On the basis of analytical chemical data for numerous rain, river, lake, and ocean samples, the three major mechanisms controlling world surface water chemistry can be defined as atmospheric precipitation, rock dominance, and the evaporation-crystallization process.

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Trace metals transported by the Amazon (and Yukon rivers were analytically partitioned among the transport phases: in solutions, ion exchange, organic materials, metallic coatings, and crystalline solids. The distribution for both rivers is similarly proportioned, with copper and chromium transported mainly in the crystalline solids, manganese in coatings, and iron, nickel, and cobalt distributed equally between precipitated metallic coatings and crystalline solids.

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The size and settling velocity of flocs of suspended sediments from the Chesapeake Bay were measured in laboratory experiments and in the field. The curves between floc diameter and settling velocity showed a non‐Stoke's relationship that was best described by the following: settling velocity (cm/s) = 1.73 (floc diameter, cm)0.78. Furthermore, the relationship between floc diameter and settling velocity indicated that the floe density decreased as the floes increased in size. In addition to changing density, a cylinder shape was found to be the best shape factor.

rn Coagulation experiments with four natural samples and the same samples with the organic coatings removed were conducted in Couette-and blade-type reactors. These experiments showed that the natural coated samples coagulated significantly slower than the samples with the coatings removed, Dissolved organic material did not have a significant effect relative to the particle organic coatings.

Analytical results of sampling during both wet and dry seasons along the Amazon River, at its mouth, and from 16 tributaries reveal that the physical weathering dominant in the Andean mountainous environment controls both the overall composition of the suspended solids discharged by the Amazon and the amount of dissolved salts and suspended solids discharged.