title: Increased risk of phosphorus limitation at higher temperatures for Daphnia magna.
abstract: Invertebrate herbivores frequently face growth rate constraints due to their high demands for phosphorus (P) and nitrogen (N). Temperature is a key modulator of growth rate, yet the interaction between temperature and P limitation on somatic growth rate is scarcely known. To investigate this interaction, we conducted a study on the somatic growth rate (SGR) of the cladoceran Daphnia magna, known to be susceptible to P-limitation. We determined the SGR across a broad range of dietary P content of algae (carbon (C):P ratios (125-790), and at different temperatures (10-25°C). There was a strong impact of both temperature and C:P ratio on the SGR of D. magna, and also a significant interaction between both factors was revealed. The negative effect of dietary C:P on growth rate was reduced with decreased temperature. We found no evidence of P limitation at lowest temperature, suggesting that enzyme kinetics or other measures of food quality overrides the demands for P to RNA and protein synthesis at low temperatures. These findings also indicate an increased risk of P limitation and thus reduced growth efficiency at high temperatures.
authors.affiliation: Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, Oslo, Norway. jonas.persson@bio.uio.no
authors.forename: Jonas
authors.initials: J
authors.lastname: Persson
authors.forename: Marcin Włodzimierz
authors.initials: MW
authors.lastname: Wojewodzic
authors.forename: Dag Olav
authors.initials: DO
authors.lastname: Hessen
authors.forename: Tom
authors.initials: T
authors.lastname: Andersen
mesh_terms: D000818:Animals; D002244:Carbon / Q000378:metabolism; D003621:Daphnia / Q000254:growth & development / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism*; D012621:Seasons; D013696:Temperature
chemical_list: D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen
references.citation: Proc Natl Acad Sci U S A. 2004 Jul 27;101(30):11001-6
references.pmid: 15213326
references.citation: Oecologia. 2003 Aug;136(3):336-46
references.pmid: 12827486
references.citation: Limnol Oceanogr. 2009 Nov;54(6):2283-2297
references.pmid: 20396409
references.citation: Oecologia. 1984 Aug;63(3):300-306
references.pmid: 28311203
references.citation: Trends Ecol Evol. 2004 Feb;19(2):101-8
references.pmid: 16701236
references.citation: Ecol Lett. 2007 Dec;10(12):1154-63
references.pmid: 17927772