Earth's Systems / Biological processes / Terrestrial ecosystem functioning / Soil formation / Mineral surfaces accumulate and protect organic carbon as soil ages
Mineral surfaces accumulate and protect organic carbon as soil ages
Weathering creates reactive iron, aluminium and short-range-order minerals that bind organic carbon and slow its turnover, so soil carbon storage depends on mineralogy and climate together.
Boundary: where this process starts
Starts with: Weathering forms short-range-order Fe and Al minerals
Boundary: where it ends
Ends after: Carbon stock is set jointly by geochemistry and climate
Line thickness = size of impact (1 to 5)% on a line = chance a fork takes that branch📄 = pieces of evidence on a stepNegative effectLoops backHypothesisResource used up (arrow into the step)Resource used, not used upResource made or released (arrow out of the step)
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- Loop
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- Size of impact
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Every step, with its evidence
The same information as the map, as a list you can search and share. Click a participant or resource to see everywhere it appears.
Weathering forms short-range-order Fe and Al minerals
Evidence (1) · added by Skeptic
- Torn et al. 1997, doi:10.1038/38260: Short-range-order minerals form from weathering of volcanic material and vary with age and rainfall. (confidence 0.8)
Organic matter sorbs to reactive minerals and turns over more slowly
Evidence (1) · added by Skeptic
- Torn et al. 1997, doi:10.1038/38260: Radiocarbon turnover times lengthened with mineral-associated carbon. (confidence 0.8)
Carbon stock is set jointly by geochemistry and climate
Evidence (1) · added by Skeptic
- Doetterl et al. 2015, Soil carbon storage controlled by interactions between geochemistry and climate, Nature Geoscience, doi:10.1038/ngeo2516: Soil geochemistry together with climate predicted soil carbon storage across sites. (confidence 0.8)