Priming of soil organic carbon decomposition induced by exogenous organic carbon input: a meta-analysis
Priming of soil organic carbon decomposition induced by exogenous organic carbon input: a meta-analysis
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外源有机碳输入诱导土壤有机碳分解的引发：荟萃分析
DOI：
10.1007/s11104-019-04240-5
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发表时间：
2019-10-01
期刊：
影响因子：
4.9
通讯作者：
Wang, Qingkui
中科院分区：
文献类型：
--
作者：
Sun, Zhaolin;Liu, Shengen;Wang, Qingkui
背景与目的外源有机碳诱导土壤有机碳分解的启动效应是调节土壤碳循环的重要生态过程。本研究的目的是在全球尺度上评估不同生态系统间有机碳排放的差异，探索影响生态系统碳排放方向和大小的因素。方法利用稳定碳(13C)和放射性碳(14C)碳同位素技术在94个孵化研究中收集的2048个实验数据，对不同陆地生态系统中外源有机碳输入对自然有机碳分解(PE)的影响进行荟萃分析。结果外源有机碳显著促进土壤有机碳分解47.5%(即正向有机碳)，其中农田土壤最高(60.9%)，森林土壤最低(26.2%)。PE强度随土壤有机碳含量、土壤全氮含量、土壤C/N、培养时间和培养温度的增加而降低，随外源有机C添加量和土壤pH的增加而增加。土壤PE不受外源有机C复杂性的影响。结论正PE是陆地生态系统中普遍存在的一种现象，其大小与土壤性质和实验条件密切相关。这些发现可能有助于理解气候变化情景下土壤碳启动及其对土壤碳平衡的影响。
Background and aimsPriming effect (PE) of soil organic carbon (SOC) decomposition induced by exogenous organic C is an important ecological process in regulating the soil C cycle. The objective of this study was to evaluate how the PE varied among different ecosystems at the global scale and explore factors that drive the direction and magnitude of the PE.MethodsUsing 2048 experimental comparisons compiled from 94 incubation studies with stable (13C) or radioactive (14C) carbon isotopic techniques, we performed a meta-analysis on the effect of exogenous organic C input on native SOC decomposition (i.e., PE) across multiple terrestrial ecosystems. In particular, the linear mixed-effect model was used to examine the relationship between the PE and potential influencing factors.ResultsThe addition of exogenous organic C significantly enhanced native SOC decomposition by 47.5% (i.e., positive PE), with the highest value in cropland soils (60.9%) and the lowest value in forest soils (26.2%). The intensity of the PE decreased with increasing SOC content, soil total nitrogen content, soil C/N, incubation duration, and incubation temperature, but increased with increasing exogenous organic C addition rate and soil pH. Soil PE was not affected by the complexity of exogenous organic C.ConclusionsOur results indicate that positive PE is a widespread phenomenon in terrestrial ecosystems, and that the magnitude is closely related to soil properties and experimental conditions. These findings may be useful for understanding soil C priming and the effect on soil C balance under climate change scenarios.