Resumo

MERCADO, Jesús M. Ecofisiología y bomba biológica en el océano. INCI [online]. 2002, vol.27, n.10, pp.537-543. ISSN 0378-1844.

Some authors have suggested that the marine plants could act as a sink of atmospheric CO2 by increasing their photosynthetic rates (oceanic biological pump). Most of the research oriented to test this hypothesis has focused on the estimation of CO2 fluxes between atmosphere and ocean. In contrast, relatively little effort has been made to determine in the laboratory the response of marine plants to CO2 enrichment. Nevertheless, some conclusions can be drawn from the analysis of available experimental results: 1) About 30% of the species of algae would respond to a CO2 enriched environment by increasing their photosynthetic rates, provided they are not saturated by the actual CO2 concentration in seawater. However, this positive effect could be low in terms of growth. 2) In most species the increase in photosynthesis rates could be expected only if CO2 enrichment would be accompanied by the availability of other resources necessary for growth, such as irradiance and nutrients. 3) Interspecific relationships among species of algae and other organisms could decrease the efficiency of the oceanic biological pump.

Palavras-chave : Bomba Biológica ; CO2 ; Fitoplancton ; Fotosíntesis ; Océano .