One of the scientific challenges of understanding climate change has been determining the important drivers and metrics of global carbon (C) emissions and C cycling in tropical, subtropical, boreal, subarctic, and temperate peatlands. Peatlands account for 3% of global land cover, yet contain a major reservoir of 550 gigatons (Gt) of soil C, and serve as C sinks for 0.37 Gt of carbon dioxide (CO2) a year. In the United States, temperate peatlands are estimated to store 455 petagrams of C (PgC). There has been increasing interest in the role of wildfires in C cycling and altering peatlands from C sinks to major C sources. We estimated above- and below-ground C emissions from the Pains Bay Fire, a long-duration wildfire (112 days; 18,329 ha) that burned a coastal peatland in eastern North Carolina, USA. Soil C emissions were estimated from pre- and post-burn Light Detection and Ranging (LIDAR) soil elevation data, soils series and C content mapping, remotely sensed soil burn severity, and post-burn field surveys of soil elevation. Total above-ground C emissions from the fire were 2,89,579 t C and 214 t C ha−1 for the 10 vegetation associations within the burn area perimeter. Above-ground sources of C emissions were comprised of litter (69,656 t C), shrub (1,68,983 t C), and foliage (50,940 t C). Total mean below-ground C emissions were 5,237,521 t C, and ranged from 2,630,529 to 8,287,900 t C, depending on organic matter content of different soil horizons within each of the 7 soil series. The mean below-ground C emissions within the burn area were 1,595.6 t C ha−1 and ranged from 629.3 to 2511.3 t C ha−1. In contrast to undisturbed temperate peatlands, human induced disturbances of the natural elevation gradient of the peatland has resulted in increased heterogeneity of floristic variation and assemblages that are a product of the spatial and temporal patterns of the water table level and the surface wetness across peatlands. Human induced changes in surface hydrology and land use influenced the fuel characteristics of natural vegetation and associated soils, thus influencing wildfire risk, behavior, and the resulting C emissions.

中文翻译：

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温带沿海泥炭地野火的碳排放：来自天然植物群落和有机土壤的贡献

理解气候变化的科学挑战之一是确定热带、亚热带、北方、亚北极和温带泥炭地中全球碳 (C) 排放和碳循环的重要驱动因素和指标。泥炭地占全球土地覆盖的 3%，但包含 550 吉吨 (Gt) 的土壤碳的主要库，并作为每年 0.37 吉吨二氧化碳 (CO2) 的碳汇。在美国，温带泥炭地估计可储存 455 拍克的碳 (PgC)。人们越来越关注野火在碳循环和将泥炭地从碳汇改变为主要碳源的作用。我们估计了来自 Pains Bay Fire 的地上和地下 C 排放量，这是一场长期野火（112 天；18,329 公顷），烧毁了美国北卡罗来纳州东部的沿海泥炭地。根据燃烧前和燃烧后光探测和测距 (LIDAR) 土壤高程数据、土壤系列和 C 含量绘图、遥感土壤燃烧严重程度以及燃烧后土壤高程实地调查估算土壤碳排放。对于燃烧区域周边的 10 个植被组合，火灾造成的总地上碳排放量为 2,89,579 吨 C 和 214 吨 C ha-1。碳排放的地上源包括枯枝落叶（69,656 吨 C）、灌木（1,68,983 吨 C）和树叶（50,940 吨 C）。总平均地下碳排放量为 5,237,521 吨 C，范围为 2,630,529 至 8,287,900 吨 C，具体取决于 7 个土壤系列中不同土壤层的有机质含量。燃烧区域内的平均地下碳排放量为 1,595.6 t C ha-1，范围为 629.3 至 2511.3 t C ha-1。与未受干扰的温带泥炭地相比，人类对泥炭地自然海拔梯度的干扰导致植物区系变异和组合的异质性增加，这是地下水位水平和整个泥炭地表面湿度的时空模式的产物。人类引起的地表水文和土地利用变化影响了自然植被和相关土壤的燃料特性，从而影响了野火风险、行为和由此产生的碳排放。