Eco-evolutionary strategies drive viral diversification in nutrient-poor soils across elevation gradients

Area of Science:

• Environmental microbiology
• Viral ecology
• Soil science

Background:

• Understanding soil viral community responses to global change is crucial for predicting soil health.
• Viral communities' eco-evolutionary trade-offs and functional traits across environmental gradients are poorly understood.

Purpose of the Study:

• To investigate how soil viral communities and their functions change along an elevation gradient.
• To determine the drivers of viral population differentiation in response to environmental variations.

Main Methods:

• Metavirome sequencing was used along an elevation gradient to analyze viral diversity and populations.
• Field microcosm experiments and global mountain datasets were employed for validation.

Main Results:

• Elevation-driven nutritional constraints, more than climate, significantly differentiated viral populations.
• Increasing elevation led to more lytic viruses, increased functional diversity, and greater phage diversifying selection.
• Phages encoded more stress-tolerant bacterial genes and had a higher proportion of unannotated functions, suggesting a role in host carbon assimilation.

Conclusions:

• Soil viral communities exhibit significant differentiation along elevation gradients, primarily driven by nutritional factors.
• Phages play a crucial role in nutrient-poor environments by influencing host carbon assimilation and adapting to stress.
• These findings provide a foundation for understanding soil virus responses to global change and their ecological roles.