TY - JOUR

T1 - Response of topsoil Fe-bound organic carbon pool and microbial community to Spartina alterniflora invasion in coastal wetlands

AU - Lin, Meifen

AU - Chen, Yu

AU - Cheng, Liwen

AU - Zheng, Yi

AU - Wang, Weiqi

AU - Sardans, Jordi

AU - Song, Zhaoliang

AU - Guggenberger, Georg

AU - Zou, Yuanchun

AU - Ding, Xueli

AU - Tariq, Akash

AU - Zeng, Fanjiang

AU - Fahad Alrefaei, Abdulwahed

AU - Peñuelas, Josep

N1 - Funding Information: The authors would like to thank Haifeng Fu, Dengzhou Gao, Xiao Lin, Jiafang Huang for their assistance with field sampling and laboratory analysis. Funding was provided by the National Science Foundation of China ( 42141014 ; 41901111 ; 42077086 ), Ministry of Science and Technology Basic Work Special Project of China (2013FY111805), the Natural Science Foundation of Fujian Province (2020J01188; 2021J06019), the Spanish Government grants PID2019-110521GB-I00 and PID2020115770RB-I, the Fundación Ramón Areces grant ELEMENTAL-CLIMATE, and the Catalan Government grant SGR 2017-1005. We extend our appreciation to the Researchers Supporting Project (no. RSP2023R218), King Saud University, Riyadh, Saudi Arabia.

PY - 2023/11

Y1 - 2023/11

N2 - Wetland ecosystems have dual functions as both carbon (C) sources and C sinks, playing a vital role in the world's C budget. Wetlands are prone to suffer from plant invasions, and for example, Spartina alterniflora, a well-known invasive species, has rapidly expanded in coastal areas of Asia since 1979 and altered the C cycles in coastal wetland ecosystems. Fe(III) oxides are critical in the OC storage by formation of Fe-bound organic carbon (Fe-OC). But the impact of the invasion by S. alterniflora in coastal wetlands on the formation and stabilization of Fe-OC is poorly known. Herein, we assessed soil Fe species contents, Fe-OC pool, and the microbial communities associated with these processes in seven wetlands dominated by both native (Kandelia obovate, Avicennia marina and Phragmites australis) and invasive (S. alterniflora) plants. Our results showed that organical complexed Fe (Fep) concentration and Fe complexing index under S. alterniflora community were lower than that under native communities. Soil Fe-OC concentration and molar OC:Fe ratio decreased (35.9% and 29.3%, respectively) after S. alterniflora invasion in coastal wetlands, while the abundance of FeRB increased by 78.6%. The invasion of S. alterniflora increased soil water content while decreased bulk density, and these changes could have important effects on Fe species and FeRB abundance. Moreover, Fe-OC was positive correlated with soil organic carbon (SOC), Fep, and Fe(III), indicating that SOC and Fe(III) concentrations directly affect the formation of Fe-OC. FeRB reacted on the combination of Fe (hydr-) oxides and SOC to indirectly affect Fe-OC through dissimilatory Fe reduction, which further determined the stabilization and mineralization of SOC. Taken together, the invasion of S. alterniflora hindered the generation and accumulation of soil Fe-OC pool weakening the stabilization of SOC in coastal wetlands. Therefore, the conservation and restoration of mangroves and other coastal wetlands provide a promising strategy for SOC sequestration and climate change mitigation.

AB - Wetland ecosystems have dual functions as both carbon (C) sources and C sinks, playing a vital role in the world's C budget. Wetlands are prone to suffer from plant invasions, and for example, Spartina alterniflora, a well-known invasive species, has rapidly expanded in coastal areas of Asia since 1979 and altered the C cycles in coastal wetland ecosystems. Fe(III) oxides are critical in the OC storage by formation of Fe-bound organic carbon (Fe-OC). But the impact of the invasion by S. alterniflora in coastal wetlands on the formation and stabilization of Fe-OC is poorly known. Herein, we assessed soil Fe species contents, Fe-OC pool, and the microbial communities associated with these processes in seven wetlands dominated by both native (Kandelia obovate, Avicennia marina and Phragmites australis) and invasive (S. alterniflora) plants. Our results showed that organical complexed Fe (Fep) concentration and Fe complexing index under S. alterniflora community were lower than that under native communities. Soil Fe-OC concentration and molar OC:Fe ratio decreased (35.9% and 29.3%, respectively) after S. alterniflora invasion in coastal wetlands, while the abundance of FeRB increased by 78.6%. The invasion of S. alterniflora increased soil water content while decreased bulk density, and these changes could have important effects on Fe species and FeRB abundance. Moreover, Fe-OC was positive correlated with soil organic carbon (SOC), Fep, and Fe(III), indicating that SOC and Fe(III) concentrations directly affect the formation of Fe-OC. FeRB reacted on the combination of Fe (hydr-) oxides and SOC to indirectly affect Fe-OC through dissimilatory Fe reduction, which further determined the stabilization and mineralization of SOC. Taken together, the invasion of S. alterniflora hindered the generation and accumulation of soil Fe-OC pool weakening the stabilization of SOC in coastal wetlands. Therefore, the conservation and restoration of mangroves and other coastal wetlands provide a promising strategy for SOC sequestration and climate change mitigation.

KW - Carbon-cycle

KW - Coastal wetlands

KW - Fe-bound organic carbon

KW - Plant invasion

KW - Spartina alterniflora

UR - http://www.scopus.com/inward/record.url?scp=85166964685&partnerID=8YFLogxK

U2 - 10.1016/j.catena.2023.107414

DO - 10.1016/j.catena.2023.107414

M3 - Article

AN - SCOPUS:85166964685

VL - 232

JO - CATENA

JF - CATENA

SN - 0341-8162

M1 - 107414

ER -