Phytoplankton pigments, effect

Bianchi, T.S., Johansson, B., and Elmgren, R. (2000a) Breakdown pf phytoplankton pigments in Baltic sediments effects of anoxia and loss of deposit-feeding macrofauna. J. Exp. Mar. Biol. Ecol. 251, 161-183. 

RP-HPLC has also been applied for the study of the effect of salinity on the diversity of prokaryotic and eukariotic phytoplankton. Seawater samples were fdtered and the filters were sonificated with acetone and left for 24 h at 4°C. Separation was performed in an ODS column (250 X 4.6 mm i.d. particle size 5 pm). The concentrations of pigments are compiled in Table 2.100. 

Vince, S., and Valiela, I. (1973) The effects of ammonium and phosphate enrichments on chlorophyll a pigment ratios and species composition of phytoplankton of Vineyard Sound. Mar. Biol. 19, 69-73. 

Dohler, G., and Hagmeier, E. (1997). UV efFects on pigments and assimilation oF N-ammonium and N-nitrate by natural marine phytoplankton oF the North Sea. Botanica Acta 110, 481—488. 

Table 1 is the compilation of pigment data obtained from analyses of the sediment trap samples. The data reveal, from the increase in the relative amounts of pheophytin-a and pheophor-bide-a, a large degree of Mg and Mg plus phytol loss, respectively. The deeper sample, upon microscopic examination, was found to contain a majority of broken, relative to intact, phytoplankton cells (diatom dominated) occurring mainly in fecal pellets. Thus, the change in the distribution of tetrapyrrole pigments, occurring with depth in the water column, reveals the combined effects of senescence/death and predation. The latter is evidenced by the increase in pheophorbide-a relative to pheophytin-a (37,40). 

More field measurements of UV absorption by phytoplankton are needed and these should be scaled to chlorophyll concentration and evaluated for spatial and temporal patterns across gradients (trophic, UV, nutrient, grazing). The effect of depth and mixing should be evaluated for effects on U V exposure and on the response of cells to adjust UV-absorbing and photosynthetic pigments. 

J.I. Goes, N. Handa, S. Taguchi, T. Hama (1994). Effect of UV-B radiation on the fatty-acid composition of the marine-phytoplankton Tetraselmis sp - relationship to cellular pigments. Mar. Ecol. Prog. Ser., 114,259-274. 

G. Dohler (1995). Effects of UV-A and UV-B radiation on pigments and assimilation of 15N-ammonium and 15N-nitrate by natural phytoplankton of the Wadden Sea. Beitr. Biol. Pflan., 69,1-16. 

Hoepflher N, Sathyendranath S Effect of pigment composition on absorption properties of phytoplankton. Mar Ecol Prog Ser 73(l) ll-23, 1991. 

Limitation of nitrogen causes a decline in the level of chlorophyll in algal cells, because N is a major constituent of the chlorophyll molecule. Under these conditions there is often a concomitant increase in carotenoids such as P-carotene within cells. Biologists studying the effect of nutrient limitation on aquatic ecosystems would like to measure the levels of these pigments in single cells so that the variability of response within phytoplankton populations to nutrient change can be accessed. Raman spectroscopy offers this potential, and... 

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