Khattack et al. 2018 Lupin.pdf (1.18 MB)
Download fileThe threshold elemental ratio of carbon and phosphorus of Daphnia magna and its connection to animal growth
journal contribution
posted on 2018-12-17, 15:04 authored by Hamza K. Khattak, Clay Prater, Nicole D. Wagner, Paul C. FrostThe growth of animal consumers is afected by the balance of elements in their diet with the transition
between limitation by one element to another known as the threshold elemental ratio (TER). Precise
estimates of TERs with known levels of uncertainty have yet to be generated for most zooplankton
consumers. We determined the TER for carbon (C) and phosphorus (P) in for a common lake zooplankter,
Daphnia magna, using experimental measurements and theoretical considerations. Daphnia growth
responses to food C:P ratios across a relatively narrow range (80–350) generated an empirical estimate
of TERC:P of 155±14. While this TER matched our modelled estimate of TERC:P (155±16), it was lower
than previous estimates of this dietary transition point. No threshold was found when we examined
daphnid body C:N or C:P ratios in response to changing food C:P ratios, which indicates P-limitation at
even lower food C:P ratios. Our results provide strong evidence that D. magna is likely to experience
acute P-limitation when food C:P ratios exceed even relatively low ratios (~155). Our model further
demonstrated that while physiological adjustments may reduce the likelihood of P-limitation or reduce
its intensity, these changes in animal material processing would be accompanied by reduced maximum
growth rates.
Funding
Support for this research was provided by the Natural Sciences and Engineering Research Council of Canada through funds provided to Hamza Khattak and Paul Frost.
History
School
- Social Sciences
Department
- Geography and Environment
Published in
Scientific ReportsVolume
8Issue
1Citation
KHATTAK, H.K. ... et al., 2018. The threshold elemental ratio of carbon and phosphorus of Daphnia magna and its connection to animal growth. Scientific Reports, 8: 9673.Publisher
© The authors. Published by Springer NatureVersion
- VoR (Version of Record)
Publisher statement
This work is made available according to the conditions of the Creative Commons Attribution 4.0 International (CC BY 4.0) licence. Full details of this licence are available at: http://creativecommons.org/licenses/ by/4.0/Acceptance date
2018-06-05Publication date
2018Notes
This is an Open Access Article. It is published by Springer under the Creative Commons Attribution 4.0 Unported Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/eISSN
2045-2322Publisher version
Language
- en