Effects of copper on growth, reproduction, survival and hemoglobin in Daphnia magna

• 1. The effects of additions of CuSO4 × 5H2O to final concentrations between 0.0004 and 105μg Cu l− on growth, reproduction, survival and haemoglobin content of Daphnia magna were studied in hard reconstituted water and compared to the response in the dilution water without addition of copper. Concentrations of copper are nominal values. 2. The 48-hr Spec50 (immobilization) for unfed neonates was 6.5 μg Cu l−1 and the 48-hr and 21-day lc50 for fed neonates were 18.5 and 1.4 μg Cu l−1, respectively. 3. Growth expressed as body length of juveniles after 7 days and adult females after 21 days was only reduced in survivors at the highest non-lethal concentration (6.6 μg Cu l−). 4. Reproduction was stimulated by low concentrations of copper. Optimal reproduction after 21 days was found between 0.001 and 0.1 μg Cu l−1. Higher concentrations were partially inhibitory (0.4 μgCu 1−1), stimulatory (0.8 and 1.6 μg Cu l−1) or completely inhibitory (3.2μg Cu l−1 and above). 5. The stimulatory peak around 1 μg Cu l−1 was accompanied by a reduced survival (above 0.4 μg Cu l−1). The Zero Equivalent Point (ZEP) for reproduction at non-reduced survival was 0.23 μg Cu l−1. This concentration should be “safe” for D. magna under prevailing conditions (reconstituted water with a hardness of 250 mg l−1 as CaCo3 and a synthetic diet based on fish food and baby gruel). 6. The haemoglobin content was affected by copper in a complex pattern which was not related to growth, reproduction or survival.

Ämnesord

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

NATURVETENSKAP  -- Geovetenskap och miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences (hsv//eng)

Nyckelord

Daphnia magna

copper

Cu

growth

reproduction

survival

hemoglobin

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)