Shifts in Microbial Community Structure and Co-occurrence Network along a Wide Soil Salinity Gradient.

Area of Science:

• Microbiology
• Soil Science
• Ecology

Background:

• Soil microbial community structure and interactions are influenced by salinity.
• Understanding these responses across diverse climatic regions and salinity levels remains incomplete.

Purpose of the Study:

• To investigate how soil microbial community composition and interactions respond to a wide range of salinity levels in two distinct climatic regions (coastal wetland and arid desert).
• To identify the key environmental factors driving these microbial shifts.

Main Methods:

• Examined microbial community composition in saline soils from coastal wetland and arid desert environments.
• Analyzed the relationships between microbial community structure, soil nutrients, and environmental factors (salinity, water content, pH, TN, SOC).

Main Results:

• Soil salinity negatively affected soil nutrient content.
• Salinity shifted microbial communities from bacteria to archaea dominance.
• Complex archaeal networks were found in low-water medium-salinity soils, while complex bacterial networks were observed in low-water high-salinity soils.
• Salinity, soil water content, pH, total nitrogen, and soil organic carbon were identified as key drivers of microbial community composition.

Conclusions:

• Soil salinity significantly alters microbial diversity, composition, and interactions.
• Salinity directly impacts archaea but indirectly affects bacteria via soil organic carbon.
• pH influences archaea indirectly through total nitrogen and bacteria directly.