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functions and services for human societies. Temperatures are increasing most rapidly in high northern latitudes, altering tree growth and competition dynamics, and modifying disturbance regimes. The effect of these cumulative changes on the ecosystem functions provided by boreal forests is difficult to predict. We used the process-based LANDIS-II forest landscape model to evaluate how climate change and timber harvesting will interact to alter the production of ecosystem functions and services in boreal forests on three study areas across a large latitudinal gradient (11°) in central Siberia. We found that the relative importance of wood harvesting as a disturbance type varied depending on latitude and its impact was always far less than that of fire. Moderate climate change increased the availability of wood for harvest in the northern landscape, but wood availability declined in the southern landscapes under any amount of climate change likely because of an increase in the frequency of fire that kept forests too young for harvest. Modest climate change (RCP6.0) increased productivity and the storage of carbon in all landscapes but severe climate change (RCP8.5) reduced both in the southernmost landscape. Harvesting as a specific driver of change in these boreal forests is likely to be relatively minor except as a forest fragmentation process. Our results provide compelling evidence that status quo forest management in these landscapes is likely not sustainable, suggesting that climate-smart forestry will be needed.
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Modeling changes in Siberian forests under climate change, 2020-2024
Boreal forests are found at high northern latitudes and form the largest terrestrial biome in the world. They comprise 30-50% of the world’s forest carbon stocks (vs. 14% in temperate forests. Temperatures are increasing rapidly in high northern latitudes (IPCC 2021), resulting in modified disturbance regimes and thawing of permafrost, and the socio-economic pressure to harvest timber is growing in currently unharvested areas. Attempts to predict how these changes will affect boreal forests must account for interactions among multiple disturbances (e.g., wind, insects, fire, harvest), seed dispersal, species growth and competition, and changing climate, and therefore uncertainty persists about how these changes will affect composition and function of this biome. Our objectives for this research were to 1) Use LANDIS-II to project forest dynamics under a range of climate and disturbance scenarios across a latitudinal gradient spanning the Siberian taiga from the arctic tundra to steppe ecotones, 2) Quantify the change in albedo and harvesting across bioclimatic zones and climates, 3) Identify the factor(s) that are the strongest drivers of these changes
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- Award ID(s):
- 2054713
- PAR ID:
- 10584918
- Editor(s):
- Lucash, Melissa S
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Edition / Version:
- 1
- Volume:
- 1
- Issue:
- 1
- Subject(s) / Keyword(s):
- terrestrial ecosystems forests models ecological dynamics fire ecology forest composition carbon cycle
- Format(s):
- Medium: X Other: text; xml; tif; csv
- Location:
- Eugene, Oregon
- Institution:
- University of Oregon
- Sponsoring Org:
- National Science Foundation
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