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Climate Effects on High Latitude Daphnia via Food Quality and Thresholds.

Przytulska A, Bartosiewicz M, Rautio M, Dufresne F, Vincent WF - PLoS ONE (2015)

Bottom Line: We also compared the direct effect of temperature on both Daphnia clones feeding on eukaryotic picoplankton (Nannochloropsis).The food threshold for growth of the high latitude Daphnia was 3.7 (18°C) to 4.2 (26°C) times higher when fed Synechococcus versus Nannochloropsis, and there was also a significant negative effect of increased temperature and cyanobacterial food on zooplankton fatty acid content and composition.The combined effect of temperature and food quality on the performance of the high latitude Daphnia was greater than their effects added separately, further indicating the potentially strong indirect effects of climate warming on aquatic food web processes.

View Article: PubMed Central - PubMed

Affiliation: Centre d'études nordiques (CEN), Université Laval, Québec, Québec, Canada; Département de biologie, Université Laval, Québec, Québec, Canada.

ABSTRACT
Climate change is proceeding rapidly at high northern latitudes and may have a variety of direct and indirect effects on aquatic food webs. One predicted effect is the potential shift in phytoplankton community structure towards increased cyanobacterial abundance. Given that cyanobacteria are known to be a nutritionally poor food source, we hypothesized that such a shift would reduce the efficiency of feeding and growth of northern zooplankton. To test this hypothesis, we first isolated a clone of Daphnia pulex from a permafrost thaw pond in subarctic Québec, and confirmed that it was triploid but otherwise genetically similar to a diploid, reference clone of the same species isolated from a freshwater pond in southern Québec. We used a controlled flow-through system to investigate the direct effect of temperature and indirect effect of subarctic picocyanobacteria (Synechococcus) on threshold food concentrations and growth rate of the high latitude clone. We also compared the direct effect of temperature on both Daphnia clones feeding on eukaryotic picoplankton (Nannochloropsis). The high latitude clone had a significantly lower food threshold for growth than the temperate clone at both 18 and 26°C, implying adaptation to lower food availability even under warmer conditions. Polyunsaturated fatty acids were present in the picoeukaryote but not the cyanobacterium, confirming the large difference in food quality. The food threshold for growth of the high latitude Daphnia was 3.7 (18°C) to 4.2 (26°C) times higher when fed Synechococcus versus Nannochloropsis, and there was also a significant negative effect of increased temperature and cyanobacterial food on zooplankton fatty acid content and composition. The combined effect of temperature and food quality on the performance of the high latitude Daphnia was greater than their effects added separately, further indicating the potentially strong indirect effects of climate warming on aquatic food web processes.

No MeSH data available.


Related in: MedlinePlus

The content and composition of FA in Daphnia-HL fed either Nannochloropsis (N) or Synechococcus (S) at 18°C or 26°C.Each values is a mean of 5 replicates ±SE. Different letters indicate significant differences in total fatty acid contents at p<0.01 (two-way ANOVA with Tukey HSD).
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pone.0126231.g004: The content and composition of FA in Daphnia-HL fed either Nannochloropsis (N) or Synechococcus (S) at 18°C or 26°C.Each values is a mean of 5 replicates ±SE. Different letters indicate significant differences in total fatty acid contents at p<0.01 (two-way ANOVA with Tukey HSD).

Mentions: The elevated temperature resulted in a significant decrease of body fatty acids (FA) in Daphnia-HL feeding on either Nannochloropsis or Synechococcus (Table 2, Fig 4). The animals feeding on Nannochloropsis accumulated more FA than those feeding on Synechococcus at each temperature (Fig 4). There was also a significant effect of the interaction of food and temperature on total body FA content (Table 2).


Climate Effects on High Latitude Daphnia via Food Quality and Thresholds.

Przytulska A, Bartosiewicz M, Rautio M, Dufresne F, Vincent WF - PLoS ONE (2015)

The content and composition of FA in Daphnia-HL fed either Nannochloropsis (N) or Synechococcus (S) at 18°C or 26°C.Each values is a mean of 5 replicates ±SE. Different letters indicate significant differences in total fatty acid contents at p<0.01 (two-way ANOVA with Tukey HSD).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4430472&req=5

pone.0126231.g004: The content and composition of FA in Daphnia-HL fed either Nannochloropsis (N) or Synechococcus (S) at 18°C or 26°C.Each values is a mean of 5 replicates ±SE. Different letters indicate significant differences in total fatty acid contents at p<0.01 (two-way ANOVA with Tukey HSD).
Mentions: The elevated temperature resulted in a significant decrease of body fatty acids (FA) in Daphnia-HL feeding on either Nannochloropsis or Synechococcus (Table 2, Fig 4). The animals feeding on Nannochloropsis accumulated more FA than those feeding on Synechococcus at each temperature (Fig 4). There was also a significant effect of the interaction of food and temperature on total body FA content (Table 2).

Bottom Line: We also compared the direct effect of temperature on both Daphnia clones feeding on eukaryotic picoplankton (Nannochloropsis).The food threshold for growth of the high latitude Daphnia was 3.7 (18°C) to 4.2 (26°C) times higher when fed Synechococcus versus Nannochloropsis, and there was also a significant negative effect of increased temperature and cyanobacterial food on zooplankton fatty acid content and composition.The combined effect of temperature and food quality on the performance of the high latitude Daphnia was greater than their effects added separately, further indicating the potentially strong indirect effects of climate warming on aquatic food web processes.

View Article: PubMed Central - PubMed

Affiliation: Centre d'études nordiques (CEN), Université Laval, Québec, Québec, Canada; Département de biologie, Université Laval, Québec, Québec, Canada.

ABSTRACT
Climate change is proceeding rapidly at high northern latitudes and may have a variety of direct and indirect effects on aquatic food webs. One predicted effect is the potential shift in phytoplankton community structure towards increased cyanobacterial abundance. Given that cyanobacteria are known to be a nutritionally poor food source, we hypothesized that such a shift would reduce the efficiency of feeding and growth of northern zooplankton. To test this hypothesis, we first isolated a clone of Daphnia pulex from a permafrost thaw pond in subarctic Québec, and confirmed that it was triploid but otherwise genetically similar to a diploid, reference clone of the same species isolated from a freshwater pond in southern Québec. We used a controlled flow-through system to investigate the direct effect of temperature and indirect effect of subarctic picocyanobacteria (Synechococcus) on threshold food concentrations and growth rate of the high latitude clone. We also compared the direct effect of temperature on both Daphnia clones feeding on eukaryotic picoplankton (Nannochloropsis). The high latitude clone had a significantly lower food threshold for growth than the temperate clone at both 18 and 26°C, implying adaptation to lower food availability even under warmer conditions. Polyunsaturated fatty acids were present in the picoeukaryote but not the cyanobacterium, confirming the large difference in food quality. The food threshold for growth of the high latitude Daphnia was 3.7 (18°C) to 4.2 (26°C) times higher when fed Synechococcus versus Nannochloropsis, and there was also a significant negative effect of increased temperature and cyanobacterial food on zooplankton fatty acid content and composition. The combined effect of temperature and food quality on the performance of the high latitude Daphnia was greater than their effects added separately, further indicating the potentially strong indirect effects of climate warming on aquatic food web processes.

No MeSH data available.


Related in: MedlinePlus