全球变化背景下北方泥炭地释放溶解有机碳的驱动机制  

Driving mechanisms for the DOC increases in surface waters released from Northern Peatlands under global change

作　　者：向武[1] Jiasong Fang 万翔[1] 贺灵[1] 孙兴庭[1] 闭向阳[1] 

机构地区：[1]生物地质和环境地质国家重点实验室；中国地质大学武汉,湖北武汉430074 [2]Department of Natural Sciences, Hawaii Pacific University, 45-045 Kamehameha Hwy. Kanoehe, HI 96744, USA

出　　处：《地学前缘》2011年第6期72-78,共7页Earth Science Frontiers

基　　金：国家自然科学基金项目“泥炭沼泽土壤热响应过程中酚类物质的作用及其机制”(40772205)

摘　　要：泥炭地(peatland)是一类储碳效率很高的特殊陆地生态系统,其碳储量约占全球土壤碳库的近1/3,对全球碳循环有着举足轻重的作用。有证据表明在过去20余年,北半球大范围的天然水体中溶解有机碳的浓度呈显著增升趋势。普遍认为与全球变化背景下北方泥炭地大规模释放溶解有机碳有关,但其驱动机制尚不十分清楚。已经提出的具有代表性的机制包括:(1)温度升高驱动机制;(2)大气CO2浓度增加驱动机制;(3)水文变化驱动机制;(4)酸沉降变化驱动机制等。但上述学说都存在一些不足,尚不能很好解释DOC增升现象。通过综合分析国内外已有成果,认为引起DOC增升的机制存在复杂多样性,但全球变暖引发的水热条件变化可能是最主要的驱动因素。Peatlands are the most efficient terrestrial ecosystems in storing carbon, which contain approximately one third of the world＇s soil carbon pool and play an important role in global carbon cycling. During the last two decades, increases in dissolved organic carbon （DOC） concentrations have been observed in freshwaters across large areas of Northern Hemisphere. It is generally considered to be related to large scale DOC; releasing from Northern Peatlands. Several hypotheses have been put forward as potential driving mechanisms for the increase in DOC, including （1） changes in temperature; （2）elevated CO2 concentrations; （3） changes in Hydrological processes; （4） Decrease in sulphur deposition. However, none of the proposed hypotheses is completely convincing. After reviewing previous studies, we proposed that the combining forces of temperature and hydrological processes under global change possibly are the main dominant drivers of DOC change, though multiple mechanisms for rising DOC exist.

关 键 词：驱动机制 溶解有机碳 泥炭地 全球变化 

分 类 号：P595[天文地球—地球化学]