Ecosystems global warming

ABSTRACT The locations, magnitudes, variations and mechanisms responsible for the atmospheric C02 sink are uncertain and under debate. Previous studies concentrated mainly on oceans, and soil and terrestrial vegetation as sinks. Here, we show that there is an important C02 sink in carbonate dissolution, the global water cycle and photosynthetic uptake of DIC by aquatic ecosystems. The sink constitutes up to 0.82 Pg C/a 0.24 Pg C/a is delivered to oceans via rivers and 0.22 Pg C/a by meteoric precipitation, 0.12 Pg C/a is returned to the atmosphere, and 0.23 Pg C/a is stored in the continental aquatic ecosystem. The net sink could be as much as 0.70 Pg C/a, may increase with intensification of the global water cycle, increase in C02 and carbonate dust in atmosphere, reforestation/afforestation, and with fertilization of aquatic ecosystems. Under the projection of global warming for the year 2100, it is estimated that this C02 sink may increase by 22%, or about 0.18 Pg c/a. 

This sink, a negative climate feedback mechanism, may increase with the global-warming-intensified GWC, the increase in C02 and carbonate dust in atmosphere, reforestation/afforestation, and fertilization of the aquatic ecosystems. Using the global warming projection for the year 2100 by IPCC, it is estimated that the C02 sink by the GWC will increase by 22%, or 0.18 Pg c/a. 

Biotic resources Global warming Physical ecosystem... 

CO2, generated by the activity of man, results in an increase in the partial pressure of CO2, a decrease in pH, and a decrease in HCOj concentration. This could change ocean chemistry to reduce the bioavailability of iron, increasing Fe stress of phytoplankton populations in some parts of the ocean. Whether massive iron fertilization of the oceans could absorb this buildup of CO2, which is associated with global warming according to many people, is still highly controversial, in view of the unknown potential effects on marine ecosystems. 

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