Process
Photosynthesis
Using light energy to turn carbon dioxide and water into sugar, releasing oxygen.
Carbon fixed by plants, algae and photosynthetic microbes: about 105 billion tonnes a year worldwide, roughly half on land and half in the ocean.Source: Field et al., 1998
Process
Using light energy to turn carbon dioxide and water into sugar, releasing oxygen.
Organism or group
Microscopic photosynthetic organisms drifting in sunlit water. Ocean producers account for roughly half of the carbon fixed on Earth each year.
Process
Energy enters most ecosystems as sunlight and is lost at each step up a food chain, which limits how many levels it can support.
The explanations on this page are our own summaries of these sources. Follow a link to read the original; if anything here disagrees with it, the original wins. How we choose and check sources.
Field CB, Behrenfeld MJ, Randerson JT, et al. (1998). Science 281:237-240.
Global net primary production of about 105 petagrams of carbon per year, split roughly evenly between land and ocean.