Spartina alterniflora in coastal wetlands: ecological impacts, management trade-offs, and future pathways
Spartina alterniflora, one of the most widespread invasive salt-marsh plants globally, has profoundly altered the structure and functioning of coastal wetlands through its influences on sediment dynamics, biodiversity, biogeochemical cycling, and ecosystem resilience. However, the ecological consequences and management implications of its invasion remain highly controversial because its impacts vary substantially across wetland types, climatic regions, and invasion stages. To clarify the development and emerging directions of S. alterniflora research, this study provides a systematic review of S. alterniflora research, highlighting advances, challenges, and prospects in this field. Bibliometric and quantitative methods assessed research trends, while synthesized ecological findings highlight S. alterniflora’s impacts, such as increased soil carbon sequestration and biodiversity shifts. Literature spanning 1929–2026 from the Web of Science database and Chinese-funded projects recorded in the Fun Research database (1987–2026) formed the basis of the analysis. Bibliometric analysis, keyword co-occurrence clustering, and multiple correspondence analysis were applied to examine knowledge structure, thematic evolution, and research trends. The results demonstrate that S. alterniflora research has evolved from early studies focusing on plant growth, invasion ecology, and salt-marsh dynamics toward increasingly interdisciplinary investigations emphasizing blue carbon, climate change interactions, ecosystem resilience, and adaptive management. Three major thematic domains were identified: invasion ecology and biodiversity responses, biogeochemical cycling and blue carbon processes, and climate-related vulnerability and adaptation research. The ecological impacts of S. alterniflora were found to be strongly context-dependent across salt marshes, mangrove ecosystems, and tidal flats, generating both ecosystem benefits, such as shoreline stabilization and sediment accretion, and ecological risks including biodiversity loss, habitat homogenization, and altered trophic interactions. This review further highlights substantial uncertainties in evaluating the net climatic effects of S. alterniflora invasion due to spatial heterogeneity, greenhouse gas offsets, microbial feedbacks, and limitations in current blue carbon accounting frameworks. Recent advances in remote sensing, unmanned aerial vehicles, machine learning, and molecular ecology are rapidly improving the capacity to monitor invasion dynamics and assess ecosystem responses across multiple spatial and temporal scales. This study emphasizes that S. alterniflora should not be viewed solely as either a harmful invasive species or a beneficial ecosystem engineer, but rather as a complex ecological driver embedded within coupled coastal socio-ecological systems in the Anthropocene. Future research and management should therefore adopt integrated, context-dependent, and adaptive frameworks that simultaneously consider biodiversity conservation, climate mitigation, coastal resilience, and long-term ecosystem sustainability.