Marine algal nutrient regeneration: the enrichment of the water surrounding A{tilde}no Nuevo Island, California by pinnipeds

The chemical composition of sea water has been described as being relatively constant with respect to the ratios of the major components (Dittmar, 1884). There are, however, certain of the minor constituents of sea water which are less conservative and may vary substantially with time and location. There are a number of physical factors related to water movement which affect the concentrations of minor constituents, but major fluctuations ultimately result from biological processes (Harvey, 1966). Two of the minor sea water constituents which display large variations in concentrations are the compounds of nitrogen and phosphorus. Since these compounds are also major plant nutrients, their concentrations in sea water can indicate the degree of fertility of the water. Brandt (1899) was among the first to suggest that, with reference to "Liebig's Law of the Minimum," the growth of marine algae in the euphotic zone is often limited by the availability of nutrients, especially nitrogen and phosphorus. Brandt's suggestion has since been well substantiated by Harvey (1928, 1940), Cooper (1933). Chu (1949), and others.