Climate-driven succession in marine microbiome biodiversity and biogeochemical function

Area of Science:

• Marine microbiology
• Oceanography
• Climate change science

Background:

• Climate-driven environmental cycles significantly impact marine microbiome diversity.
• Microbiome functional responses to these cycles are poorly understood.
• Seasonal and El Niño-Southern Oscillation (ENSO) warming mimic projected climate change impacts on oceans.

Purpose of the Study:

• To quantify microbial genomic diversity and function changes over 11 years.
• To analyze responses to seasonal and ENSO cycles in the California Current.
• To link microbial biodiversity shifts to functional potential changes.

Main Methods:

• 11-year study of microbial genomic diversity and function.
• Analysis of seasonal and ENSO-driven oceanographic cycles.
• Quantification of microbial lineages, functional genes, and biogeochemical indicators.

Main Results:

• Observed seasonal oscillations between large-genome (winter/spring) and small-genome (summer/fall) lineages.
• Identified interannual community shifts correlated with ENSO conditions.
• Ocean warming led to reduced iron, increased macronutrient stress genes, depressed carbon degradation, and higher carbon-to-nutrient ratios.

Conclusions:

• Microbial biodiversity and function exhibit consistent responses to climate-driven cycles across timescales.
• These findings highlight significant climate-driven alterations in marine ecosystems and biogeochemical cycles.
• The California Current microbial ecosystem demonstrates sensitivity to warming and ENSO events.