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An empirical model of the phytoplankton chlorophyll : carbon ratio-the conversion factor between productivity and growth rate

James E. Cloern·Christian Grenz·Lisa Vidergar-Lucas
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Abstract

We present an empirical model that describes the ratio of phytoplankton chlorophyll a to carbon, Chl: C, as a function of temperature, daily irradiance, and nutrient-limited growth rate. Our model is based on 219 published measurements of algal cultures exposed to light-limited or nutrient-limited growth conditions. We illustrate an approach for using this estimator of Chl: C to calculate phytoplankton population growth rate from measured primary productivity. This adaptive Chl: C model gives rise to interactive light-nutrient effects in which growth efficiency increases with nutrient availability under low-light conditions. One implication of this interaction is the enhancement of phytoplankton growth efficiency, in addition to enhancement of biomass yield, as a response to eutrophication.

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James E. Cloern, Christian Grenz, Lisa Vidergar-Lucas. 2003-12-22. An empirical model of the phytoplankton chlorophyll : carbon ratio-the conversion factor between productivity and growth rate. https://doi.org/10.4319/lo.1995.40.7.1313

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