Centre for Earth, Planetary, Space and Astronomical Research, Department of Environment, Earth and Ecosystems, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
Nature. 2013 Jan 31;493(7434):660-3. doi: 10.1038/nature11818.
Tropical peatlands contain one of the largest pools of terrestrial organic carbon, amounting to about 89,000 teragrams (1 Tg is a billion kilograms). Approximately 65 per cent of this carbon store is in Indonesia, where extensive anthropogenic degradation in the form of deforestation, drainage and fire are converting it into a globally significant source of atmospheric carbon dioxide. Here we quantify the annual export of fluvial organic carbon from both intact peat swamp forest and peat swamp forest subject to past anthropogenic disturbance. We find that the total fluvial organic carbon flux from disturbed peat swamp forest is about 50 per cent larger than that from intact peat swamp forest. By carbon-14 dating of dissolved organic carbon (which makes up over 91 per cent of total organic carbon), we find that leaching of dissolved organic carbon from intact peat swamp forest is derived mainly from recent primary production (plant growth). In contrast, dissolved organic carbon from disturbed peat swamp forest consists mostly of much older (centuries to millennia) carbon from deep within the peat column. When we include the fluvial carbon loss term, which is often ignored, in the peatland carbon budget, we find that it increases the estimate of total carbon lost from the disturbed peatlands in our study by 22 per cent. We further estimate that since 1990 peatland disturbance has resulted in a 32 per cent increase in fluvial organic carbon flux from southeast Asia--an increase that is more than half of the entire annual fluvial organic carbon flux from all European peatlands. Our findings emphasize the need to quantify fluvial carbon losses in order to improve estimates of the impact of deforestation and drainage on tropical peatland carbon balances.
热带泥炭地拥有最大的陆地有机碳储量之一，约为 89000 太克（1 太克为 10 亿公斤）。其中约 65%的碳储量位于印度尼西亚，这里广泛的人为退化形式包括森林砍伐、排水和火灾，正在将其转化为全球重要的大气二氧化碳源。在这里，我们量化了来自完整泥炭沼泽森林和过去受到人为干扰的泥炭沼泽森林的河流有机碳的年排放量。我们发现，受干扰的泥炭沼泽森林的总河流有机碳通量比完整的泥炭沼泽森林高出约 50%。通过对溶解有机碳（占总有机碳的 91%以上）的碳-14 测年，我们发现完整泥炭沼泽森林中溶解有机碳的淋溶主要来自最近的初级生产（植物生长）。相比之下，受干扰的泥炭沼泽森林中的溶解有机碳主要来自泥炭柱深处的古老（数百年到数千年）碳。当我们将河流碳损失项纳入泥炭地碳预算中时，这通常会被忽略，我们发现这会使我们研究中受干扰泥炭地的总碳损失估计增加 22%。我们进一步估计，自 1990 年以来，泥炭地的干扰导致东南亚河流有机碳通量增加了 32%，这一增加超过了所有欧洲泥炭地的年河流有机碳通量的一半。我们的研究结果强调了量化河流碳损失的必要性，以提高对森林砍伐和排水对热带泥炭地碳平衡影响的估计。
