Photosynthesis: Ecology

Giles Johnson, University of Manchester, Manchester, UK

Published online: January 2006

DOI: 10.1038/npg.els.0003198

While most plants depend directly on photosynthesis for energy, their ability to capture light energy and grow will be affected by many other environmental factors, including water supply, nutrients and temperature. Various adaptations of photosynthesis exist that allow plants to tolerate extreme environmental conditions. Ultimately, the overall net photosynthetic rate of ecosystems has a major impact on the global carbon budget.

Keywords: adaptation; C3; C4; CAM; sun-shade; transpiration

Figure 1. Summary of the different photosynthetic pathways. C3 plants fix  CO2 directly, using the enzyme ribulose bisphosphate carboxylase oxygenase (Rubisco), reaction  CO2 with ribulose bisphosphate (RuBP) to form phosphoglyceric acid (PGA) in the chloroplasts of the mesophyll. C4 plants, react PEP carboxylase to react  CO2 with phosphoenolpyruvate (PEP) to form oxaloacetic acid (OAA) which is in turn converted to malate. This is transferred to the bundle sheath, where malate is broken down to release  CO2, which is used by Rubisco. CAM plants use PEP carboxylase to fix  CO2 at night and then break down the malate so produced during the day to provide  CO2 for Rubisco.
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 Further Reading
    book Crawford RMM (1989) Studies in Plant Survival. Oxford: Blackwell's Scientific Publications.
    book Fitter AH and Hay RKM (1987) Environmental Physiology of Plants. London: Academic Press.
    book Larcher W (1995) Physiological Plant Ecology. Berlin: Springer.
    book Lambers H, Chapin FS and Pons TL (1998) Plant Physiological Ecology. Berlin: Springer.
    book Lüttge U (1997) Physiological Ecology of Tropical Plants. Berlin: Springer.

Related Sub-Topics:

Physiological Ecology | Biogeochemical Cycles | Plant Ecology | Photosynthesis
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Article Title: Photosynthesis: Ecology
 
How to Cite close
Johnson, Giles(Jan 2006) Photosynthesis: Ecology. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0003198]