **Description:** Resilience indices derived from
 trajectory distances for *Pinus halepensis* forests in Catalonia. #####
 Variables * PLOT: Plot identifier. * X1: Distance from the pre-disturbance
 state to the representative trajectory * X2: Distance from the immediate
 post-disturbance state to the representative trajectory. * X3: Distance
 from the later post-disturbance state to the representative trajectory. *
 Index1: Amplitude. * Index2: Recovery. * Index3: Net Change. #### File:
 index_pinhalMUR.csv **Description:** Resilience indices derived from
 trajectory distances for *Pinus halepensis* forests in Murcia.
 **Variables:** same as `index_pinhalCAT.csv`. #### File:
 index_pinnigCAT.csv **Description:** Resilience indices derived from
 trajectory distances for *Pinus nigra* forests in Catalonia.
 **Variables:** same as `index_pinhalCAT.csv`. #### File:
 edges_10y_pinhal.csv **Description:** Plot-level climatic niche positions
 and classification relative to climatic niche edges for *Pinus halepensis*
 using 10-year pre-fire climate. ##### Variables * CODI: Plot identifier. *
 species: Scientific name. * value: Observed relative abundance (or cover).
 * Axis1: PCA climatic niche coordinates. * Axis2: PCA climatic niche
 coordinates. * Axis3: PCA climatic niche coordinates. * Axis4: PCA
 climatic niche coordinates. * Axis5: PCA climatic niche coordinates. *
 centroid_pca1: Species niche centroid coordinates. * centroid_pca2:
 Species niche centroid coordinates. * mode_pca1: Species niche mode
 coordinates. * mode_pca2: Species niche mode coordinates. *
 centroid_dist2d: Distances to centroid. * mode_dist2d: Distances to mode.
 * quadrant: Climatic niche closer edge position category. #### File:
 edges_10y_pinnig.csv **Description:** Same as above for *Pinus nigra*.
 **Variables:** same as `edges_10y_pinhal.csv`. #### File:
 edges_post_pinhal.csv **Description:** Same as `edges_10y_pinhal.csv`,
 using post-fire climatic conditions. **Variables:** same as
 `edges_10y_pinhal.csv`. #### File: edges_pre_pinnig.csv
 **Description:** Same as `edges_10y_pinhal.csv`, using pre-fire climatic
 conditions for *Pinus nigra*. **Variables:** same as
 `edges_10y_pinhal.csv`. #### File: edges_pre_pinhal.csv
 **Description:** Same as `edges_10y_pinhal.csv`, using pre-fire climatic
 conditions for *Pinus halepensis*. **Variables:** same as
 `edges_10y_pinhal.csv`. #### File: edges_post_pinnig.csv
 **Description:** Same as `edges_10y_pinhal.csv`, using post-fire climatic
 conditions for *Pinus nigra*. **Variables:** same as
 `edges_10y_pinhal.csv`. ## Code/software All data files included in this
 repository can be viewed and manipulated using **free and open-source
 software**. ### Software required The analyses and data processing were
 performed using **R** (version ≥ **4.2.0**), an open-source statistical
 computing environment (R Core Team).\ R is freely available at:
 [https://www.r-project.org/](https://www.r-project.org/) The CSV and XLSX
 files can be opened with any spreadsheet software (e.g. LibreOffice Calc,
 Microsoft Excel), although R is recommended to ensure correct handling of
 numeric formats and reproducibility. ### R packages used The following R
 packages were used to run the scripts included in this repository: *
 **Base and data manipulation** * `dplyr` * `readr` * `stringi` * `janitor`
 * **Multivariate analysis and ordination** * `ade4` * `vegan` *
 `factoextra` * **Climatic niche characterization** * `ks` * `ecospat` *
 **Spatial and raster data handling** * `raster` * `sp` * `rgdal` * `rgeos`
 * `maptools` * `rasterVis` * **Nearest-neighbour distance calculations** *
 `RANN` * **Plotting and visualization** * `ggplot2` * `RColorBrewer` *
 `plot3D` * `rgl` * `maps` * `ggmap` All packages are available from CRAN
 and can be installed using `install.packages()`. ### Scripts included *
 **`climatic_niche_edges.R`**\ R script used to characterize species
 climatic niche edges in the PCA space and calculate distances of
 plot-level observations. * **`resilience_indices.R`**\  R script used to
 compute forest resilience indices (Amplitude, Recovery, Net Change) based
 on deviations from representative successional trajectories within the
 Ecological Dynamic Regimes (EDR) framework. ## Access information Our data
 was derived from: * National Forest Inventory data (IFN2, IFN3 &
 IFN4):
 [https://www.miteco.gob.es/ca/biodiversidad/temas/inventarios-nacionales/inventario-forestal-nacional.html](https://www.miteco.gob.es/ca/biodiversidad/temas/inventarios-nacionales/inventario-forestal-nacional.html) * Climate data (CHELSA): [https://www.chelsa-climate.org/datasets](https://www.chelsa-climate.org/datasets)