Distribution of habitat suitability for Suaeda salsa in the Liaohe River Estuary and its relationship with carbon storage.

Suaeda salsa acts as a natural barrier between land and sea in estuarine wetlands while also serving as a significant source of carbon storage. Understanding the synergistic relationship between the spatial distribution of Suaeda salsa habitat suitability and its carbon storage capabilities is essential for guiding ecological restoration and bolstering the carbon sequestration potential of wetlands. Drawing on field survey data from the Liaohe River Estuary wetlands collected in 2021 and 2022, we applied the Maxent model to delineate the spatial distribution of Suaeda salsa habitat suitability. The findings indicate that the principal environmental determinants for the Suaeda salsa community are elevation, soil phosphorus, and sand and soil salt content. Habitats can be divided from into four classes with increasing suitability index: I, II, III, and IV. As the most favorable habitat, class IV spanned 33.07 km and constituted 22.37 % of the area. By integrating remote sensing and ground survey data, a carbon storage evaluation model for Suaeda salsa was developed. This model revealed that the carbon storage within the Liaohe River Estuary reached 8238.18 and 16,194.08 tons in 2021 and 2022, respectively. Finally, the spatial overlay analysis of habitat suitability distribution and carbon storage revealed that an increase in habitat suitability led to an increase in carbon storage in Suaeda salsa, which was also influenced by the surrounding land use types. This work demonstrates a significant positive correlation between habitat suitability and carbon sequestration capacity. In the future, we suggest that ecological restoration projects in the Liaohe Estuary region focus on areas with higher habitat suitability. This study supports the sustainable management of the Suaeda salsa community and provides a theoretical basis for enhancing the carbon sequestration capacity of estuarine wetlands.