Diffusion limitation and the effect of cell size

The size range of phytoplankton, from single-celled picoplankton to chain or colony-forming microplankton, spans several orders of magnitude. A terrestrial analogue covering a similar size range would extend from mosses to trees. 0ver this size range, potential constraints on nutrient and inorganic carbon supply exerted by diffusive transport differ vastly. As indicated in equations (5.4) and (5.21), both the diffusive flux across the DBL and the relative contribution of chemical conversion...

The origin of the elements

The relative abundance of the elements in Earth's crust reveals a saw-toothed distribution of much more abundant light, even numbered elements, relative to rarer, 1 Ga giga annum (billions of years before present), Ma mega annum (millions of years), Ka (kilo annum) thousands of years. odd-numbered, heavier elements (Fig. 12.1). While the two lightest elements, H and He, were formed approximately 16 billion years ago in the 'Big Bang', all the heavier elements result from fusion of 2He nuclei or...

The Photosynthetic Carbon Reduction Calvin Cycle

Net photosynthetic carbon fixation involves a cycle of reactions named the photo-synthetic carbon reduction cycle, but also referred to as the Calvin or Calvin-Benson-Bassham cycle to honour its discoverers. Carbon enters the Calvin cycle as CO2 and leaves in the form of sugar phosphates (Fig. 3.2). The Calvin cycle requires energy in the form of ATP and reducing equivalents in the form of NADPH. It can be summarised as 1 6 C6H12O6 + H2O + 2 NADP+ + 3 ADP + 3 P (3.7) (Note equations (3.2) and...

Z2 Z1

Fs is now defined as an average utilisation over the depth of the water column and equation (4.I) becomes, after combining, rearranging, and evaluating the derivative (see Munk, 1966) AC - -2 e-Q(1 + P) (C2 - C1) +(-V) (4.III) Fig. 4.4 The average value of deep-ocean XCO2 (1-4 km depth) along the path of deep-water circulation (Gordon, 1986) from the North Atlantic to the North Pacific. The data are from GEOSECS (Takahashi et al., 1985). The line is the linear regression. Fig. 4.4 The average...

Implementing the Photo Acc model globally

As in the previous calculations (Plate 7.1), SeaWiFS measurements provided Csat and PAR fields. Pbopt was calculated as a function of Ig for the mixed layer. Monthly global fields of mixed layer depths were provided by the Fleet Numeric Meteorology and Oceanography Center (FNMOC) (7 Grace Hopper Avenue, Stop 1, Monterey, California, USA 93940). Ig at the bottom of the mixed layer was calculated from the monthly mean PAR data and mean attenuation coefficients derived from Csat following Morel...

The abiotic carbon cycle

Tectonic processes, driven by the internal heat of the planet, continuously sweep the oceans' sedimentary layers into the mantle of earth, to be later regurgitated by volcanic processes as igneous rocks. In so doing, carbon dioxide is outgassed to the 2 The rate of escape of H2 to space is critical. If planetary accretion is fast, and the planet cools rapidly, less H2 escapes and the resulting atmosphere of the planet reduces faster than if the planet cools slowly. atmosphere by vulcanoes and...