Scale‐dependent carbon:nitrogen:phosphorus seston stoichiometry in marine and freshwaters

Abstract

The classical Redfield ratio of carbon 106 : nitrogen 16 : phosphorus 1 is a cornerstone of biogeochemistry. With the use of .2,000 observations of the chemistry of particulate matter from small and large lakes, as well as nearand off-shore marine environments, we found that the best model to describe seston stoichiometry depended on the scale of analysis. We also found that there were better estimates for seston chemistry than the classical ratio for all habitats, whether freshwater or marine. Across the entire data set, a constant proportionality of C 166 : N 20 : P 1 (6error) described the data, which implies higher C sequestration per unit of N and P in surface waters than given in the classical ratio. At a regional scale, however, C : P and C : N often declined with increasing seston abundance, rejecting a constant ratio model. Within both freshwater and marine habitats, higher seston abundance is often associated with lower C : P and C : N ratios (higher nutrient content). The difference in appropriateness of the constant ratio model with respect to the entire data compared with subsets of the data indicates a scale dependence in stoichiometric relationships in seston C : N : P ratios. Given these consistent shifts in seston chemistry with particle abundance, the narrower variation in seston chemistry associated with marine seston chemistry could occur because of a reduced range of particulate nutrient concentration. For all but the largest scales, the classical Redfield model of biogeochemical cycling should be replaced with a more general power function model.

An optimality model of photoadaptation in contrasting aquatic light regimes

“…Although phosphorus-tonitrogen-to-carbon stoichiometry is often assumed constant after the work of Redfield (1958), numerous studies have shown significant deviation from the value first established of 1 : 16 : 106 (Sterner et al 2008). Indeed, it is well known that phytoplankton N : C ratios change in response to light and nutrient limitation (Laws and Bannister 1980).…”

Food quality dominates the impact of food quantity on Daphnia life history: possible implications for re-oligotrophication

“…For example, where algae are known for their stoichiometric flexibility, zooplankton and higher trophic levels often have a lower carbon to phosphorus ratio (C:P) and display a much narrower range (DeMott et al 1998, Sterner et al 2008, van de Waal et al 2010. This can create stoichiometric bottlenecks, where zooplankton production is not limited by energy (C) but by nutrients such as nitrogen (N) and especially P when they feed on algae of high C:P.…”

Possible nutrient limiting factor in long term operation of closed aquatic ecosystem

“…Carbon is the main composite of the algae protoplasm, as evidenced by the classical description of C 106 H 263 O 110 N 16 P 1 or better estimated by the Redfield ratio C 166 : N 20 : P 1 (±error) (Sterner et al, 2008). C supply usually exceeds the demand in open ecological systems, while N and P often become the limiting elements (Guildford et al, 2007).…”