Forest reorganization sustains carbon sequestration under climate change
Data files
Mar 02, 2026 version files 435.87 MB
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3rd_bgd_baseline.xml
31.02 KB
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carbon_bgd_baseline_wet_warm_1.sqlite
272.16 MB
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README.md
10.11 KB
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sqlite_as_csv.zip
157.47 MB
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stoko_env_grid_new.asc
711.10 KB
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stoko_env_new.txt
5.49 MB
Abstract
Forests currently mitigate anthropogenic climate change by sequestering substantial amounts of carbon, but future carbon dynamics are expected to vary across the temperate forest biome. Previously cold-limited ecosystems with low disturbance activity could increase their carbon uptake while water-limited ecosystems with high disturbance activity could become a carbon source to the atmosphere. However, forests dynamically adapt to changing climate and disturbance regimes by reorganizing their composition and structure, with unclear consequences for future carbon dynamics. We asked how the carbon dynamics of reorganizing forests differ from those of resilient forests, i.e., forests that conserve their composition and structure under climate change, and how shifts in composition and structure drive future forest carbon. We simulated long-term forest and carbon dynamics under current and future climate for three contrasting temperate forest national parks, spanning a gradient from low disturbance activity in Shiretoko, JP, to intermediate disturbance activity in Berchtesgaden, DE, and high disturbance activity in Grand Teton, US. Under climate change, carbon stores increased in Shiretoko, remained close to current levels in Berchtesgaden, and decreased in Grand Teton. Forests that reorganized, i.e., exhibited compositional and/or structural change, generally took up more carbon than resilient forests. Changes in forest carbon cycling were consistently associated with changes in forest structure across systems, whereas the effects of tree species composition change were less consistent. We conclude that resilience in composition and structure does not guarantee continuity in ecosystem functioning, suggesting that reorganization could be necessary to maintain forest carbon stocks in a changing climate.
Description of the data
We used the individual-based forest landscape and disturbance model iLand to simulate long-term forest and carbon dynamics under current and future climate for three contrasting temperate forest national parks (Shiretoko, JP: low disturbance activity; Berchtesgaden, DE: intermediate disturbance activity; Grand Teton, US: high disturbance activity).
Input files
All input files needed to replicate the simulations for the three landscapes in iLand (https://iland-model.org/) are available in this Zendodo repository*: https://doi.org/10.5281/zenodo.13842317
Folder name (n=3): "iLand_project" [landscape]; separated with "_"
- project files (.xml): one for running scenarios without climate change ("baseline"), one for running scenarios with climate change ("change")
An example project file for running simulations Berchtesgaden without climate change ("baseline") is included in this repository ("3rd_bgd_baseline.xml").
- database: databases for climate and tree species
- gis: spatial input data
- init: files for initializing tree vegetation
- lip: light interference pattern files
- log: empty, for storing log files written during simulations
- output: empty, for storing output files written during simulations
- scripts: scripts detailing atmospheric CO2 values and wind events, code for wiritng user-specific output ("customagg")
- bite (only Grand Teton): script file for running the Mountain Pine Beetle in the BITE module
Extensive model documentation on iLand can be found at https://iland-model.org and the full model source code at https://github.com/edfm-tum/iland-model. Additionally, the iLand book features in-depth tutorials for running simulations in iLand using the uploaded data (e.g., Chapter 3, https://iland-model.org/iland-book/).
*Updated environment grid and file for the Shiretoko landscape:
- stoko_env_grid_new.asc: replacement for resourceUnit_snp_220908.asc
- stoko_env_new.txt: replacment for environment_final.txt
Data files
For each simulation (n=300) multiple output files (.sqlite, .csv, .asc) containing data on forest composition and structure as well as simulated disturbances were generated.
Since the output files range from ~200-1500 MB in size per simulation, only the files for one simulation are uploaded as an example (Berchtesgaden landscape, baseline climate, replicate 1). The other files can be requested from the corresponding author, Christina Dollinger.
Main output files (.sqlite, n=300)
File name: carbon [landscape] [scenario] [precipitationChange] [temperatureChange] [replicate].sqlite; separated with "_"
- Landscapes (n=3): bgd (Berchtesgaden), grte (Grand Teton), stoko (Shiretoko)
- Scenarios (n=2): baseline (no climate change simulated), change (climate change simulated)
- Precipitation change (n=2): wet, dry
- Temperature change (n=2): warm, hot
- Replicate (n=20): 1-20
Each .sqlite database contains multiple output tables (n=12-13, dp. on landscape):
| Table name | Description |
|---|---|
| barkbeetle (only in Berchtesgaden) | Barkbeetle related outputs per year. The outputs are created after each year (or spread event) and contain information about bark beetle generations, spread and damage for the total landscape. Written every year. https://iland-model.org/barkbeetle+module#BarkBeetle_module_output |
| carbon | Output of carbon pools above- and below-ground. Values are always aggregated per hectare. Written in years 0, 80, and 180. https://iland-model.org/Outputs?highlight=basal+area#Carbon_and_nitrogen_pools_above_and_belowground_per_RU_yr |
| carbonflow | Output of carbon fluxes. Values are always aggregated per hectare. Written in years 160, 170, and 180. https://iland-model.org/Outputs?highlight=basal+area#Carbon_fluxes_per_RU_or_landscape_yr |
| custom_tree1 | Data on trees (height >4 m) on patches in the first year post disturbance. Type: "customagg"-output (highly customizable). https://iland-model.org/dynamic+outputs#customagg_output |
| custom_sapBig | Data on saplings (height between 1.3-4 m) on patches in the first year post disturbance. Type: "customagg"-output (highly customizable). https://iland-model.org/dynamic+outputs#customagg_output |
| custom_sapSmall | Data on saplings (height <1.3 m) on patches in the first year post disturbance. Type: "customagg"-output (highly customizable). https://iland-model.org/dynamic+outputs#customagg_output |
| customagg | Empty |
| dynamicstand | User-defined outputs for tree aggregates for each stand and species. Written every 10 years. https://iland-model.org/Outputs?highlight=basal+area#dynamic_stand_output_by_species_RU |
| fire (only in Grand Teton) | Fire event aggregates per fire event. The output contains a row for each (ignited) fire event. Written every year. https://iland-model.org/fire+module#Fire_specific_outputs |
| landscape | Output of aggregates on the level of landscape x species. Values are always aggregated per hectare. Written every year. https://iland-model.org/Outputs#Landscape_aggregates_per_species |
| runinfo | Timestamp of the simulation start and iLand version information. |
| sapling | Output of the establishment/sapling layer per resource unit and species. The output covers trees between a dbh of 1cm (height>1.3m) and the recruitment threshold (i.e. a height of 4m). Written every 10 years. https://iland-model.org/Outputs#Sapling_Output |
| water | empty |
| wind (only in Berchtesgaden and Shiretoko) | Wind related output generated by event per year. Written every year. https://iland-model.org/wind+module#Wind_disturbance_module_output |
For easier accessability, the example sqlite database ("carbon_bgd_baseline_wet_warm_1.sqlite") has been unpacked and saved as individual csv-files (in the folder "sqlite_as_csv.zip").
Code repository
Code files used for data preparation and analysis can be found here: https://github.com/CEDollinger/3rd_analysis