[A-CG31] 北極域の科学

[ACG31-P04] アラスカの陸域生態系における土壌炭素のダイナミクスのシミュレーション

*王 新¹、横沢 正幸²、荒木田 葉月³、森 健介⁴、伊勢 武史⁵、近藤 美由紀⁶、内田 昌男⁶、串田 圭司⁷、戸田 求¹ (1.広島大学、2.静岡大学、3.理化学研究所、4.カルガリー大学、5.京都大学、6.国立環境研究所、7.日本大学)

A large amount of soil organic carbon (SOC) is stored in high-latitude boreal permafrost regions, accounting for twice as much as is in the atmosphere at present. In those regions, climate warming has often caused disturbances that may accelerate the rate of permafrost thaw and change SOC dynamics in both organic and mineral soils. In this study, we used a soil carbon dynamics model named Physical and Biogeochemical Soil Dynamics Model to examine how climate-induced disturbances could change SOC pools in the boreal forest and tundra terrestrial ecosystems in Alaska, especially focusing on the effect of fire disturbances on the permafrost soil layers. The results showed that the fire disturbance would reduce SOC stores substantially associated with the fire-induced thawing of permafrost. It is suggested that the vulnerability of the SOC stocks in the boreal region as affected by future warming is closely linked to the sensitivity of permafrost to wildfire disturbance.