Terrestrialization of sediment bacterial assemblages when temporary rivers run dry

Area of Science:

• Ecology
• Microbiology
• Environmental Science

Background:

• Riverine bacterial communities are shaped by dispersal and local environmental selection.
• Temporary rivers experience seasonal drying and rewetting, influencing habitat connectivity and microbial composition.

Purpose of the Study:

• To compare temporal and spatial changes in bacterial communities in streambed and floodplain habitats of permanent and intermittent river segments.
• To understand the role of environmental selection and hydrological dynamics in shaping bacterial assemblages in temporary rivers.

Main Methods:

• Tracking and comparing bacterial community composition over time and space.
• Analyzing streambed sediments and floodplain habitats across permanent and intermittent river sections.

Main Results:

• Environmental selection is a key factor in bacterial community assembly in both permanent and temporary river segments.
• Specific environmental features act as filters, favoring distinct bacterial taxa in isolated pools and dry areas.
• Temporary rivers show an increasing incorporation of terrestrial microorganisms adapted to desiccation.

Conclusions:

• Distinct environmental filters shape bacterial communities at local scales in river systems.
• Climate change-induced drying trends in temporary rivers promote the integration of terrestrial microbes.
• The incorporation of terrestrial microorganisms is a significant adaptive response of temporary river ecosystems to climate change.