TY - JOUR
T1 - The functional role of arbuscular mycorrhizal fungi in enhancing soil organic carbon stocks and stability in dryland
AU - Li, Meng Ying
AU - Wang, Wei
AU - Yin, Hai Hong
AU - Chen, Yinglong
AU - Ashraf, Muhammad
AU - Tao, Hong Yan
AU - Li, Shi Sheng
AU - Wang, Wen Ying
AU - Yang, Chang Lang
AU - Xiao, Yun Li
AU - Zhu, Li
AU - Xiong, You Cai
PY - 2025/5/1
Y1 - 2025/5/1
N2 - Arbuscular mycorrhizal fungi (AMF) are known to influence soil organic carbon (SOC) stock, but the mechanisms by which they affect SOC stability in the rhizosphere remains poorly understood. To address this gap, a 7-year field observation was conducted in a rainfed dryland maize field, with AMF inoculation, AMF exclusion (only benomyl treatment), and the control (no AMF and no benomyl). AMF introduction increased soil occluded particulate organic carbon (oPOC) and mineral-associated organic carbon (MAOC) contents by 15.6 % and 7.1 %, respectively, compared to the control. However, no significant changes were observed in free particulate organic carbon (fPOC) levels. As expected, AMF exclusion led to a general reduction in SOC content. Analyses of in situ 13C labeling showed that AMF inoculation evidently promoted the retention of 13C in oPOC (13.6 %) and MAOC (5.4 %), thereby enhancing SOC stability. High-throughput sequencing results revealed that AMF inoculation led to significant increases in the diversity and abundance of rhizosphere fungal community, with higher co-occurrence network complexity. Meanwhile, the diversity and abundance of rhizosphere bacterial community were substantially reduced (p < 0.05). Importantly, long-term AMF inoculation was observed to weaken soil N stocks, and inhibit microbial hydrolase secretion for C sources. The findings suggest that AMF inoculation can conserve and stabilize SOC by enhancing fungal community proliferation, while reducing microbial extracellular enzyme activity through soil N depletion. Therefore, AMF can be considered rhizosphere carbon engineer that boost persistent carbon sink in drylands via selectively affecting SOC components. The findings provide new insights into global nature-based carbon neutrality strategies.
AB - Arbuscular mycorrhizal fungi (AMF) are known to influence soil organic carbon (SOC) stock, but the mechanisms by which they affect SOC stability in the rhizosphere remains poorly understood. To address this gap, a 7-year field observation was conducted in a rainfed dryland maize field, with AMF inoculation, AMF exclusion (only benomyl treatment), and the control (no AMF and no benomyl). AMF introduction increased soil occluded particulate organic carbon (oPOC) and mineral-associated organic carbon (MAOC) contents by 15.6 % and 7.1 %, respectively, compared to the control. However, no significant changes were observed in free particulate organic carbon (fPOC) levels. As expected, AMF exclusion led to a general reduction in SOC content. Analyses of in situ 13C labeling showed that AMF inoculation evidently promoted the retention of 13C in oPOC (13.6 %) and MAOC (5.4 %), thereby enhancing SOC stability. High-throughput sequencing results revealed that AMF inoculation led to significant increases in the diversity and abundance of rhizosphere fungal community, with higher co-occurrence network complexity. Meanwhile, the diversity and abundance of rhizosphere bacterial community were substantially reduced (p < 0.05). Importantly, long-term AMF inoculation was observed to weaken soil N stocks, and inhibit microbial hydrolase secretion for C sources. The findings suggest that AMF inoculation can conserve and stabilize SOC by enhancing fungal community proliferation, while reducing microbial extracellular enzyme activity through soil N depletion. Therefore, AMF can be considered rhizosphere carbon engineer that boost persistent carbon sink in drylands via selectively affecting SOC components. The findings provide new insights into global nature-based carbon neutrality strategies.
KW - Drought-hit lands
KW - Microbial community
KW - Mineral-associated organic carbon
KW - Rhizosphere organisms
KW - Soil organic carbon stability
UR - http://www.scopus.com/inward/record.url?scp=85213886311&partnerID=8YFLogxK
U2 - 10.1016/j.still.2024.106443
DO - 10.1016/j.still.2024.106443
M3 - Article
AN - SCOPUS:85213886311
SN - 0167-1987
VL - 248
JO - Soil and Tillage Research
JF - Soil and Tillage Research
M1 - 106443
ER -