How does rising atmospheric CO2 affect marine organisms?

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Growth Response to CO2 (Sugars) -- Summary
Plants grown in CO2-enriched atmospheres nearly always exhibit increased photosynthetic rates, which typically lead to increased foliar concentrations of total nonstructural carbohydrates, including various sugars.   Schortemeyer et al. (1999), for example, reported significant increases in leaf total nonstructural carbohydrate contents in an Australian tree species subjected to twice-ambient atmospheric CO2 concentrations for six weeks.  Similarly, Wurth et al. (1998) observed that twice-ambient CO2 levels increased leaf sugar concentrations by an average of 30% in four Panamanian tropical tree species.  Even a short eight-day expose of apple seedlings to an atmospheric CO2 concentration of 1600 ppm led to a 38% increase in leaf sorbitol concentrations.

Atmospheric CO2 enrichment has also been documented to increase sugar contents in other plant organs in addition to leaves.   Lake and Hughes (1999), for example, found a doubling of the air's CO2 concentration to produce a 2.4-fold increase in nectar production in nasturtium flowers.  Thus, it would appear that elevated CO2 has the potential to increase the sugar contents of many plant organs, where it can be used to produce energy and raw carbon-based materials for many different purposes.

Lake, J.C. and Hughes, L.   1999.   Nectar production and floral characteristics of Tropaeolum majus L. grown in ambient and elevated carbon dioxide.   Annals of Botany 84: 535-541

Pan, Q., Wang, Z. and Quebedeaux, B.   1998.   Responses of the apple plant to CO2 enrichment: changes in photosynthesis, sorbitol, other soluble sugars, and starch.  Australian Journal of Plant Physiology 25: 293-297.

Schortemeyer, M., Atkin, O.K., McFarlane, N. and Evans, J.R.   1999.  The impact of elevated atmospheric CO2 and nitrate supply on growth, biomass allocation, nitrogen partitioning and N2 fixation of Acacia melanoxylon.   Australian Journal of Plant Physiology 26: 737-774.

Wurth, M.K.R., Winter, K. and Korner, C.   1998.   Leaf carbohydrate responses to CO2 enrichment at the top of a tropical forest.  Oecologia 116: 18-25.