INTRODUCTXON i>*trrtnfR iwim .rti .«• «ojl3 *V3l (rC.Tmfc iinuwwly cnwn«1 iims MASTER I met a traveller from an antique land Who said: "Two vast and trunkless legs of stone Stand in the desert. Near them, on the sand. Half sunk, a shattered visage lies, whose frown, And wrinkled lip, and sneer of cold command. Tell that its sculptor well those passions read Which ye« survive, stamped on these lifeless things. The hand that mocked them and the heart that fed; And on the pedestal these works appear; 'My name is Ozyaandias, King of Kings; Look on sty works, ye Mighty, and despair!' Nothing beside remains, Round the decay Of that colossal wreck, boundless and bare The lone and level sands stretch far away." (P.B. Shelley, 1817) Phytoplankton growth processes are reasonably well-known functions of light, temperature, and nutrients; however, their loss processes are comparatively unknown. For example, the low productivity and nitrate content of most oceanic surface waters (Fig. 1) reflect: the slow upward rate of nutrient input across the main thexmocline to the euphotic zone. At the coastal boundaries of the ocean, e.g., on the continental shelves, daily fluxes of nitrate supply and ensuing productivity are 1 to 2 orders of magnitude larger (Walsh, 1976) as a result of locally intensified physical processes of upwelling, river runoif, and tidal nixing. 1S N estimates of nitrate uptake by phytoplankton suggest that only 10% of the daily nitrogen demand of photosynthesis is met by nitrate in the open ocean (Eppley and Peter sen, 1979), whereas "nitrate is "x.50% of the daily nitrogen source for phytoplankton in coastal waters off Peru (Maclsaac and Dugdale, 1972), New York (Conway and Whitledge, 1973), California (R. Eppley, personal coaninication), and Alaska {J. Goering, personal communication). Nitrate uptake is considered an estimate of the "new" daily production (Dugdale and Goering, 1967) that is available for export from an ecosystem and is associated with the OFtSS
