Black Sea Oceanography Proceedings of the NATO Advanced Research Workshop on Black Sea Oceanography Çeşme-lzmir, Turkey, October 23-27, 1989

Proceedings of the NATO Advanced Research Workshop, Çesme, Izmir, Turkey, October 23-27, 1989 Front Matter....Pages i-xv Hydrographic Variability in the Black Sea....Pages 1-16 Double Diffusive Intrusions, Mixing and Deep Sea Convection Processes in the Black Sea....Pages 17-42 On the Dynamics of the Southern Black Sea....Pages 43-63 Noble Gases and Tritium in the Black Sea....Pages 65-74 Factors Affecting the Oxygen Isotopic Composition of the Black Sea....Pages 75-88 Geochemical and Structural Aspects of the Pycnocline in the Black Sea (R/V KNORR 134-8 LEG 1, 1988)....Pages 89-110 Nitrogen Transformations in the Oxic Layer of Permanent Anoxic Basins: The Black Sea and the Cariaco Trench....Pages 111-124 Thermodynamic Modeling of Trace Metal Speciation in the Black Sea....Pages 125-160 Total and Suspended Cadmium, Cobalt, Copper, Iron, Lead, Manganese, Nickel, and Zinc in the Water Column of the Black Sea....Pages 161-172 Potential for Manganese(II) Oxidation and Manganese(IV) Reduction to Co-Occur in the Suboxic Zone of the Black Sea....Pages 173-185 Sulfur and Iodine Speciation in the Water Column of the Black Sea....Pages 187-204 The Oxidation of H 2 S with O 2 in the Black Sea....Pages 205-227 Ruthenium-106 in the Black Sea....Pages 229-243 137 Cs and 239,240 Pu Concentrations in the Black Sea Water Column....Pages 245-255 Radionuclide Distributions in Recent Black Sea Sediments....Pages 257-270 Microbial Processes in the Black Sea Water Column and Top Sediment: An Overview....Pages 271-286 A Review of the General Food Web in the Black Sea....Pages 287-292 Biogenic Aggregate Sedimentation in the Black Sea Basin....Pages 293-306 On the Sulfur and Carbon Balances in the Black Sea....Pages 307-318 Organic Matter Sources in the Black Sea as Inferred from Hydrocarbon Distributions....Pages 319-341 Organic carbon and nitrogen geochemistry of Black Sea surface sediments from stations spanning the oxic:anoxic boundary....Pages 343-359 The Nature and Distribution of Fluorescent Dissolved Organic Matter in the Black Sea and the Cariaco Trench....Pages 361-378 Recent Geological Evolution of the Black Sea: An Overview....Pages 379-387 The Effects of Neotectonic Movements on the Recent Sedimentation of the SW Black Sea....Pages 389-400 Upper Holocene Sediments of the Black Sea: Summary of Leg 4 Box Cores (1988 Black Sea Oceanographic Expedition)....Pages 401-441 Uranium Precipitation in Black Sea Sediments....Pages 443-458 Pollution Chronology of the Golden Horn Sediments....Pages 459-468 Sampling and Analysis of Aerosols in the Black Sea Atmosphere....Pages 469-487 Anoxic basins are ofgreat interest to oceanographersofall disciplines. Theirextreme conditionsresult from acombinationofhigh oxygen utilization and restricted circulation. It is necessery to understand present -day anoxic environments ifwe are to understand the early evolution of the oceans (e.g. SiIlen, 1965). Sarmiento et al.(1988a) explored the causes of anoxia in the global ocean, which is in effect a "closed" basin and in marginal seas such as the Eastern Mediterranean (Sarmiento et al. 1988b). Anoxic conditions have been proposed toexist in various ocean basins at different times in the geological past (e.g. the Crataceous period; Weissert, 1981) and possibly as recent as the last glacial maximum (e.g., Sarmiento and Toggweiler,1984). The modern Black Sea has been considered as the type anoxic basin. It is the world's 2 3 largest permanaently anoxic basin (area = 423,000 km ; volume = 534,000 km) and is thought to be aquasi-steady state system. It is extremely isolated from the rest ofthe world's oceans. Only the narrow and shallow Bosporus Strait provides water exchange with the Mediterranean. Concentrationsofhydrogen sulfide reach valuesof350 Mm in the deep water and the oxygen-hydrogen sulfide Interface exists between 80 and 200m waterdepth. The hydrographic regime is characterized by low salinity surface water of riverine origin overlying high salinity deep waterofMediterranean origin. Asteep pycnocline is the primary phycical barrier to mixing and is the origin of the stability of the anoxic interface Proceedings of the NATO Advanced Research Workshop, Cesme, Izmir, Turkey, October 23-27, 1989