The soil carbon dilemma: Shall we hoard it or use it?
The soil carbon dilemma: Shall we hoard it or use it?
复制标题
DOI：
10.1016/j.soilbio.2005.10.008
复制
发表时间：
2006-03-01
影响因子：
9.7
通讯作者：
Janzen, HH
中科院分区：
文献类型：
--
作者：
Janzen, HH
大气中二氧化碳浓度的迅速上升引发了一系列关于土壤潜在碳（C）“沉降”的研究。在土壤中封存碳通常被视为“双赢”的主张；它不仅可以去除空气中多余的二氧化碳，还可以通过增加有机物质（生物群的能量和营养来源）来改善土壤。但从生物学角度来说，有机物在腐烂时才最有用。因此，我们面临着一个困境：我们能否既保护有机物又从其腐烂中获利？或者我们必须选择其中之一？在这篇文章中，我部分地从历史的角度思考了首先构建土壤 C，然后腐烂（失去）它的优点。然后，我考虑应计与衰减之间的明显权衡，并思考如何解决或缓解这一困境。这些初出茅庐的想法主要是为了引发更有成效的辩论，包括：寻找增加土壤碳输入的方法；寻求优化衰减时间；从生态系统的角度更好地理解 C 的流动，而不仅仅是存量。碳封存是一个合理且有价值的目标。但土壤有机质远不止是储存过量二氧化碳的潜在储罐；它是碳原子的无情流动，通过无数的溪流——有些快，有些慢——在生态系统中流动，驱动沿途的生物过程。现在，当我们的目标是重新获得一些失去的碳时，我们可能需要新的方式来思考土壤碳动态，并调整它们以适应我们生态系统预期的服务。当我们考虑即将到来的全球变化即将带来的压力时，这一目标可能需要更多的生物学以及其他学科，显得尤为紧迫。 Crown 版权所有 (c) 2005 由 Elsevier Ltd 出版。保留所有权利。
Rapidly rising concentrations of atmospheric CO2 have prompted a flurry of studies on soils as potential carbon (C) 'sinks'. Sequestering C in soils is often seen as a 'win-win' proposition; it not only removes excess CO2 from the air, but also improves soils by augmenting organic matter, an energy and nutrient source for biota. But organic matter is most useful, biologically, when it decays. So we face a dilemma: can we both conserve organic matter and profit from its decay? Or must we choose one or the other? In this essay, I contemplate the merits, first of building soil C and then of decaying (losing) it, partly from a historical perspective. I then consider the apparent trade-off between accrual and decay, and reflect on how the dilemma might be resolved or assuaged. These fledgling thoughts, offered mostly to stir more fruitful debate, include: finding ways to increase C inputs to soil; seeking to optimize the timing of decay; and understanding better, from an ecosystem perspective, the flows of C, rather than only the stocks. Carbon sequestration is a sound and worthy goal. But soil organic matter is far more than a potential tank for impounding excess CO2; it is a relentless flow of C atoms, through a myriad of streams-some fast, some slow-wending their way through the ecosystem, driving biotic processes along the way. Now, when we aim to regain some of the C lost, we may need new ways of thinking about soil C dynamics, and tuning them for the services expected of our ecosystems. This objective, perhaps demanding more biology along with other disciplines, is especially urgent when we contemplate the stresses soon to be imposed by coming global changes. Crown Copyright (c) 2005 Published by Elsevier Ltd. All rights reserved.