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Author Egleston, Eric Stefan
Title Biological, chemical, and policy aspects of the relationship between productivity and the ocean carbon cycle
book jacket
Descript 159 p
Note Source: Dissertation Abstracts International, Volume: 68-12, Section: B, page: 8298
Thesis (Ph.D.)--Princeton University, 2008
The redistribution of CO2 between the oceans and the atmosphere is a function of biological, chemical, and physical processes. This thesis addresses components of the biological and chemical processes that regulate the flux of CO2 across the atmosphere-ocean boundary. In addition, it addresses some public policy components of emerging technologies that aim to intentionally manipulate this flux
Productivity in the ocean is primarily limited by the macronutrients nitrogen and phosphorus, however the assimilation of these nutrients can be limited by the availability of trace metals. The assimilation of urea, an environmentally important source of nitrogen, is facilitated by urease, a Ni-containing metalloenzyme. The diatoms Thalassiosira weissflogii and Thlassiosira pseudonana become limited at low Ni concentrations, when growing on urea. When grown at low Ni, T. weissflogii cells utilizing urea as a source of nitrogen hyperaccumulate Zn through the upregulated Ni transport system and exhibit extreme sensitivity to Zn toxicity. The sensitivity of Ni-limited cells to Zn toxicity may be due to Zn interference with the insertion of Ni at the active site of urea. Such cascading interactions among trace metals resulting from limitation by one is likely a generalizable mechanism of metal toxicity. This may limit the use of urea as a source of nitrogen for primary production
The carbonate chemistry of the ocean buffers the chemical response to increasing oceanic dissolved inorganic carbon. We derive explicit expressions of several buffer factors of interest for ocean chemistry, including the Revelle factor. We then use the buffer factors in simplified simulations of the ocean response to increasing atmospheric CO2 to analyze the sensitivity of the CO2 concentration, the pH, and the CaCO3 saturation to various biological and physical oceanic processes. The factors that we derive are useful tools for understanding how potential feedbacks on CO 2 accumulation in the atmosphere and oceans will alter ocean chemistry
The intentional manipulation of pelagic production to enhance the biological uptake of CO2 by fertilizing the oceans with iron will have implications on ocean productivity and carbonate chemistry in the ocean. The efficacy and ecological ramifications of fertilization remain highly uncertain. As currently structured, carbon markets encourage the premature implementation of this technology; regulation is needed to structure markets in such a way as to avoid rewarding environmentally destructive or risky behavior
School code: 0181
DDC
Host Item Dissertation Abstracts International 68-12B
Subject Biology, Oceanography
Engineering, Environmental
0416
0775
Alt Author Princeton University
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