Scientists are tackling “the most profound questions about life itself” with complex computer modeling, billion-year-old bacteria, and old-fashioned fieldwork.
oxygen
Bacteria Battled for Iron in Earth’s Early Oceans
Billions of years ago, iron-oxidizing microbes may have competed for dissolved iron in the ocean, with some strains producing toxic gases that smothered their rivals.
Metallic Nodules Create Oxygen in the Ocean’s Abyss
These nodules, a focus of seabed mining interests, could be natural “geobatteries” and play a larger-than-expected role in the deep-sea ecosystem.
How Great was the “Great Oxidation Event”?
Geochemical sleuthing amid acid mine runoff suggests that scientists should rethink an isotope signal long taken to indicate low levels of atmospheric oxygen in Earth’s deep past.
In Hot Water and Beyond: Marine Extremes Escalate
A new study suggests marine life is increasingly faced with triple-threat events in which extreme water temperature, low oxygen levels, and acidification converge.
How Nutrients Get Back Up to the Surface Ocean
A new dual isotope tracer technique is used to assess the role of a number of poorly understood nutrient supply mechanisms fueling biological productivity in the ocean.
Adding Oxygen to a Lake to Explore Methane Emissions
A rare whole-lake experiment suggests that in some cases, low-oxygen conditions may have a smaller impact on methane release to the atmosphere than previously thought.
Rivers Are Warming Up and Losing Oxygen
Researchers used deep learning to fill in the gaps of “patchy” water quality data, revealing decades-long trends toward warmer and less oxygenated rivers that could have worrisome consequences.
Evidence of Earth’s Oldest Glaciers Found in South Africa
The ancient glaciers hint at an Archaean Earth that may have looked similar in some ways to our own time.
Hypoxia Affects One in Eight Rivers Worldwide
A global study found dangerously low levels of dissolved oxygen in rivers around the world. The true prevalence of hypoxia is probably even higher.