Plant invasions disrupt soil carbon balance in tropical coral islands, new study reveals
image: Effects of plant invasion on soil C pools were highly context dependent. The trade-off between SOC and SIC weakened the response of the overall soil C pool to plant invasions and microbial-derived C mediated the response of the soil C pool to plant invasion.
Credit: Tengteng Li, Biyue Yan, Hongyue Cai, Zhijian Mou, Luhui Kuang, Jing Zhang, Wenjia Wu, Yue Li, Jun Wang, Hongfang Lu, Shuguang Jian, Hai Ren, Zhanfeng Liu
Date: April 22, 2026
Guangzhou, China: A new study published in Biological Diversity uncovered critical shifts in soil carbon dynamics driven by invasive plants on tropical coral islands. While total soil carbon remains unchanged, invasive species trigger a harmful trade-off between soil organic carbon (SOC) and soil inorganic carbon (SIC), threatening long-term soil health and ecosystem function.
Invasive Plants Reduce Native Biomass but Preserve Total Soil Carbon
Led by a team from the South China Botanical Garden, Chinese Academy of Sciences, the research focused on three widespread invaders—Cassytha filiformis, Eupatorium odoratum, and Wedelia biflora—across the Paracel Islands. Results showed plant invasions significantly reduced native vegetation biomass, yet total soil carbon storage stayed stable because increased SIC compensated for declining SOC.
Microbial Carbon Responses Vary by Invasive Species and Season
The team measured soil carbon pools, microbial indicators, and environmental factors in both dry and wet seasons. Invasive plants lowered soil microbial-derived carbon, including amino sugars and glomalin-related soil proteins, but boosted their relative contribution to SOC. Effects varied by species and season: E. odoratum and W. biflora strongly reduced microbial carbon in the wet season, while C. filiformis mainly impacted microbial carbon in the dry season.
SOC Loss Undermines Soil Function Despite Stable Total Carbon
Random forest and structural equation modeling revealed total nitrogen, total phosphorus, and soil enzymes as key drivers of SOC and SIC changes. Invasion intensity reduced SOC but promoted SIC through altered soil chemistry and microbial activity. Despite stable total carbon stocks, the loss of SOC undermines nutrient cycling, water retention, and microbial support—functions SIC cannot replace.
These findings highlight that stable total carbon levels mask serious soil degradation on tropical coral islands. The study calls for species-specific invasive plant management and native vegetation restoration to preserve soil organic carbon and maintain island ecosystem resilience.
The research was supported by the National Natural Science Foundation of China and the National Key Research and Development Program of China.
Original Source
Li, Tengteng, Biyue Yan, Hongyue Cai, Zhijian Mou, Luhui Kuang, Jing Zhang, Wenjia Wu, et al. 2024. “Contrasting responses of soil organic and inorganic carbon pools under plant invasion in tropical coral islands.” Biological Diversity 1(3–4): 124–135.
https://onlinelibrary.wiley.com/doi/10.1002/bod2.12024
Keywords
amino sugars, glomalin-related soil proteins, plant invasions, soil inorganic carbon, soil organic carbon, tropical coral islands
About the Author
Tengteng Li (First Author), PhD, postdoctoral researcher at the South China Botanical Garden, Chinese Academy of Sciences, under the supervision of Professor Zhanfeng Liu. Her research focuses on soil organic carbon sequestration.
Zhanfeng Liu (Corresponding Author), Director of the Research Center for Ecology and Environmental Science, Professor and PhD Supervisor at the South China Botanical Garden, Chinese Academy of Sciences. With prestigious academic awards, he focuses on restoration and soil ecology. His pioneering research on plant–soil–microbe coupling has advanced knowledge of soil microbial responses to climate change, vegetation succession, ecosystem carbon cycling and understory ecological functions.
About the Journal
Biological Diversity (ISSN: 2994-4139) is a new open-access, high-impact, English-language journal, devoted to advancing biodiversity conservation, enhancing ecosystem services, and promoting the sustainable use of resources under global change. It features innovative research addressing the global biodiversity crisis.