scholarly journals Changes in 22Na influx and outflux in Daphnia magna (Straus) as a function of elevated Al concentrations in soft water at low pH

1985 ◽  
Vol 82 (21) ◽  
pp. 7345-7349 ◽  
Author(s):  
M. Havas ◽  
G. E. Likens
Keyword(s):  
Daphnia Magna ◽  
Low Ph ◽  
Soft Water

Effect of low pH on sodium regulation in two species of Daphnia

1984 ◽  
Vol 62 (10) ◽  
pp. 1965-1970 ◽  
Author(s):  
Magda Havas ◽  
Thomas C. Hutchinson ◽  
Gene E. Likens
Keyword(s):  
Daphnia Magna ◽  
Hard Water ◽  
Low Ph ◽  
Soft Water ◽  
Sodium Influx ◽  
Daphnia Middendorffiana ◽  
Sodium Loss ◽  
Sodium Regulation

The effect of low pH on sodium-22 influx and outflux of Daphnia magna and Daphnia middendorffiana was assessed. Experiments were conducted in both hard and soft water with experimental pHs ranging from 3.5 to 8.0. In hard water, at and below pH 4.0, there was a net loss of sodium from both species. The rate of sodium loss (outflux) increased significantly, while the rate of uptake (influx) remained constant at pH 4.0 compared with the reference pH 8.0. Only at extremely low pH (pH 3.5) was sodium influx inhibited in hard water. In soft water, D. magna responded quite differently. Sodium influx was inhibited by 23% at pH 5.0 and by 69% at pH 4.5 compared with the control (pH 6.5). Sodium outflux was stimulated to 125% of the control at pH 4.5. The net loss of sodium in soft water was due to both an increase in sodium outflux and a decrease in sodium influx, while in hard water the effect was primarily on sodium outflux. Daphnia magna and D. middendorffiana have problems with sodium regulation below pH 5.5 in soft water and below pH 4.5 in hard water, which indicates that they are considerably more sensitive to low pH in soft water than in hard water.

Aluminum Bioaccumulation and Toxicity to Daphnia magna in Soft Water at Low pH

1985 ◽  
Vol 42 (11) ◽  
pp. 1741-1748 ◽  
Author(s):  
Magda Havas
Keyword(s):  
Daphnia Magna ◽  
Negative Correlation ◽  
Laboratory Experiments ◽  
Low Ph ◽  
Al Toxicity ◽  
Soft Water ◽  
Consistent Pattern ◽  
Additional Source ◽  
Zooplanktivorous Fish ◽  
Al Content

Aluminum may be either harmful or beneficial to Daphnia magna (Straus) depending on pH and on the Al concentration in the water. My results are based on laboratory experiments conducted at various concentrations of total Al (0.02–1.02 mg/L) in soft water (2.5 and 12.5 mg Ca/L) adjusted from pH 6.5 to 4.5. Maximum Al toxicity and maximum Al bioaccumulation were observed at pH 6.5 (at and above 0.32 mg total Al/L). At lower pHs ([Formula: see text]), H+ was toxic to D. magna. Aluminum (1.02 mg/L) temporarily ameliorated H+ toxicity at pH 4.5. Calcium reduced H+ toxicity at pH 5.0 and Al toxicity at pH 6.5. Mortality in the presence of Al and also at low pH was associated with a net loss of Na and Cl from the daphnids. The Ca content of the daphnids was highly variable and showed no consistent pattern apart from a negative correlation with the Al content of the daphnids at pH 5.0 and 5.5. The 24-h bioconcentration ratio for Al was 10 000 at pH 6.5,4000 at pH 5.0, and negligible at pH 4.5. The rapid uptake of Al, particularly at circumneutral pHs, may be an additional source of Al for zooplanktivorous fish and other predators.

Can natural levels of Al influence Cu speciation and toxicity to Daphnia magna in a Swedish soft water lake?

Chemosphere ◽  
2015 ◽  
Vol 138 ◽  
pp. 205-210 ◽  
Author(s):  
S. Hoppe ◽  
J.-P. Gustafsson ◽  
H. Borg ◽  
M. Breitholtz
Keyword(s):  
Daphnia Magna ◽  
Soft Water ◽  
Water Lake ◽  
Soft Water Lake

Effects of Acid Water and Aluminum on Parr–Smolt Transformation and Seawater Tolerance in Atlantic Salmon, Salmo salar

1993 ◽  
Vol 50 (9) ◽  
pp. 1816-1827 ◽  
Author(s):  
Magne Staurnes ◽  
Per Blix ◽  
Ola B. Reite
Keyword(s):  
Carbonic Anhydrase ◽  
Atlantic Salmon ◽  
Atpase Activity ◽  
Salmo Salar ◽  
Carbonic Anhydrase Activity ◽  
Low Ph ◽  
Soft Water ◽  
Control Fish ◽  
Exposed Fish ◽  
Seawater Tolerance

Smolting Atlantic salmon, Salmo salar, were kept from 11 April to 24 May in soft water of pH 5 or in soft water of pH 5 and 50 μg aluminum (Al)∙L−1. Control fish were kept in soft water of pH 6.3–6.5. Water temperature was 8–14 °C. In mid-May, some of the control smolts were transferred to the test conditions for 8 d. Exposure to acid water resulted in osmoregulatory failure and high mortality rate. Al strongly enhanced toxicity. Sensitivity to low pH or low pH/Al exposure greatly increased when fish had developed to seawater tolerant smolts. In control and acid-exposed fish, gill carbonic anhydrase activity remained unchanged throughout the experiment whereas in Al-exposed fish, carbonic anhydrase activity decreased. Gill Na+K+-ATPase activity in control fish peaked in mid-May simulanteously with development of seawater tolerance. Fish from both acid-exposed groups had low seawater tolerance. Na+,K+-ATPase activity declined to 60% of start value in acid-exposed fish and to parr level in Al-exposed fish. Hypoosmoregulatory ability was linearly correlated with gill Na+K+-ATPase activity. Reduction in plasma Na+ concentration in acid-exposed fish was linearly correlated with the reduction in gill Na+,K+-ATPase activity.

scholarly journals Responses of an Amazonian Teleost, the Tambaqui (Colossoma macropomum), to Low pH in Extremely Soft Water

1998 ◽  
Vol 71 (6) ◽  
pp. 658-670 ◽  
Author(s):  
Chris M. Wood ◽  
Rod W. Wilson ◽  
Richard J. Gonzalez ◽  
Marjorie L. Patrick ◽  
Harold L. Bergman ◽  
...  
Keyword(s):  
Low Ph ◽  
Soft Water ◽  
Colossoma Macropomum

The Influence of Calcium on the Physiological Responses of the Rainbow Trout, Salmo Gairdneri, to Low Environmental pH

1980 ◽  
Vol 88 (1) ◽  
pp. 109-132
Author(s):  
D. G. McDONALD ◽  
H. HŌBE ◽  
C. M. WOOD
Keyword(s):  
Rainbow Trout ◽  
Calcium Concentration ◽  
Physiological Responses ◽  
Hard Water ◽  
Low Ph ◽  
Soft Water ◽  
Salmo Gairdneri ◽  
Minor Depression ◽  
Regulatory Failure ◽  
A Minor

The physiological responses of 1- to 2-year-old rainbow trout to low pH are dependent on the environmental calcium concentration. Trout, maintained for 5 days in moderately hard water ([Ca2+] = 1·6–2·7 m-equiv/1) at a mean pH of 4·3, developed a major blood acidosis but exhibited only a minor depression in plasma ion levels. In acidified soft water ([Ca2+] = 0·3 m-equiv/1), only a minor acidosis occurred, but plasma ion levels fell and there were substantially greater mortalities. Lethal bioassays performed on fingerling trout over a range of pH levels (3·0–4·8) revealed an important influence of external [Ca2+] on resistance to acid exposure. Terminal physiological measurements on adult fish succumbing to low pH in soft water indicate the singular importance of iono-regulatory failure as the toxic mechanism of action under these circumstances.

Hatching Success of Mayfly Eggs at Low pH

1988 ◽  
Vol 45 (9) ◽  
pp. 1649-1652 ◽  
Author(s):  
Locke Rowe ◽  
Jeffrey Hudson ◽  
Michael Berrill
Keyword(s):  
Hatching Success ◽  
Low Ph ◽  
Soft Water ◽  
The Other ◽  
Hatching Rate ◽  
Field Surveys ◽  
Acid Sensitivity ◽  
Significant Mortality

Eggs of the mayflies Leptophlebia cupida, Habrophlebia vibrans, Stenonema femoratum, and Baetis flavistriga were reared in soft water at several pH levels (4.0, 4.5, 5.0, and 6.5) in the laboratory. The proportion of eggs undergoing eclosion did not vary with pH. However, in B. flavistriga, significant mortality of nymphs occurred before the hatch was complete at pH 4.0 (91%) and 4.5 (12%). Hatching rate of H. vibrans was significantly retarded at pH 4.0, 4.5, and especially at pH 5.0, but was unaffected in the other three species. The effects of elevated [H+] on these species are in agreement with their relative acid sensitivity inferred from field surveys.

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