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.

亚马逊泥炭地储存了大量的土壤有机碳（SOC），其在未来气候变化下的命运尚不清楚。在这里，我们使用基于过程的泥炭地生物地球化学模型来量化秘鲁亚马逊帕斯塔萨-马拉尼翁前陆盆地 (PMFB) 泥炭地和非泥炭地生态系统从 12,000 年前到公元 2100 年的碳积累。模型模拟表明变暖加速泥炭 SOC 损失，而降水量的增加则加速了泥炭 SOC 在千年时间尺度上的积累。气候的不确定参数和空间变化是模拟泥炭碳积累的不确定性的重要来源。在 21 世纪更温暖且可能更湿润的条件下，PMFB 中的 SOC 累积速率从当前的 16.1 (9.1–23.7) g⋅ 减慢至 7.9 (4.3–12.2) ^g⋅C⋅m −2 ^⋅y −1 C⋅m ⁻² ⋅y ⁻¹，该区域可能在 −53.3 (−66.8 至 −41.2) g⋅C⋅m ⁻² ⋅y ⁻¹处变成大气碳源（负值表示源），具体取决于在变暖的水平上。泥炭地生态系统比非泥炭地生态系统表现出更高的脆弱性，其土壤碳密度变化比率（范围为 3.9 至 5.8）表明了这一点。这主要是由于与未来气候条件下的非泥炭地生态系统相比，泥炭地的碳储量更大，其需氧和厌氧分解的反应更剧烈。到公元 2100 年，PMFB 中的泥炭地和非泥炭地可能会损失高达 0.4 (0.32–0.52) Pg⋅C，其中棕榈沼泽造成的损失最大。碳密集的亚马逊泥炭地可能会从目前的碳汇转变为 21 世纪的碳源。