Possible effect of soil organic carbon on its own turnover: A negative feedback
Possible effect of soil organic carbon on its own turnover: A negative feedback
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DOI：
10.1016/j.soilbio.2013.11.017
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发表时间：
2014-02
影响因子：
9.7
通讯作者：
Bingchang Tan;Jianbo Fan;Yuan-qiu He;S. Luo;X. Peng
中科院分区：
文献类型：
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作者：
Bingchang Tan;Jianbo Fan;Yuan-qiu He;S. Luo;X. Peng
土壤固碳在减缓气候变化方面发挥着重要作用，因此，了解土壤有机碳周转和动态的机制至关重要。土壤有机质的腐殖化系数（h）和土壤有机质的分解速率（k）共同控制着土壤有机质的转化，它们受到气候、有机质质量、土壤特性和人类活动等因素的影响。然而，SOC含量随时间而变化，并且迄今为止，SOC含量是否是固有因素还没有被清楚地理解。通过一种新的数学方法，我们发现SOC可能通过负反馈调节自身的周转：h随SOC含量的增加而减小，k随SOC含量的增加而增大。这种反馈是由一系列化学、生物和物理机制引起的。研究表明，土壤有机碳库对气候变化的响应是土壤碳输入水平、温度和土壤有机碳周转负反馈的函数;在土壤有机碳含量较低的地区，应优先施用有机物料，以提高土壤固碳能力。
Soil carbon (C) sequestration plays an important role in mitigating climate change; therefore, it is essential to understand the mechanisms underlying soil organic carbon (SOC) turnover and dynamics. The humification coefficient of input organic materials (h) and the SOC decomposition rate (k) together control the SOC turnover, and they have been well known to be affected by factors including climatic factors, organic material qualities, soil characteristics, and anthropogenic activities. However, the SOC content changes over time, and thus far, whether the SOC content is an inherent factor has not been understood clearly. By using a new mathematical method, we found that SOC is possibly able to regulate its own turnover through a negative feedback:hdecreases andkincreases simultaneously with an increase in the SOC content. This feedback is caused by a series of chemical, biological, and physical mechanisms. We suggest that the response of the SOC pool to climate change is a function of the C input level to soil, temperature, and negative feedback of the SOC turnover; in addition, organic materials should be applied in priority to soils with low SOC content to enhance the soil C sequestration.