Aim: Fresh carbon (C) inputs to the soil can have important consequences for the decomposition rates of soil organic matter (priming effect), thereby impacting the delicate global C balance at the soil–atmosphere interface. Yet, the environmental factors that control soil priming effect intensity remain poorly understood at a global scale. Location: Global. Time period: 1980–2020. Major taxa studied: Soil priming effect intensity. Methods: We conducted a global dataset of CO2 effluxes in 711 pairwise soils with 13C or 14C simple C sources inputs and without C inputs from incubation experiments in which isotope-labelled C was used to quantify fresh C-induced rather than exudate-induced priming. Results: Soil priming effect intensity is predominantly positive. Soil texture and C content were identified as the most important factors associated with priming effects, with sandy soils from tropical and mid-latitudes supporting the highest soil priming effect intensity, and soils with greater C content and fine textures from high latitudes maintaining the lowest soil priming effects. The negative association between C content and soil priming effect intensity was also indirectly driven by changing mean annual temperature, net primary productivity, and fungi : bacteria ratio. Using this information, we generated a global map of soil priming effect intensity, and found that the priming was lower at high latitudes and higher at lower latitudes. Main conclusions: Global patterns of soil priming effect intensity can be predicted using environmental data, with soil texture and C content playing a predominant role in explaining in priming effects. These effects were also indirectly driven by climate, vegetation and soil microbial properties. We present the first global atlas of soil priming effect intensity and advance our knowledge on the potential mechanisms underlying soil priming effect intensity, which are integral to improving the climate change and soil C dynamics components of Earth System models.
|Original language||English (US)|
|Number of pages||9|
|Journal||Global Ecology and Biogeography|
|State||Published - Aug 2022|
Bibliographical noteFunding Information:
This work was financially supported by the National Natural Science Foundation of China (No. 41907031), the China Postdoctoral Science Foundation (No. 2021T140565), the Natural Science Basic Research Plan in Shaanxi Province of China (No. 2020JQ‐272), the Forest and Grass Technology Innovation Development and Research Projects from National Forestry and Grassland Administration (No. 2020132111), the China Postdoctoral Science Foundation (No. 2019M650276), and the Chinese Academy of Sciences ‘Light of West China’ Program for Introduced Talent in the West (No. 31570440). We are grateful to the anonymous referees whose comments and suggestions helped us to enhance the quality of this paper.
© 2022 John Wiley & Sons Ltd.
- climate change
- global atlas
- global drivers
- priming effect intensity
- soil C dynamics
- soil texture