amount of substance of that element (in mol or mass units),
species
The element that is given ("C", "H", "O", "N", "P"),
method
measurement unit ("mol" or "mass"),
ratio
average elemental composition.
Details
The average elemental composition of marine plankton (Redfield ratio)
is traditionally assumed to be
C106 H263 O110 N16 P1
(Redfield 1934, 1963, Richards 1965). Note that while the C:N:P ratio
is widely agreed there is still discussion about the average of O and
H, e.g. C106 H180 O45 N16 P1
(Stumm, 1964).
Note also that there are, of course, large differences depending on
species and physiological state.
Value
A data frame with the estimated ratio of the main elements.
References
Redfield AC, 1934. On the proportions of organic derivations in sea
water and their relation to the composition of plankton. In: James
Johnstone Memorial Volume. (ed. R.J. Daniel). University Press of
Liverpool, 177-192.
Redfield, AC, Ketchum, BH and Richards FA, 1963. The influence of
organisms on the composition of seawater. In: Hill, MN, Editor, The
Sea vol. 2, Interscience, New York (1963), pp.26-77.
Richards FA, 1965. Anoxic basins and fjords. In: Riley JP, Skirrow
D. (Eds.), Chemical Oceanography, vol. 1. Academic Press, New York,
611-645. (cited in Hedges et al, 2002).
Stumm W, 1964. Discussion (Methods for the removal of phosphorus and
nitrogen from sewage plant effluents by G. A. Rohlich). In
Eckenfelder, WW (ed.), Advances in water pollution research. Proc. 1st
Int. Conf. London 1962, volume 2, pp. 216-229. Pergamon.
Vollenweider RA, 1985. Elemental and biochemical composition of
plankton biomass: some comments and explorations. Arch.
Hydrobiol. 105, 11-29.
Anderson LA, 1995. On the hydrogen and oxygen content of marine
plankton. Deep-Sea Res. 42, 1675-1680.
Hedges JI., Baldock JA, Gelinas Y, Lee C, Peterson ML and
Wakeham SG, 2002. The biochemical and elemental compositions of
marine plankton: A NMR perspective. Marine Chemistry 78, 47-63.
See Also
AtomicWeight, molvol, molweight
Examples
## Redfield ratio
redfield(1, "P")
## returns the molar Redfield ratio, rescaled to nitrogen
redfield(1, "N")
## how many mass units are related to 2 mass units (e.g. mg) P
redfield(2, "P", "mass")
redfield(c(1, 2, 3), "N", "mass")
## mass percentage of elements
x <- redfield(1, "P", "mass")
x / sum(x)
## with alternative elemental composition (Stumm, 1964)
x <- redfield(1, "P", "mass",
ratio = c(C = 106, H = 180, O = 45, N = 16, P = 1))
x / sum(x)
## rule of thumb for fresh mass (in mg) formed by 1 microgram P
redfield(1, "P", "mass")$C * 2 * 10 / 1000
sum(redfield(1, "P", "mass",
ratio = c(C = 106, H = 180, O = 45, N = 16, P = 1))) * 10 / 1000