Earth-science reviews, 1997-03, Vol.42 (1-2), p.95-117
1997
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Details
- Autor(en) / Beteiligte
- Titel
- Calcification generates protons for nutrient and bicarbonate uptake
- Ist Teil von
- Earth-science reviews, 1997-03, Vol.42 (1-2), p.95-117
- Ort / Verlag
- Amsterdam: Elsevier B.V
- Erscheinungsjahr
- 1997
- Quelle
- Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)
- Beschreibungen/Notizen
- The biosphere's great carbonate deposits, from caliche soils to deep-sea carbonate oozes, precipitate largely as by-products of autotrophic nutrient acquisition physiologies. Protons constitute the critical link: Calcification generates protons, which plants and photosynthetic symbioses use to assimilate bicarbonate and nutrients. A calcium ATPase-based “trans” mechanism underlies most biological calcification. This permits high calcium carbonate supersaturations and rapid carbonate precipitation. The competitive advantages of calcification become especially apparent in light and nutrient-deficient alkaline environments. Calcareous plants often dominate the lower euphotic zone in both the benthos and the plankton. Geographically and seasonally, massive calcification concentrates in nutrient-deficient environments including alkaline soils, coral reefs, cyanobacterial mats and coccolithophorid blooms. Structural and defensive uses for calcareous skeletons are sometimes overrated.