Phytoplankton stoichiometry

Abstract

Because phytoplankton live at the interface between the abiotic and the biotic compartments of ecosystems, they play an important role in coupling multiple nutrient cycles. The quantitative details of how these multiple nutrient cycles intersect is determined by phytoplankton stoichiometry. Here we review some classic work and recent advances on the determinants of phytoplankton stoichiometry and their role in determining ecosystem stoichiometry. First, we use a model of growth with flexible stoichiometry to reexamine Rhee and Goldman's classic chemostat data. We also discuss a recent data compilation by Hall and colleagues that illustrates some limits to phytoplankton flexibility, and a model of physiological adaptation that can account for these results. Second, we use a model of resource allocation to determine the how the optimal nitrogen-tophosphorus stoichiometry depends on the ecological conditions under which species grow and compete. Third, we discuss Redfield's mechanism for the homeostasis of the oceans' nitrogen-to-phosphorus stoichiometry and show its robustness to additional factors such as iron-limitation and temporal fluctuations. Finally, we suggest areas for future research.

Processes and patterns of oceanic nutrient limitation

“…In particular, changes in the relative availabilities of trace metals during redox transitions in ancient oceans have left imprints on the metal-binding proteomes, and hence trace-metal requirements, of modern organisms 1,10,32,39 . Ratios of C:N:P also vary between taxa, potentially reflecting ecological trade-offs in the allocation of carbon (and associated nutrients) amongst macromolecules associated with different functions [9][10][11]35 . The availability of nutrients in the environment also drives extensive phenotypic differences in cellular composition 2,9,[36][37][38] .…”

Southern Ocean phytoplankton physiology in a changing climate

“…This irregularity in nutrient availability greatly influences the spatial dynamics of biological communities and more specifically, the regulation of marine primary production (Hiscock et al, 2003). In phytoplankton, variations in nutrient ratios (elemental stoichiometry) will reflect their under-lying allocation of energy into major molecules (RNA, cellulose, lipids, proteins etc) and are closely associated with key traits such as growth rate, and size (Klausmeier et al, 2008;Finkel et al, 2009). Therefore, alterations in elemental ratios can have large effects on rates and efficiencies of energy transfer and elemental cycling in the ocean.…”

“…Therefore, alterations in elemental ratios can have large effects on rates and efficiencies of energy transfer and elemental cycling in the ocean. Furthermore, through their influence on cell metabolism, nutrient dynamics can alter competitive advantages and thus species dominance and community structure (Klausmeier et al, 2008).…”

Asynchrony of spring phytoplankton response to temperature driver within a spatial heterogeneity bay of Three-Gorges Reservoir, China

“…Phytoplankton live at the interface between the abiotic and the biotic compartments of ecosystems, they play an important role in multiple nutrient cycles (Klausmeier et al, 2008). As one of the dominant features in the seasonal growth patterns of phytoplankton of oceans and lakes, spring phytoplankton bloom is particularly important with respect to food web dynamics of aquatic systems, so that the controlling mechanisms of spring phytoplankton succession has been received much attention (Henson et al, 2006;Ferris and Lehman, 2007;Peeters et al, 2007a;Nicklisch et al, 2008;Sommer and Lengfellner, 2008).…”