Influencia en la regeneración bentónica en el ciclo biogeoquímico del CO2 en sistemas litorales

Resum

The benthic fluxes of inorganic carbon were measured in the Bay of Cádiz, located in the SW of the Iberian Peninsula (Southern Europe). The values measured ranged between 74 and 224 mmol m –2 d –1 , which are higher than most reported fluxes. They were linearly correlated with the organic carbon content in surface sediments. For the Bay of Cádiz, a carbon budget is proposed. It was determined that 53% of the benthic inorganic carbon production is used by the phytoplankton of the area, and 43% is exported by tides to other littoral areas. The rest of the benthic production, together with direct emission of CO2 from intertidal sediments to the atmosphere, yielded a maximum net flux of 5.6 · 10 8 mol C y –1 . If extrapolated to coastal areas globally, these values are particularly significant. Taking 44 mmol m –2 d –1 as an average value for benthic fluxes of dissolved inorganic carbon, it is estimated that the benthic CO 2 production by coastal ecosystems is about 4.2 · 10 14 mol y –1 , similar to the estimated annual CO 2 emissions to the atmosphere from the burning of fossil fuels.