摘要：

The trace-element geochemistry of the Black Sea is dominated by the strong pycnocline separating the oxygenated and reducing environments. Using values of the vertical advective velocity and vertical eddy-diffusion coefficient derived from a model, the flux of dissolved sulfide, manganese, iron, copper, and zinc through this interface was estimated. The calculated sulfide flux of 145 mM/m/sup 2//year is smaller than estimates of sulfide production in the sediments by a factor of four, but is consistent with estimates of chemosynthesis, suggesting that a sulfide-removal mechanism not explained by the model must operate. From the manganese data, deductions were made that about 78 percent of the detrital load of rivers entering the Black Sea is deposited near the mouth of the river and only 22 percent is spread over the surface of the Black Sea. If the mean sinking rate is 1,000 m/year, the data on the distribution and elemental composition of particulate matter in the Black Sea are in agreement with estimates of river input. (auth)

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