Priming of soil organic carbon decomposition induced by exogenous organic carbon input a meta-analysis

• Published in: Plant and soil Vol. 443; no. 1/2; pp. 463 - 471
• Main Authors: Sun, Zhaolin, Liu, Shengen, Zhang, Tianan, Zhao, Xuechao, Chen, Shi, Wang, Qingkui
• Format: Journal Article
• Language: English
• Published: Cham Springer Science + Business Media 01.10.2019; Springer International Publishing; Springer; Springer Nature B.V
• Subjects: Agricultural land; Analysis; Biomedical and Life Sciences; Carbon; Carbon 13; Carbon 14; Carbon content; Climate change; Decomposition; Ecology; Forest soils; Global temperature changes; Life Sciences; Meta-analysis; Nitrogen; Organic carbon; Organic soils; Plant Physiology; Plant Sciences; Priming; REGULAR ARTICLE; Soil acidity; Soil chemistry; Soil conditions; Soil pH; Soil properties; Soil Science & Conservation; Soil temperature; Soils; Terrestrial ecosystems; Canada; China; Soil property; Soil organic carbon decomposition; Priming effect; Carbon turnover; Incubation condition
• DOI: 10.1007/s11104-019-04240-5
• ISSN: 0032-079X

Background and aims Priming 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. Methods Using 2048 experimental comparisons compiled from 94 incubation studies with stable ( 13 C) or radioactive ( 14 C) 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. Results The 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. Conclusions Our 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.