Abstract
Salinization in the Yellow River delta poses a challenge for agriculture, but nitrogen-fixing bacteria can improve soil nitrogen content and enhance plant growth under salt stress. This study focuses on the salt-tolerant plant Suaeda salsa, analyzing its plant traits and the diversity of nitrogen-fixing bacteria in its rhizosphere using the nifH gene. Results show a gradual decline in plant height, fresh weight, and microbial diversity from inland to coastal areas. The rhizosphere bacteria, mainly from the Proteobacteria and Cyanobacteria phyla, are influenced by environmental factors such as alkali hydrolyzed nitrogen (AN), soil organic matter (SOM), electrical conductivity (EC), and pH. The rhizosphere serves as a microbial resource with potential agricultural applications for saline soils.