Abstract
Amazonian peatlands store a large amount of soil organic carbon (SOC), and its fate under a future changing climate is unknown. Here, we use a process-based peatland biogeochemistry model to quantify the carbon accumulation for peatland and nonpeatland ecosystems in the Pastaza-Marañon foreland basin (PMFB) in the Peruvian Amazon from 12,000 y before present to AD 2100. Model simulations indicate that warming accelerates peat SOC loss, while increasing precipitation accelerates peat SOC accumulation at millennial time scales. The uncertain parameters and spatial variation of climate are significant sources of uncertainty to modeled peat carbon accumulation. Under warmer and presumably wetter conditions over the 21st century, SOC accumulation rate in the PMFB slows down to 7.9 (4.3–12.2) g·C·m−2·y−1 from the current rate of 16.1 (9.1–23.7) g·C·m−2·y−1, and the region may turn into a carbon source to the atmosphere at −53.3 (−66.8 to −41.2) g·C·m−2·y−1 (negative indicates source), depending on the level of warming. Peatland ecosystems show a higher vulnerability than nonpeatland ecosystems, as indicated by the ratio of their soil carbon density changes (ranging from 3.9 to 5.8). This is primarily due to larger peatlands carbon stocks and more dramatic responses of their aerobic and anaerobic decompositions in comparison with nonpeatland ecosystems under future climate conditions. Peatland and nonpeatland soils in the PMFB may lose up to 0.4 (0.32–0.52) Pg·C by AD 2100 with the largest loss from palm swamp. The carbon-dense Amazonian peatland may switch from a current carbon sink into a source in the 21st century.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 12407-12412 |
| Number of pages | 6 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Volume | 115 |
| Issue number | 49 |
| DOIs | |
| State | Published - Dec 4 2018 |
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Keywords
- Carbon
- Climate
- Modeling
- Peatland
- Simulation
ASJC Scopus subject areas
- General
Cite this
Potential shift from a carbon sink to a source in Amazonian peatlands under a changing climate. / Wang, Sirui; Zhuang, Qianlai; Lähteenoja, Outi; Draper, Frederick C.; Cadillo-Quiroz, Hinsby.
In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 115, No. 49, 04.12.2018, p. 12407-12412.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Potential shift from a carbon sink to a source in Amazonian peatlands under a changing climate
AU - Wang, Sirui
AU - Zhuang, Qianlai
AU - Lähteenoja, Outi
AU - Draper, Frederick C.
AU - Cadillo-Quiroz, Hinsby
PY - 2018/12/4
Y1 - 2018/12/4
N2 - Amazonian peatlands store a large amount of soil organic carbon (SOC), and its fate under a future changing climate is unknown. Here, we use a process-based peatland biogeochemistry model to quantify the carbon accumulation for peatland and nonpeatland ecosystems in the Pastaza-Marañon foreland basin (PMFB) in the Peruvian Amazon from 12,000 y before present to AD 2100. Model simulations indicate that warming accelerates peat SOC loss, while increasing precipitation accelerates peat SOC accumulation at millennial time scales. The uncertain parameters and spatial variation of climate are significant sources of uncertainty to modeled peat carbon accumulation. Under warmer and presumably wetter conditions over the 21st century, SOC accumulation rate in the PMFB slows down to 7.9 (4.3–12.2) g·C·m−2·y−1 from the current rate of 16.1 (9.1–23.7) g·C·m−2·y−1, and the region may turn into a carbon source to the atmosphere at −53.3 (−66.8 to −41.2) g·C·m−2·y−1 (negative indicates source), depending on the level of warming. Peatland ecosystems show a higher vulnerability than nonpeatland ecosystems, as indicated by the ratio of their soil carbon density changes (ranging from 3.9 to 5.8). This is primarily due to larger peatlands carbon stocks and more dramatic responses of their aerobic and anaerobic decompositions in comparison with nonpeatland ecosystems under future climate conditions. Peatland and nonpeatland soils in the PMFB may lose up to 0.4 (0.32–0.52) Pg·C by AD 2100 with the largest loss from palm swamp. The carbon-dense Amazonian peatland may switch from a current carbon sink into a source in the 21st century.
AB - Amazonian peatlands store a large amount of soil organic carbon (SOC), and its fate under a future changing climate is unknown. Here, we use a process-based peatland biogeochemistry model to quantify the carbon accumulation for peatland and nonpeatland ecosystems in the Pastaza-Marañon foreland basin (PMFB) in the Peruvian Amazon from 12,000 y before present to AD 2100. Model simulations indicate that warming accelerates peat SOC loss, while increasing precipitation accelerates peat SOC accumulation at millennial time scales. The uncertain parameters and spatial variation of climate are significant sources of uncertainty to modeled peat carbon accumulation. Under warmer and presumably wetter conditions over the 21st century, SOC accumulation rate in the PMFB slows down to 7.9 (4.3–12.2) g·C·m−2·y−1 from the current rate of 16.1 (9.1–23.7) g·C·m−2·y−1, and the region may turn into a carbon source to the atmosphere at −53.3 (−66.8 to −41.2) g·C·m−2·y−1 (negative indicates source), depending on the level of warming. Peatland ecosystems show a higher vulnerability than nonpeatland ecosystems, as indicated by the ratio of their soil carbon density changes (ranging from 3.9 to 5.8). This is primarily due to larger peatlands carbon stocks and more dramatic responses of their aerobic and anaerobic decompositions in comparison with nonpeatland ecosystems under future climate conditions. Peatland and nonpeatland soils in the PMFB may lose up to 0.4 (0.32–0.52) Pg·C by AD 2100 with the largest loss from palm swamp. The carbon-dense Amazonian peatland may switch from a current carbon sink into a source in the 21st century.
KW - Carbon
KW - Climate
KW - Modeling
KW - Peatland
KW - Simulation
UR - http://www.scopus.com/inward/record.url?scp=85057611862&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85057611862&partnerID=8YFLogxK
U2 - 10.1073/pnas.1801317115
DO - 10.1073/pnas.1801317115
M3 - Article
C2 - 30455319
AN - SCOPUS:85057611862
VL - 115
SP - 12407
EP - 12412
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 49
ER -