EFFECTS OF VARIATION IN TEMPERATURE. I. ON THE BIOCHEMICAL COMPOSITION OF EIGHT SPECIES OF MARINE PHYTOPLANKTON¹

Abstract

The influence of temperature on the biochemical composition of eight species of marine phytoplankton was investigated. Thalassiosira pseudonana Hasle and Heim‐dal, Phaeodactylum tricornutum Bohlin and, Pavlova lutheri Droop (three of eight species studied) had minimum values of carbon and nitrogen quotas at intermediate temperatures resulting in a broad U‐shaped response in quotas over the temperature range of 10 to 25°C. Protein per cell also had minimum values at intermediate temperatures for six species. For T. pseudonana, P. tricornutum, and P. lutheri, patterns of variation in carbon, nitrogen, and protein quotas as a function of temperature were similar. Over all species, lipid and carbohydrate per cell showed no consistent trends with temperature. Only chlorophyll a quotas and the carbon: chlorophyll a ratios (θ) showed consistent trends across all species. Chlorophyll a quotas were always lower at 10°C than at 25°C. Carbon: chlorophyll a ratios (θ) were always higher at 10°C than at 25°C. We suggest that although θ consistently increases at lower temperatures, the relationship between temperature and θ ranges from linear to exponential and is species specific. Accordingly, the interspecific variance in θ that results from species showing a range of possible responses to temperature increases as temperature declines and reaches a maximum at low temperatures. High photon flux densities appear to increase the potential interspecific variance in the carbon: chlorophyll a ratio and therefore exacerbate these trends.

Thermal Performance Curves of Functional Traits Aid Understanding of Thermally Induced Changes in Diatom-Mediated Biogeochemical Fluxes

“…Furthermore, maximum growth rates were comparable to previously reported values for this strain; ∼0.9 d −1 at 18 • C and 80 µmol photons m −2 sec −1 (Li and Campbell, 2013). In contrast to other studies, we found that the thermal optimum range (17.0 and 20.1 • C, centered on 18.6 • C) was slightly colder than previously reported values (Thompson et al, 1992;Boyd et al, 2015) and may be due to the lower growth irradiance used in our study (Sandnes et al, 2005). In terms of morphological traits, absolute cell volumes were within range of previously reported values (Li and Campbell, 2013) and consistent with Thompson et al (1992), with cells becoming larger with increasing temperature (Figure 3A).…”

“…In contrast to other studies, we found that the thermal optimum range (17.0 and 20.1 • C, centered on 18.6 • C) was slightly colder than previously reported values (Thompson et al, 1992;Boyd et al, 2015) and may be due to the lower growth irradiance used in our study (Sandnes et al, 2005). In terms of morphological traits, absolute cell volumes were within range of previously reported values (Li and Campbell, 2013) and consistent with Thompson et al (1992), with cells becoming larger with increasing temperature (Figure 3A). These changes in cell volume, although small (i.e., ∼10%), may have significant implications for vertical export of carbon, as has been demonstrated in other small, spherical phytoplankton taxa (coccolithophores; Pantorno et al, 2013).…”

Effects of temperature, nitrogen, and light limitation on the optical properties of the marine diatom Thalassiosira pseudonana

“…For example, the U-shaped pattern of cellular carbon and nitrogen, the linear pattern of increasing C : N, and the general trend of Chl a to increase and C : Chl a to decrease with increasing temperature were observed by Thompson et al (1992). The reduction in nitrogen and Chl a quotas accompanied by an increase in C : N and C : Chl a ratios for T. pseudonana grown either under N limitation or saturating light is also well documented (Eppley and Renger 1974;Berges and Harrison 1995;Reynolds et al 1997).…”

“…The observed patterns in a and a result primarily from * Chl the acclimative strategies of T. pseudonana where there is an increase in Chl a content in response to light limitation and a decrease in Chl a in response to temperature and nitrogen limitation (Sakshaug et al 1987;Thompson et al 1992;Reynolds et al 1997). Changes in the absorption cross-section of cells can be explained in terms of variations in cell size and the imaginary part of the refractive index, nЈ.…”

Effects of Environmental Factors and Nutrient Availability on the Biochemical Composition of Algae for Biofuels Production: A Review

“…Environmental factors such as temperature, light, pH, and nutrients not only affect photosynthesis and growth rate of the algae, but also influence the activity of cellular metabolism and composition. These effects have been identified individually by researchers [25][26][27][28][29][30][31], however, no consolidated review on the effect of these factors on algae is available. Most of the recent reviews have focused on production and processing techniques [11,16,32] with few data on the impacts of environmental and nutritional factors on algal growth rates.…”