Carbon cycle
Shrubs and trees empty subarctic soil carbon
Open access · cc by · source: Europe PMC
At a Swedish subarctic treeline, shrub and birch plots stored far less soil organic carbon than nearby heaths and respired that carbon faster, implying woody expansion can accelerate soil C loss.
Study at a glance
- Design
- Cross-sectional — Space-for-time forest–heath transects comparing SOC and respiration under shrub expansion
- N
- N=19 · 12 Abisko + 7 Vassijaure forest–heath transects
- Population
- Subarctic treeline heath, shrub, and birch forest plots in northern Sweden
- Outcome
- Soil organic carbon stocks and respiration rates across vegetation types
Structured fields used in claim comparison tables when every cited study has a complete layer.
Key findings
At Abisko, organic-horizon SOC was 7.03 kg m⁻² on heath vs 2.98 (shrub) and 2.04 (forest). Total SOC fell from 9.01 to 4.51 kg m⁻² heath to forest. Shrub plots had the highest respiration; per kilogram of organic SOC, shrub and forest plots respired about three times heath rates. Hyphal in-growth rose from heath to forest edge.
Methodology
Authors sampled 12 Abisko and 7 Vassijaure forest–heath transects, measured organic and mineral SOC, chamber respiration, and ectomycorrhizal hyphal in-growth bags along heath–shrub–forest plots, using space-for-time as a shrub-expansion analogue.
Limitations
Space-for-time cannot prove future shrub advance will lose the same carbon; moth defoliation likely understated forest ECM growth; root C was not fully inventoried; permafrost and waterlogged tundra may respond differently.
How this study connects
Role on claims
Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.
This library holds 10 empirical papers on carbon cycle with measured outcomes rather than reviews.
Evidence for the claim as stated.
At a Swedish subarctic treeline, shrub and birch plots stored far less soil organic carbon than nearby heaths and respired that carbon faster, implying woody expansion can accelerate soil C loss.
Evidence for the claim as stated.
Space-for-time mixed structure along 12 Abisko and 7 Vassijaure forest–heath transects treated shrub expansion as an analogue. At Abisko, organic-horizon SOC was 7.03 kg m⁻² on heath versus 2.98 (shrub) and 2.04 (forest). Total SOC fell from 9.01 to 4.51 kg m⁻² heath to forest. Shrub plots had the highest respiration; per kilogram of organic SOC, shrub and forest plots respired about three times heath rates. Hyphal in-growth rose from heath to forest edge.
Evidence for the claim as stated.
Mixed-effects and adjacent hierarchical papers here are not one invasive-species result. Children's BMI growth is a traffic-pollution question (non-freeway NOₓ associated; freeway NOₓ not). Abisko space-for-time finds SOC falling from 9.01 to 4.51 kg m⁻² heath to forest as a shrub-expansion analogue. Šumava tree rings track beech versus spruce under shifting air chemistry in 35 trees. The brown-trout PVA is a suppression forecast (QE in 5.7–6.3 years; 29% if age-0 methods are skipped), not a mixed model of field counts proving those rates. The method label mixes four questions.
Evidence for the claim as stated.
Even within vegetation change, Abisko and Šumava do not tell the same carbon or competitive story. Shrub and forest plots at Abisko held less SOC and respired about three times heath rates per kilogram of organic carbon. Šumava emphasises species replacement (beech gaining, spruce declining under acid/drought, fir recovering with cleaner air) rather than a measured SOC collapse along a shrub transect.
Evidence for the claim as stated.
Open questions
Tensions this paper is part of
From concept pages' “where studies disagree.” Disagreement means the same question; scope means different assays, populations, or outcomes.
Mixed-effects and adjacent hierarchical papers here are not one invasive-species result. Children's BMI growth is a traffic-pollution question (non-freeway NOₓ associated; freeway NOₓ not). Abisko space-for-time finds SOC falling from 9.01 to 4.51 kg m⁻² heath to forest as a shrub-expansion analogue. Šumava tree rings track beech versus spruce under shifting air chemistry in 35 trees. The brown-trout PVA is a suppression forecast (QE in 5.7–6.3 years; 29% if age-0 methods are skipped), not a mixed model of field counts proving those rates. The method label mixes four questions.
Even within vegetation change, Abisko and Šumava do not tell the same carbon or competitive story. Shrub and forest plots at Abisko held less SOC and respired about three times heath rates per kilogram of organic carbon. Šumava emphasises species replacement (beech gaining, spruce declining under acid/drought, fir recovering with cleaner air) rather than a measured SOC collapse along a shrub transect.
Related papers in this topic
Same topic cluster — not a recommendation engine.