ISSN:
1432-0703
Source:
Springer Online Journal Archives 1860-2000
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Medicine
Notes:
Abstract A field survey revealed that Al, SO4, H+, and Zn were significantly higher in 40 ponds lacking successful breeding of the Jefferson salamander, A. jeffersonianum, whereas alkalinity, Cu, DOC, K, Mg, Na, and NO3 were significantly higher in 10 ponds that supported successful breeding. In a second smaller set of ponds used for transplant studies, Al, conductivity, H+, and SiO2 were significantly higher in five ponds lacking reproduction of A. jeffersonianum; alkalinity, Ca, and K were significantly higher in three ponds with successful reproduction. Survival and hatching success were significantly greater for egg masses transplanted into ponds supporting viable Jefferson salamander populations than into those that did not. Survival and hatching success were greater at 15°C than at 10°C. Low pH slowed developmental rate, consequently increasing the time until hatching. Low pH decreased hatching success of the embryos at 10 and 15°C. Copper was acutely toxic to embryos at pH 4.50 (96 h LC50=315 μg/L); chronic exposure levels in the field were much lower (approximately 0.01 times). Since successful ponds actually contained more Cu than unsuccessful ones, Cu does not appear to be toxic in the field. Aluminum ameliorated the acute 96 h toxicity of pH 4.50; at [Al]'s between 250 and 500 μg/L mortality at pH 4.50 was greatly reduced. This effect of Al occurred at concentrations comparable to those found in the field. Lead and zinc, at concentrations up to 2,000 μg/L, had no apparent effects on the developing embryos of A. jeffersonianum. Aluminum, Pb, and Zn did not afect developmental rate, as did low pH and Cu. Based on these findings, low pH and its interaction with Al are likely to be major factors responsible for the success or failure of the Jefferson salamander in breeding ponds in Pennsylvania. Further investigation is needed into interations among pH, metals, dissolved organics, and non-toxic cations to further clarify the mechanisms of toxicity of the complex mixture of which pond water consists.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00213167
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