Obiettivo WHERE A RADIONUCLIDE IS PRESENT ON THE SEA-BED, THE PROCESSES OCCURING IN THE UPPERMOST SEDIMENTARY LAYER AND THE LOWEST WATER LAYERS (THE BENTHIC BOUNDARY LAYER - BBL) ARE OF GREAT IMPORTANCE FOR THE TRANSPORT OF RADIONUCLIDES TO MAN. THESE PROCESSES MUST BE EXAMINED IN GREATER DETAIL IN ORDER TO ARRIVE AT A DESCRIPTION OF THE PHYSICAL AND BIOLOGICAL PATHWAYS OF TRANSFER OF RADIONUCLIDES. THE AIM OF THIS RESEARCH IS TO DESCRIBE THE DISPERSION OF RADIOACTIVE SUBSTANCES IN AND IMMEDIATELY ABOVE THE SEDIMENT AND TO DETERMINE THE EXTENT TO WHICH RADIONUCLIDES CAN BE TRANSPORTED FROM THE OCEAN BED TO MAN. THE MAIN THEMES OF THIS GEOCHEMICAL AND BIOLOGICAL RESEARCH ARE THE INTERACTION BETZWEEN SEDIMENTS AND THE RADIONUCLIDES RELEASED FROM WASTE, AND THE ROLE PLAYED BY INFAUNA AND SEA-BED FAUNA IN THE TRANSPORT OF RADIONUCLIDES TO MAN. GEOCHEMICAL AND BIOLOGICAL RESEARCH ARE CLOSELY RELATED OWING TO THE USE OF THE SAME SAMPLING TECHNIQUE (BOX CORES) FOR BOTH SEA-BED SEDIMENT AND INFAUNA. MOREOVER, THE SAME CHEMICAL AND RADIO-CHEMICAL METHODS ARE EMPLOYED TO ANALYSE THE SAMPLES OBTAINED. GEOCHEMICAL AND BIOLOGICAL RESEARCH WILL THEREFORE BE DEALT WITH TOGETHER. DETERMINATIONS WILL BE MADE OF THE GRAIN-SIZE DISTRIBUTION, THE CONTENT OF ORGANIC CARBON, CALCIUM AND SILICATE IN THE CONSTITUENT, THE CLAY-MINERALOGY AND THE MAIN- AND TRACE-ELEMENTS OF THE SEDIMENT. THESE SEDIMENT PROPERTIES WILL BE DETERMINED FROM SAMPLES OBTAINED WITH THE AID OF BOX CORERS AND PISTON CORERS. THE MOBILITY OF ELEMENTS DEPENDS ON THEIR DISTRIBUTION BETWEEN SEDIMENT AND PORE WATER. THESE EQUILIBRIA WILL BE STUDIED BY DETERMINING THE CONTENT OF STABLE ISOTOPES OR CHEMICAL ANALOGUES OF WASTE-BOUND RADIONUCLIDES IN SEDIMENT AND PORE WATER. THE REDOX SYSTEM IN THE CORE WILL BE DETERMINED BY MEASURING THE O2, FE, MN, SO4 AND N CONSTITUENTS OF THE PORE WATER. RATES OF SEDIMENT ACCUMULATION IN THE AEREA WILL BE DETERMINED WITH THE HELP OF THE NATURAL RADIONUCLIDES C-14 AND TN-230. OTHER RADIONUCLIDES LIKE PB-210, AND X-RAY PHOTOGRAPHY WILL BE USED TO GAIN AN UNDERSTANDING OT THE BIOTURBATION PROCESS. THE RESEARCH PROGRAM COVERS THE COLLECTION OF DEEP-SEA ORGANISMS WITH TRAWLS AND BOX CORES AND THEIR IDENTIFICATION AND CHEMICAL ANALYSIS. DATA CONCERNING THE ACCUMULATION IN THESE ORGANISMS OF RADIONUCLIDES FROM WASTE (THE FIRST STAGE IN A POSSIBLE FOOD CHAIN) CAN BE OBTAINED BY THE CHEMICAL ANALYSIS OF ELEMENTS WHICH ARE PRESENT AS RADIOACTIVE ISOTOPES IN DUMPED WASTE AND OF ELEMENTS WHICH CAN BE CONSIDERED CHEMICALLY ANALOGOUS TO CONSTITUENTS OF RADIOACTIVE WASTE. COMPARISON OF THE CHEMICAL ANALYSES OF THE ORGANISMS AND OF THE SEA-BED SEDIMENT AND PORE WATER IS OF PARTICULAR IMPORTANCE, SINCE THE SEDIMENT-BOUND RADIONUCLIDES ARE LIKELY TO ATTAIN THE HIGHEST CONCENTRATIONS IN THE ORGANISMS. A COMPARISON WITH THE MUCH GREATER VOLUME OF CORRESPONDING DATA RELATING TO SHALLOW WATER WILL INDICATE TO WHAT EXTENT THE LATTER ARE APPLICABLE TO DEEP-SEA CONDITIONS. Campo scientifico engineering and technologyother engineering and technologiesnuclear engineeringnuclear waste managementnatural scienceschemical sciencesinorganic chemistryalkaline earth metalsnatural scienceschemical sciencesnuclear chemistryradiation chemistry Programma(i) FP1-RADPROT 6C - Multiannual research and training programme (Euratom) in the field of radiation protection, 1985-1989 Argomento(i) Data not available Invito a presentare proposte Data not available Meccanismo di finanziamento Data not available Coordinatore NEDERLANDS INSTITUUT VOOR ONDERZOEK DER ZEE Contributo UE Nessun dato Indirizzo PROJ.DORA P.O. BOX 59 1790 AB DEN BURG Paesi Bassi Mostra sulla mappa Costo totale Nessun dato
