Ocean acidification may starve diatoms of silicon and threaten fisheries

A 24-year study off Washington state found that as seawater pH fell, the dissolved silicon-to-nitrogen ratio dropped 56% and chlorophyll declined 92%. Silicon is essential to diatoms, which produce about 40% of the ocean's primary production, and their decline could ripple up to herring, salmon and halibut fisheries.

• Silicon-to-nitrogen ratio fell 56% and chlorophyll 92% over 24 years
• Diatoms account for roughly 40% of ocean primary production
• Washington Pacific herring catches declined as the Si:N ratio fell
• Upwelling regions off California, South America and Africa may face similar risk