Quantifying nutrient throughput and DOM production by algae in continuous culture
Name
1-s2.0-S0022519320300692-main.pdf
Description
Published version
Size
11.41 MB
Format
Adobe PDF
Checksum (MD5)
f6475ae4a4a0cfb54e42cccdcfdc3d2b
Author(s)
Omta, AW
Talmy, D
Inomura, K
Irwin, AJ
Finkel, ZV
Sher, D
Liefer, JD
Follows, MJ
Date Issued
2020
Journal
Journal of Theoretical Biology
Publisher
Elsevier BV
Version
Final published version
Abstract
© 2020 Freshwater and marine algae can balance nutrient demand and availability by regulating uptake, accumulation and exudation. To obtain insight into these processes under nitrogen (N) and phosphorus (P) limitation, we reanalyze published data from continuous cultures of the chlorophyte Selenastrum minutum. Based on mass budgets, we argue that much of the non‐limiting N and P had passed through the organisms and was present as dissolved organic phosphorus or nitrogen (DOP or DON). We construct a model that describes the production of biomass and dissolved organic matter (DOM) as a function of the growth rate. A fit of this model against the chemostat data suggests a high turnover of the non‐limiting N and P: at the highest growth rates, N and P atoms spent on average only about 3 h inside an organism, before they were exuded as DON and DOP, respectively. This DOM exudation can explain the observed trends in the algal stoichiometric ratios as a function of the dilution rate. We discuss independent evidence from isotope experiments for this apparently wasteful behavior and we suggest experiments to quantify and characterize DON and DOP exudation further.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1016/j.jtbi.2020.110214
