Effects of increased temperatures on Gammarus fossarum under the influence of copper sulphate

Abstract

The specialised fauna of freshwater springs will have to cope with a possible temperature rise owing to Global Change. It is affected additionally by contamination of the water with xenobiotics from human activities in the surrounding landscape. We assessed the combined effects of temperature increase and exposure to toxins in laboratory experiments by using copper sulphate as a model substance and Gammarus fossarum Koch, 1835, as the model organism. This amphipod is a common representative of the European spring fauna and copper ions are widespread contaminants, mainly from agricultural practice. The experiments were conducted in boxes placed in flow channels and the water temperatures were varied. The gammarids were fed with conditioned beech leaf discs. The feeding activity of the amphipods was quantified on the level of the organism; and the respiratory electron transport system (ETS) assay was conducted in order to determine changes on the cellular level in the test organisms. The results show that the feeding activity increased slightly with higher water temperature. The sub-lethal copper dose had no significant effect other than a trend towards lower feeding activity. The ETS activity was significantly higher at the higher water temperatures, and the copper ions significantly lowered the ETS activity of the organisms. The combination of the two methods was useful when testing for combined effects of environmental changes and pollutants on a species. From the results one can reasonably infer a higher risk of adverse effects with increase in water temperature and exposure to a particular heavy metal.

Additive effects of temperature and infection with an acanthocephalan parasite on the shredding activity of Gammarus fossarum (Crustacea: Amphipoda): the importance of aggregative behavior

“…Considering that the thermal optimum for G. fossarum is approximately 11.5°C (P€ ockl & Humpesch, 1990), with potential variations depending on the geographical origin of the population (Foucreau et al, 2013b(Foucreau et al, , 2014, it is not surprising that a temperature of 18°C would induce a nonlethal thermal stress, with consequences on food consumption. Similarly, Schmidlin et al (2015b) observed a slightly reduced feeding activity of G. fossarum above 16°C, while that of males Dikerogammarus villosus decreased between 20 and 25°C (Pellan et al, 2015).…”

“…Similarly, Schmidlin et al . () observed a slightly reduced feeding activity of G. fossarum above 16 °C, while that of males Dikerogammarus villosus decreased between 20 and 25 °C (Pellan et al ., ).…”

Copper sulphate reduces the metabolic activity of Gammarus fossarum in laboratory and field experiments

“…It is generally agreed that organisms living under environmental conditions that are near to their tolerance limits are often less resistant to additional stressors, such as exposure to pollutants (Heugens, 2003). In previous experiments with fluctuating temperatures, we concluded that a water temperature of 12-14 • C was probably more optimal for G. fossarum (Schmidlin et al, 2014). The gammarids in the spring are exposed to 10 • C throughout the year and although the gammarids in the laboratory were also exposed to 10 • C, they were not subjected to additional stressors when compared to those in the spring.…”

“…The range of 0.4-6.4 mg Cu/L was chosen loosely on previously conducted LC 50 -tests (see Schmidlin et al, 2014). We started off with a ten times higher concentration than for the LC 50 -tests and then always doubled the concentrations in order to obtain a concentration range suitable for testing.…”

Miniature circulatory systems: A new exposure system for ecotoxicological effect assessments in riverine organisms

“…Finally, a toxicity test with G. roeseli was conducted to validate the suitability of miniature circulatory system for ecotoxicological investigations. Copper as Cu 2þ was used as the test substance, because data on copper toxicity to different Gammarus species with variable test durations already exist [35,36], allowing a qualitative assessment of the results obtained through the novel exposure system by comparing the LC50 values (concentration that causes 50% mortality).…”