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.
• The functional consequences of these microbiome shifts remain poorly understood.
• Seasonal and El Niño-Southern Oscillation (ENSO) warming mimic predicted climate change impacts on ocean conditions.

Purpose of the Study:

• To quantify changes in microbial genomic diversity and function over an 11-year period.
• To investigate the effects of seasonal and ENSO cycles on marine microbial communities in the California Current.
• To understand how climate-driven changes influence microbiome functional potential and biogeochemical cycling.

Main Methods:

• Long-term monitoring of microbial genomic diversity and function over 11 years.
• Analysis of microbial communities across seasonal and interannual ENSO cycles.
• Quantification of changes in gene content related to nutrient stress and organic carbon degradation.

Main Results:

• Observed seasonal oscillations between large and small genome microbial lineages.
• Identified interannual community shifts correlated with ENSO conditions.
• Biodiversity changes directly translated to oscillations in microbiome functional potential.
• Ocean warming led to reduced iron, increased macronutrient stress genes, and depressed carbon degradation.

Conclusions:

• Microbial community structure and function exhibit consistent responses to climate-driven cycles across different time scales.
• Climate change is driving significant alterations in marine ecosystems and their biogeochemical cycles.
• Understanding these microbial responses is crucial for predicting future ocean health and function.