Influence of Seasonal Variations of Temperature and Light on the Growth Rate of Cultures and Natural Populations of Intertidal Diatoms

Abstract

Cultures of four benthic diatom species (Navicula salinarum, Amphiprora cf, paludosa, N. arenaria, Gyrosigma spenceni) were kept at the surface of a mudflat in order to measure division rates. During incubations in the period of December to June the mean temperature was the predominant factor regulating cell division rate. Immersion of the mudflat with very turbid tidal water was an important factor only at a low-level mudflat station during winter and early spring. Strong temperature fluctuations during incubations, with periods of frost in winter and periods of insolation during hot summer weather, did not interrupt growth of the cultures. Hence high temperatures and high irradiance values are unlikely to be the direct cause of the summer minimum in population density that is frequently observed in the estuary. After the winter minimum the increase in population density was measured at three levels of the mudflat. At the high-level station the density increased in January at still very low temperatures, whereas at the mid-and low-level stations this increase started in March. This observation indicates that the emersion time of the mudflat and hence its exposure to full daylight is an important factor in the development of the spring bloom. The density of the diatom populations in the 0.5 cm top layer of the sediment increased only at a very low rate (with maximum rates of ca. 0.1 doublings d-l). Low photosynthetic rates of natural diatom populations in the sediment core are the cause of these low doubling rates of natural populations on the mudflat. Dispersal of diatom cells into the sediment is probably responsible for the decreased photosynthetic rates and, consequently, for the low doubling rates of sediment-inhabiting diatoms.

Temporal variations in microbenthic metabolism and inorganic nitrogen fluxes in sandy and muddy sediments of a tidally dominated bay in the northern Wadden Sea

“…Admiraal & Peletier, 1980;Rasmussen et al, 1983;van Duyl & Kop, 1990), while relatively few have examined the simultaneous community response towards a number of dominating parameters (e.g. Hargrave et al, 1983;Grant, 1986;Kristensen, 1993).…”

Growth characterization of non-photosynthetic diatoms, <i>Nitzschia</i> spp., inhabiting estuarine mangrove forests of Ishigaki Island, Japan

“…Diatoms are known to have adapted to a wide range of temperatures (e.g., Thomas 1966, Colijn & van Buurt 1975, Admiraal & Peletier 1980, Suzuki & Takahashi 1995, Mock & Hoch 2004, Boyd et al 2013, Thorel et al 2014, Woelfel et al 2014. The non-photosythetic diatoms investigated in the present study are capable of surviving at temperatures from 5 to 35°C, which is wider than that reported for a strain of a closely related species, such as Pseudo-nitzschia australis Frengulli, which has been reported to be capable of growing from 5 to 20°C (Thorel et al 2014).…”

“…This evaporation phenomenon also triggers other severe conditions such as high temperature and high salinity. Nevertheless, it has been reported that various algal species are capable of inhabiting such severe environments (Williams 1964, Mizuno 1992, Colijn & van Buurt 1975, Admiraal & Peletier 1980, Pinckney & Zingmark 1991, Kamikawa et al 2015a.…”

Interaction between Estuarine Microphytobenthos and Physical Forcings: The Role of Atmospheric and Sedimentary Factors

“…However, the inverse relationships between microphytobenthic biomass and temperature and SR (Figure 3), clearly point to optimal conditions for the establishment of dense populations of cyanobacteria and diatoms, as being in the lower ranges of these two parameters. Accordingly it has been pointed [33] that the temporal distribution of microphytobenthos can be explained partly by the seasonal variation in irradiance and sediment temperature. Studying the influence of different grain sizes and temperatures on the growth of benthic cyanobacteria and diatoms it was found [34] that diatoms achieved the highest biomass on the finest sediments (<63 µm), in a temperature range of 10˚C -15˚C, while cyanobacteria achieved low biomass levels in the same temperature range.…”