Estimating soil C loss potentials from the C to N ratio
Estimating soil C loss potentials from the C to N ratio
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DOI：
10.1016/j.soilbio.2007.10.002
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发表时间：
2008-03
影响因子：
9.7
通讯作者：
I. Thomsen;B. M. Petersen;S. Bruun;L. S. Jensen;B. Christensen
中科院分区：
文献类型：
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作者：
I. Thomsen;B. M. Petersen;S. Bruun;L. S. Jensen;B. Christensen
在- 100hPa、20℃条件下，37份黏土含量为4 ~ 40%、碳氮比为8 ~ 20的耕层土壤样品（0 ~ 20cm），培养238d。105 ~ 147 d和0 ~ 238 d的CO2-C变化与土壤碳氮比呈幂函数关系。我们假设存在一个土壤碳氮比的阈值，低于该阈值，CO2-C的演化保持不变。两个潜伏期的土壤C / N阈值均为9.7，该函数预测当土壤C / N比接近14时，CO2-C演化减半。Springob和Kirchmann获得的数据[Springob， G., Kirchmann， H., 2002]。特定历史土地利用富c砂质有机质层含有大量难降解有机质。土壤化学学报（自然科学版），34(2):571 - 581。]显示出类似的关系，但C to N的阈值为10.8。我们认为，土壤C氮比与土壤培养期间CO2-C损失之间建立的关系代表了在更一般水平上预测土壤C损失潜力的一种简单但有用的措施。
Thirty-seven arable soil samples (0–20cm depth) ranging in clay content from 4 to 40% and in C to N ratio from 8 to 20 were incubated at −100hPa and 20°C for 238days. The CO2-C evolved during days 105–147 and days 0–238 was related to the soil C to N ratio by a power function. We hypothesized the existence of a threshold value for the soil C to N ratio below which CO2-C evolution remains constant. A soil C to N threshold value of 9.7 was estimated for both incubation periods and the function predicted that the CO2-C evolution was halved when the soil C to N ratio approached 14. Data obtained by Springob and Kirchmann [Springob, G., Kirchmann, H., 2002. C-rich sandy Ap horizons of specific historical land-use contain large fractions of refractory organic matter. Soil Biology & Biochemistry 34, 1571–1581.] showed a similar relationship, but with a C to N threshold value of 10.8. We suggest that the relationship established between the C to N ratio of a soil and its CO2-C loss during incubation represents a simple but useful measure for predicting soil C loss potentials on a more general level.