The carbon cycle in the marine environment is especially complex. In particular, the carbon contained in the organic and inorganic particulate reaching the sea bottom is involved in complicated biogeochemical processes. These can lead to a production of dissolved organic (DOC) and inorganic (DIC) carbon, both at the sediment-water interface and in the pore waters of the early centimeters of the sediment itself. This dissolved carbon production gives rice to dissolved carbon releases at the sedimentwater interface. Under different conditions, the biogeochemical processes near the sediment-water interface, known as early diagenesis processes, can also lead to a carbon precipitation with consequent absorption by the sediment. The early diagenesis processes can therefore generate benthic fluxes of dissolved carbon both out of the sediment or inside the sediment. Furthermore, other than the dissolved benthic carbon fluxes of early diagenesis origin, there may be also the dissolved carbon releases of volcanic and hydrothermal origin or due to deeper diagenetic processes (CO2, C1-C6). In order to understand and quantify the carbon cycle in the marine environment it is therefore essential to measure the dissolved carbon benthic fluxes and their isotopic composition, occurring at the sedimentwater interface and the processes of early diagenesis or volcanic or deep diagenesis that generated them. The dissolved fluxes at the sediment-water interface are measured by the use of benthic chambers and landers while the early diagenesis processes are investigated by the sediment core extrusion in inert atmosphere and the analysis and study of the pore water chemical composition. The dissolved benthic fluxes generated by the early diagenesis processes, when the benthic chamber are not available, can also be quantified by core incubation or by pore water modeling. Over the years, several CNR groups measured the dissolved benthic fluxes and studied the early diagenesis processes in the Adriatic and the Ionian seas. This led to the determination of the benthic flows of dissolved carbon in most of the Adriatic sea floor and in some areas of the Ionian Sea. Furthermore, to measure the in situ dissolved benthic fluxes, the CNR realized an automatic benthic chamber and a lander able to operate up to full ocean depths (6000 m depth): The Lander Amerigo and the CBA.
Marine dissolved Carbon fluxes at sediment-water interface and early diagenesis processes.
Spagnoli F;Patrizia Giordano;
2018
Abstract
The carbon cycle in the marine environment is especially complex. In particular, the carbon contained in the organic and inorganic particulate reaching the sea bottom is involved in complicated biogeochemical processes. These can lead to a production of dissolved organic (DOC) and inorganic (DIC) carbon, both at the sediment-water interface and in the pore waters of the early centimeters of the sediment itself. This dissolved carbon production gives rice to dissolved carbon releases at the sedimentwater interface. Under different conditions, the biogeochemical processes near the sediment-water interface, known as early diagenesis processes, can also lead to a carbon precipitation with consequent absorption by the sediment. The early diagenesis processes can therefore generate benthic fluxes of dissolved carbon both out of the sediment or inside the sediment. Furthermore, other than the dissolved benthic carbon fluxes of early diagenesis origin, there may be also the dissolved carbon releases of volcanic and hydrothermal origin or due to deeper diagenetic processes (CO2, C1-C6). In order to understand and quantify the carbon cycle in the marine environment it is therefore essential to measure the dissolved carbon benthic fluxes and their isotopic composition, occurring at the sedimentwater interface and the processes of early diagenesis or volcanic or deep diagenesis that generated them. The dissolved fluxes at the sediment-water interface are measured by the use of benthic chambers and landers while the early diagenesis processes are investigated by the sediment core extrusion in inert atmosphere and the analysis and study of the pore water chemical composition. The dissolved benthic fluxes generated by the early diagenesis processes, when the benthic chamber are not available, can also be quantified by core incubation or by pore water modeling. Over the years, several CNR groups measured the dissolved benthic fluxes and studied the early diagenesis processes in the Adriatic and the Ionian seas. This led to the determination of the benthic flows of dissolved carbon in most of the Adriatic sea floor and in some areas of the Ionian Sea. Furthermore, to measure the in situ dissolved benthic fluxes, the CNR realized an automatic benthic chamber and a lander able to operate up to full ocean depths (6000 m depth): The Lander Amerigo and the CBA.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
