River bed carbon and nitrogen cycling: state of play and some new directions.
River bed carbon and nitrogen cycling: state of play and some new directions.
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DOI：
10.1016/j.scitotenv.2011.10.074
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发表时间：
2012-09
期刊：
影响因子：
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通讯作者：
M. Trimmer;J. Grey;C. Heppell;A. Hildrew;K. Lansdown;H. Stahl;G. Yvon‐Durocher
中科院分区：
文献类型：
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作者：
M. Trimmer;J. Grey;C. Heppell;A. Hildrew;K. Lansdown;H. Stahl;G. Yvon‐Durocher
淡水作为全球二氧化碳和甲烷预算的主要参与者的重要性最近得到了强调。特别是，河流显然不仅仅是将碳从集水区输送到海岸的惰性管道，但总体而言，它们的代谢活动转化了它们输送的碳的相当大一部分。此外，氮也在循环，有时与碳紧密结合，在集水区和海岸之间有相当数量的氮被“同化”。然而，在我们的知识的意义上的交换和河流及其集水区之间的相互作用，特别是通过潜流沉积物介导的相互作用的意义的不足，仍然是显而易见的。从量化小样本砾石的氧气消耗量的卑微开始，到碳和氮的范围尺度转化的综合测量，我们对河流中这两种宏观元素循环的理解在过去几十年中有了显着提高。然而，最近在一系列水生生态系统中发现了氮和碳循环的新代谢途径，这突出了对新方向和真正多学科方法的需求，以量化河流中的碳和氮通量。
The significance of freshwaters as key players in the global budget of both carbon dioxide and methane has recently been highlighted. In particular, rivers clearly do not act simply as inert conduits merely piping carbon from catchment to coast, but, on the whole, their metabolic activity transforms a considerable fraction of the carbon that they convey. In addition, nitrogen is cycled, sometimes in tight unison with carbon, with appreciable amounts being ‘denitrified’ between catchment and coast. However, shortfalls in our knowledge about the significance of exchange and interaction between rivers and their catchments, particularly the significance of interactions mediated through hyporheic sediments, are still apparent. From humble beginnings of quantifying the consumption of oxygen by small samples of gravel, to an integrated measurement of reach scale transformations of carbon and nitrogen, our understanding of the cycling of these two macro elements in rivers has improved markedly in the past few decades. However, recent discoveries of novel metabolic pathways in both the nitrogen and carbon cycle across a spectrum of aquatic ecosystems, highlights the need for new directions and a truly multidisciplinary approach to quantifying the flux of carbon and nitrogen through rivers.