Shade and chromatic adaptation of phytoplankton photosynthesis in a thermally stratified sea

Takahashi, Masayuki; Ichimura, Shun‐ei; Kishino, Motoaki; Okami, Noboru

doi:10.1007/bf00391156

Cited by 22 publications

(11 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We consider the hypothesis that bottomup processes (nutrient and light availability) cause these observed gradients. We show that pigment concentrations and phytoplankton light absorption characteristics conform to vertical gradients in the spectral light field such that the phytoplankton were chromatically well adapted to the spectral quality of irradiance at their respective depths in the water column (Takahashi et al 1989;Bidigare et al 1990a;Lutz et al 2003). Further, we illustrate that phytoplankton cell sizes increased with depth on the nitrate gradient.…”

mentioning

confidence: 62%

Distribution and chromatic adaptation of phytoplankton within a shelf sea thermocline

Hickman

Holligan

Moore

et al. 2009

Limnology & Oceanography

View full text Add to dashboard Cite

Observations of vertical gradients in phytoplankton community structure were made through the water column of the seasonally stratified Celtic Sea, including within the thermocline. A deep chlorophyll maximum (DCM) was located within the thermocline at all stations, coupled to the nitracline. Vertical gradients in phytoplankton community composition were routinely observed within the thermocline. The cell abundance maxima for Synechococcus occurred in the upper part of the DCM coincident with a picoeukaryote abundance minima. Picoeukaryote abundance typically increased at or just above the peak of the DCM. Diatoms were observed occasionally at the DCM peak. Pigment compositions and phytoplankton absorption spectra indicated that the different phytoplankton communities were chromatically well adapted to the spectral composition of irradiance at the depths where they occurred in the water column. Profiles of vertical eddy diffusivity revealed that timescales for mixing between the phytoplankton layers within the thermocline were in excess of typical phytoplankton growth rates. The observed vertical gradients in community structure could therefore result from selection and niche partitioning of phytoplankton types on the light and nutrient gradient within the thermocline. The data further indicate that the pigments, light absorption characteristics, and cell size contribute to the phytoplankton selection process.The Celtic Sea, part of the temperate Northwest European shelf, is a tidally dynamic environment where water column structure is strongly influenced by the balance of solar heating and tidally generated mixing (Simpson and Hunter 1974). Much of the region becomes thermally stratified in April, initiating the spring phytoplankton bloom (Pingree et al. 1976). The water column remains stratified throughout the summer, with the thermocline forming a boundary between nutrient-depleted surface mixed layer (SML) above and the nutrient-rich bottom mixed layer (BML) below (Pingree et al. 1977). During this seasonal stratification, a deep chlorophyll maximum (DCM) is present within the thermocline (Pingree et al. 1977). The DCM is typically located toward the base of the density gradient, lies within the euphotic zone, and is strongly coupled to the nitracline (Holligan et al. 1984a,b;Sharples et al. 2001).Energy from tidally induced turbulence is dissipated at the base of the thermocline, causing upward mixing of nitrate into the thermocline from the BML and downward mixing of phytoplankton from the base of the DCM (Sharples et al. 2001). Previous observations in the Celtic Sea have revealed a vertical flux of nitrate into the thermocline of around 2 mmol N m 22 d 21 with the DCM maintained at a depth corresponding to ,5% of surface irradiance (Sharples et al. 2001). The DCM is often observed to be a biomass and photosynthesis maximum as well as a pigment maximum (Holligan et al. 1984a,b;Pemberton et al. 2004;Moore et al. 2006). Monospecific blooms with chlorophyll a (Chl a) concentrations .10 mg Chl a m 23...

show abstract

mentioning

confidence: 62%

Distribution and chromatic adaptation of phytoplankton within a shelf sea thermocline

Hickman

Holligan

Moore

et al. 2009

Limnology & Oceanography

View full text Add to dashboard Cite

show abstract

“…In laboratory studies it has been demonstrated that the photosynthetic action spectra of phytoplankton match spectral growth irradiances (Bidigare et al 1989, Schofield et al 1990). Likewise, field studies have documented that a chl-' (Prezelin et al 1989) and in situ production rates (IOefer & Strickland 1970, Takahashi et al 1989, Prezelin & Glover 1991 are sensitive to the spectral output of the incubation lamps. These observations suggest that white light incubations give minimum estimates of quantum yield and that the lower values are likely related to the spectral bias of the tungsten light source used In photosynthetrons.…”

Section: Utilization Of Light By Phytoplanktonmentioning

confidence: 99%

Variability in spectral and nonspectral measurements of photosynthetic light utilization efficiencies

Schofield¹,

Prézelin²,

Smith³

et al. 1991

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

The aim of this study was to quantify the variability in and differences between spectral and nonspectral measurements: of light utilization efficiencies for natural phytoplankton communities, in order to evaluate possible consequences for blo-opt~cal models of in s j t~l p]-1ma1-y production (P). Field samples were collected at 4 coastal stations durlng a 1 d transect (July 23, 1988) and productivity P(AA,,z) were derived. Significant spatial variability in all bio-optical parameters was noted for communities in the surface waters and the chlorophyll maximum. For surface waters, there was significant variability in the 525 to 600 nm region of the spectral signatures of dl[dA,,z) and P(AA,,z) which was attributable to phycobilins not resolved In absorption spectra. The importance of light absorption by photosynthetic pigments other than chlorophyll a (chl), and thcir assoc~ated Impact upon absorption-based production parameters, increased w~t h light depth. One consequence was a close correspondence between AQ,, and P(AA,,z) at depth w h~c h was not evident in surface waters A second consequence was that while spectrally weighted and whlte l~g h t estimates of quantum yield were occasionally sim~lar In surface waters, spectral estimates for all chlorophyll maximum communities were 4-to 6-fold higher than white light measurements. Results confirm previous observations that white light measures of quantum yield can significantly underestimate quantum yield for subsurface communities of phytoplankton (Prezelin e t al. 1989) a n d provide a conceptual base on which to improve existing and future spectral models of in situ photosynthetic quantum yield.

show abstract

“…Thus, according to its pigment composition, each phytoplankton species should have a characteristic absorption spectrum (Prézelin 1981, Larkum & Barret 1983, Boczar & Prézelin 1989, Johnsen et al 1994, 1997, Porra et al 1997, which may be subject to some modification according to environmental conditions. Chromatic adaptation, that is, adaptation of a given species to particular spectral light conditions, has been reported to occur in the ocean (Glover et al 1986, Takahashi et al 1989, Bidigare et al 1990a. Algae are also able to change the amount of pigment per cell according to the intensity of irradiance to which they are exposed (reviewed in Richardson et al 1983, Falkowski & La Roche 1991.…”

Section: Introductionmentioning

confidence: 99%

Variability in pigment composition and optical characteristics of phytoplankton in the Labrador Sea and the Central North Atlantic

Lutz¹,

Sathyendranath²,

Head³

et al. 2003

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

The relationships between photoadaptation, photoacclimation, cell size and the optical characteristics of the phytoplankton community were studied in 2 areas of the Atlantic Ocean. Pigment composition, absorption and fluorescence excitation spectra were analyzed for samples collected during 2 spring cruises: one in the Labrador Sea and the other in the Central North Atlantic. Photoadaptation (i.e. evolutionary adaptation of different species leading to acquisition of different pigment composition) was evident in the distribution of the main phytoplankton pigments in the area. Photoacclimation (i.e. temporary changes in pigment concentrations in a given species) was also noticeable in the changes in pigment composition and optical characteristics of phytoplankton with changes in depth. Size fractionation of samples from the depth of the chlorophyll a (chl a) maximum showed that, on average, chl a concentration and the values of absorption and fluorescence were dominated by the > 2 µm fraction of phytoplankton. Spectral variations in absorption and fluorescence excitation were, however, similar for the small and for the large size fractions. A distinct regional distribution of algal groups was observed, in which prokaryotic picophytoplankton (size class < 2 µm) dominated in oligotrophic subtropical regions and larger cells (size class > 2 µm) dominated in coastal areas and at higher latitudes. Some significant relationships were observed between the relative abundances of pigments characteristic of certain algal groups and optical properties of the sample. For example, the ratio of absorption at 440 nm to that at 676 nm was positively correlated with the ratio of zeaxanthin to chl a, indicating high abundance of picophytoplankton, especially the cyanobacteria Synechococcus and Prochlorococcus. The ratio of absorption at 555 nm to that at 623 nm was positively correlated with the abundance of phycoerythrin-containing Synechococcus. These results show that useful information about phytoplankton group composition and photoacclimation state can be retrieved from optical properties at a regional scale.

show abstract

Shade and chromatic adaptation of phytoplankton photosynthesis in a thermally stratified sea

Cited by 22 publications

References 9 publications

Distribution and chromatic adaptation of phytoplankton within a shelf sea thermocline

Distribution and chromatic adaptation of phytoplankton within a shelf sea thermocline

Variability in spectral and nonspectral measurements of photosynthetic light utilization efficiencies

Variability in pigment composition and optical characteristics of phytoplankton in the Labrador Sea and the Central North Atlantic

Contact Info

Product

Resources

About