| Autor: |
Liu, Yuan, Kumar, Amit, Tiemann, Lisa K., Li, Jie, Chang, Jingjing, Xu, Li, He, Nianpeng |
| Předmět: |
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| Zdroj: |
Journal of Soils & Sediments: Protection, Risk Assessment, & Remediation; Jan2024, Vol. 24 Issue 1, p17-31, 15p |
| Abstrakt: |
Purpose: The purpose of this study was to investigate how changes in substrate availability (stimulating root exudate input) affect the temperature response (Q10) of soil organic carbon (SOC) mineralization across different soil profiles to increase our ability to predict the response of soil organic matter dynamics to climate change. Materials and methods: We sampled the topsoil and subsoil of two typical mineral soil profiles and one buried soil profile. Soils were incubated at 10–25 °C at 0.75 °C intervals, SOC mineralization rates were continuously measured with and without glucose addition, and Q10 was calculated. Results and discussion: Our results showed that Q10 decreased with increasing depth in typical mineral soils, but decreased before increasing with depth in buried soil. As expected, substrate addition significantly increased Q10 across soil depths; however, the magnitude of this increase (ΔQ10) differed with soil depth and type. Unexpectedly, in typical mineral soils, ΔQ10 was higher in topsoil than in subsoils, and vice versa for buried soil. ΔQ10 was negatively correlated with initial soil substrate availability (CAI) and positively correlated with soil inorganic N. Conclusions: Overall, our results suggested that increased substrate availability under climate change scenarios (i.e., increased root exudates with elevated CO2 concentrations) could further strengthen the temperature response of SOC mineralization, especially in soils with high inorganic N content or regions with high N deposition rates. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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