Functional type mediates the responses of root litter-driven priming effect and new carbon formation to warming.
Sci Total Environ
; 934: 173203, 2024 Jul 15.
Article
en En
| MEDLINE
| ID: mdl-38754500
ABSTRACT
Input of root litter can alter soil organic carbon (SOC) dynamics via causing priming effect (PE) on native SOC decomposition and forming new SOC. However, it is unknown how functional type mediates the root litter-driven PE and new C formation as well as their response to warming, which are of pivotal for soil C budget. We mixed litter segments of absorptive roots and transport roots from a Chinese fir (Cunninghamia lanceolata) plantation into isotopically distinct soil and incubated at 19°C (local mean annual temperature) and 23°C (warming by 4°C) for 210 days. Cumulative PE was calculated via integrating the instantaneous PE rates during the incubation. And the newly formed root litter-derived SOC (SOCrl) was calculated by measuring the δ13C value of soil at the end of incubation using a two-source mixed model. We found that absorptive roots with faster decomposition rates, caused significantly higher cumulative PE and SOCrl than transport roots. The microbial biomass and enzyme activities involved in C, N and P acquisition were significantly higher in the absorptive- than the transport roots addition treatment, indicating a higher level of microbial activation caused by absorptive roots. Although warming significantly increased the litter decomposition for both of functional types, while just significantly increased the PE of transport roots, indicating a root functional type dependent sensitivity of PE to warming. However, warming had no significant effect on SOCrl either for absorptive roots or for transport roots. As a consequence, warming relatively decreased the net SOC balance (difference between PE and SOCrl) in the transport roots addition treatment. Overall, our study highlights, for the first time, that functional type primarily mediates the response of root litter-driven PE to climate warming but not the new C formation, which may advance our understanding of SOC dynamics in Chinese fir plantation under climate change.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Suelo
/
Carbono
/
Raíces de Plantas
País/Región como asunto:
Asia
Idioma:
En
Revista:
Sci Total Environ
Año:
2024
Tipo del documento:
Article
Pais de publicación:
Países Bajos