The stoichiometry of carbon, nitrogen, and phosphorus in particulate matter of lakes and oceans

Abstract

The mean carbon, nitrogen, and phosphorus contents of particulate material for 5 1 lakes or lake basins, extending from arctic to tropical climatic regions, including small lakes as well as the largest lakes in the world, indicate that Redfield ratios are the exception rather than the rule in freshwater. The C: P and N : P ratios are more variable for lake particles but generally higher than marine particles, and the mean molar C: N, C: P, and N : P ratios are substantially higher than the Redfield ratio of 106 : 16: 1. On average, lower C : N, C : P, and N : P ratios occur in subarctic lakes while higher ratios occur in the tropics and in temperate, oligotrophic lakes on the Canadian Shield. In shield lakes with long residence times (>6 months) the high ratios of C : N, C : P, and N : P do not originate from streamborne or atmospherically deposited particles but arise from in-lake processes. Regression analysis demonstrates that small lakes are generally more N and P deficient than large lakes. In freshwaters, particulate composition ratios imply that a wide variety of conditions exists in lakes, including N and P deficiency, as well as N and P sufficiency. In the Experimental Lakes Area of Canada, independent physiological nutrient status indicators generally agree with the status indicated by seston ratios. The relative uniformity of marine C : N : P composition (compared to lakes) at the Redfield ratio suggests that marine plankton cannot be as severely, or as frequently, limited by N and P as lake plankton. Consequently, the paradigm of N limitation in the oceans requires qualification.Based on particulate comDosition, it is more correct to say that ocean plankton is noi as N grid P deficient as lake-plankton.The composition of marine particulate matter is relatively uniform. Redfield (1934Redfield ( , 1958 noted the near constancy of the ratio of C : N : P in marine plankton and the similarity of the N : P ratio of plankton to the oceanic deepwater ratio of nitrate to phosphate. As early as 1940, the C : N : P molar composition ratio of marine plankton was accepted to be 106 : 16 : 1 (Redfield et al. 1963); this ratio is now referred to as the Redfield ratio. The ratio has withstood the test of time, and the ever-growing number of analyses of marine particles and nutrient regeneration profiles, with relatively AcknowledgmentsWe thank G. J. Bumskill and H. E. Welch for permission to publish particulate C, N, and P data on Lake Winnipeg and the Saqvaqjuac lakes, respectively. Dana Cruikshank and his field assistants sampled the ELA lakes for us.

Mapping the distribution, biomass and tissue nutrient levels of a marine benthic cyanobacteria bloom (Lyngbya majuscula)

“…The C : P ratios (415-691; 396-660 adjusted for carbonate) and N : P ratios (26-72) in the present study (Fig. 8b, c), are within the commonly quoted ranges for phosphorus limitation of benthic marine microalgae (C : P > 180 and N : P > 22; Hillebrand and Sommer 1999), freshwater periphyton (C : P > 369 and N : P > 32; Kahlert 1998) and severe phosphorus limitation of phytoplankton (C : P > 258, N : P > 22) (Hecky et al 1993). Thus, the high C : P ratios (combined with high N : P ratios and low phosphorus contents) of L. majuscula in the present study strongly support phosphorus limitation of L. majuscula in Deception Bay.…”

“…8b) in the current study are similar to ratios (46-51) reported from Deception Bay in 2005 but are higher than the ratio (14) reported for Deception Bay in 1999-2000 (Watkinson et al 2005) and the Eastern Banks (16.4-22.4) (Ahern et al 2007). The N : P ratios reported in the present study, particularly during the incipient, rapid growth and plateau phases (47-72), were substantially higher than the various optimum N : P ranges published in the literature, including optimum ratios for unicellular phytoplankton (16) (Redfield et al 1963), freshwater periphyton (18) (Hecky et al 1993), medium ratio (30) for benthic plants (Atkinson and Smith 1983) and the optimum range (13-22) for benthic microalgae (Hillebrand and Sommer 1999). The higher N : P ratios recorded in the present study are not unusual for nitrogen-fixing species, which have often been documented as having higher N : P stoichiometry than non-diazotrophic species (Table 4).…”

“…Although very limited data are available on the stoichiometry or range of elemental ratios for L. majuscula and other benthic marine nitrogen-fixing cyanobacteria, comparison to critical values developed for phytoplankton (Redfield et al 1963;Hecky et al 1993), freshwater periphyton (Kahlert 1998) and marine microalgae (Hillebrand and Sommer 1999) can provide some insight into the physiology and nutritional status of L. majuscula. The C : N ratio of L. majuscula in the current study was relatively consistent (9.8-10.5; 9.4-10 adjusted for carbonate) and had very low standard errors during the incipient, rapid growth and plateau phases of the bloom (Fig.…”

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“…Biomass stoichiometry is a useful tool for detecting nutrient limitation and has been widely applied to phytoplankton (Hecky et al, 1993). Recently, this concept has been transferred to benthic microalgae (Kahlert, 1998;Hillebrand & Sommer, 1999).…”

On the estimation of transport timescales – case study: the Dez reservoir

“…These confusions are the result of ignoring the underlying concept used (e.g. Hecky et al 1993) or idealizing the circumstances that are constrained by critical assumptions (e.g. Andrews & Muller 1983).…”