The effects of Copper and Zinc on survival, growth and reproduction of the cladoceran Daphnia longispina: introducing new data in an “old” issue

Abstract

Metal contamination is still a major environmental issue due to their continuous deposition and persistence. In this work we intended to assess the impact that Copper (Cu) and Zinc (Zn) exert in life-history parameters of Daphnia longispina, a common cladoceran in freshwater environments. Thus, we studied the effects of Cu (20-300 µg/L) and Zn (500-4000 µg/L) on the survival, growth, reproduction, feeding rate and population growth rate of D. longispina. Though survival was only reduced for the highest concentration of each metal, other endpoints were strongly affected by lower concentrations. Growth was affected by both metals, especially in the period 0-7 d, being significant for Cu ≥ 40 µg/L and Zn ≥ 500 µg/L. Indeed, growth endpoints at day 7 (body length and growth rate) were equally or more sensitive than the corresponding endpoints at day 21. The size at first reproduction decreased (significant for Cu ≥ 40 µg/L and Zn ≥ 500 µg/L). Reproduction decreased, which was partially explained by the reduced growth, but additional effects were supported by a direct effect of metals on reproduction (based on the relationship body length-brood size). Reduced growth and reproduction are likely a food mediated effect due to feeding inhibition caused by the metals. Globally, the studied endpoints were affected by Cu and Zn differently, supporting a chemical-specificity of the effects, with Zn causing more pronounced effects than Cu. This work presents an innovative approach to the effects of Cu and Zn to D. longispina, giving a general and comprehensive overview of those effects.

Intercontinental genomic parallelism in multiple three-spined stickleback adaptive radiations

“…We expected trophic morphology to evolve in response to zooplankton communities, which can vary in response to water chemistry ( 34 , 35 ), particularly Zn. In agreement, we found parallel, inverse associations between gill raker number and Zn (F 1,71 = 63.6, FDR = <0.001, σ 2 explained = 53.4%).…”

Development and Validation of a Mixture Toxicity Implementation in the Dynamic Energy Budget–Individual‐Based Model: Effects of Copper and Zinc on Daphnia magna Populations

“…The most likely physiological mode of action for Cu that explains the observed decrease in reproduction and growth at the individual level (standard test) was the decrease in energy assimilation (see Modeling results of the single substances in the Results section). Indeed, the effect of Cu on D. magna has been suggested to be related to reduced energy acquisition (De Schamphelaere et al 2007b; Martins et al 2017) or declining filtration rates (Ferrando and Andreu 1993). This decrease in energy assimilation due to Cu eventually resulted in a significant decrease in population growth in the early phases of the experiment.…”

The Chronic Effects of Copper and Cadmium on Life History Traits Across Cladocera Species: A Meta-analysis

“…Cladocerans, and particularly Daphnia species, are classic test organisms for evaluating the sublethal effects of metals, which globally represent a serious problem to the aquatic food chain and water quality (Sarma and Nandini 2006; Altshuler et al 2011; Martins et al 2017). The sublethal levels of metals have received a great deal of attention, because they cause a range of ecotoxicological effects on those species.…”

“…Anthropogenic and natural processes introduce a great deal of pollutants and stress into natural ecosystems (Mountouris et al 2002; Demirak et al 2006; Dedourge-Geffard et al 2009; Martins et al 2017). Over the past few decades, trace levels of metals have received much attention (Jing et al 2006), because they generate negative biological effects on aquatic organisms, such as algae grazers and subsequently alter water quality.…”