在二氧化碳水平升高的情况下从泥炭地出口溶解有机碳
C Freeman1, N Fenner, N J Ostle
1School of Biological Sciences, University of Wales, Bangor LL57 2UW, UK. c.freeman@bangor.ac.uk
Nature
|July 9, 2004
概括
泥炭地河流中碳的增加并不是由于变暖或降雨量变化. 相反,二氧化碳水平的增加刺激了植物的生长,导致河流中更多的溶解有机碳.
科学领域:
- 环境科学 环境科学
- 生物地质化学生物地质化学
- 气候变化科学 气候变化科学
背景情况:
- 泥炭地储存了重要的全球碳.
- 在排水泥的河流中溶解有机碳 (DOC) 的上升表明潜在的碳储存不稳定.
- 以前涉及变暖和河流排放的假设缺乏解释力.
研究的目的:
- 调查在排水泥的河流中溶解有机碳 (DOC) 度增加的驱动因素.
- 为了测试改变降雨模式影响DOC水平的假设.
- 确定导致多克度上升的主要机制.
主要方法:
- 环境因素的分析,包括温度,河流排放和降雨季节性.
- 对二氧化碳水平的实验操纵,以评估对初级生产率和DOC的影响.
- 同位素追踪以确定DOC的来源.
主要成果:
- 气候变暖和河流排放量的增加并不能充分解释不断上升的DOC趋势.
- 雨量模式的变化,特别是夏季降水,也无法解释观察到的DOC增加.
- 较高的二氧化碳水平显著增加了近期初级生产中产生的DOC的比例 (与对照组相比增加了10倍).
结论:
- 通过二氧化碳促进净初级生产率是泥炭地河流中DOC增加的可能驱动因素.
- 皮特兰DOC度对影响初级生产率的因素比对影响分解的因素更为敏感.
- 了解这些机制对于预测泥炭地碳储存在气候变化下的未来稳定性至关重要.
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