Floristic quality assessment of saline-alkali habitats in songnen plain

The Songnen Plain, an important agricultural and ecological region in China, is currently experiencing severe salinization, necessitating an urgent scientific assessment of its saline grassland habitat quality. Floristic Quality Assessment (FQA), a rapid method for evaluating habitat quality based on plant adaptations to their environment, has been successfully applied in various ecosystems. Our objective was to use FQA to assess the habitat quality of the Songnen saline-alkali grassland, ultimately providing a scientific basis for the ecological protection and management of this unique ecosystem. In our study, thirty quadrats were randomly selected for a field survey in the Songnen saline-alkali grassland. Plant species were identified, and coefficients of conservatism were assigned to each. Soil physicochemical properties and plant community diversity were also analyzed across different habitat classes. 101 herbaceous plant species across 78 genera and 31 families were identified in the field study. Habitat quality varied significantly, with 4 quadrats classified as excellent, 8 as good, 11 as fair, and 7 as poor. Significant disparities were observed in plant community diversity and soil physicochemical properties among the different habitat quality categories. The key soil factors that influenced habitat quality were pH, organic matter, and total phosphorus content. In summary, our findings indicate that the overall habitat quality of the Songnen saline-alkali grassland is suboptimal. The application of FQA proved to be an effective tool for assessing the current habitat quality and offered a robust scientific foundation for its ecological restoration and management.