Abstract

Early developmental stages of Atlantic salmon and brown trout were exposed in situ to different water qualities in a river affected by acidification and wetland liming. Mortality, hatching frequency, histopathology and whole-body electrolytes were investigated. The hatching frequency was low in acidic aluminum-rich water, and the whole-body concentration of potassium and sodium decreased as early as after 13 days of exposure. Prolonged exposure caused 100% mortality of Atlantic salmon at this locality. A histochemical study disclosed Al precipitates in the gills of fish exposed to the acidic brooks. The precipitates were associated with the apical plasma membrane, and were also occasionally present intracellularly. The latter observation was confirmed by ultrastructural studies in which electron-dense precipitates were found in the cytoplasm of chloride cells. Chorions from non- or incompletely hatched eggs exposed in the acidic part of Torskabacken were compared with the chorions from fry hatched in the limed part of the same brook. Eggs which failed to hatch had an intact inner chorion surface. Atlantic salmon were more sensitive to acidic Al-rich waters than brown trout, both at hatching and as yolksac fry. Wetland liming effectively protected salmonid fish reproducing in such waters.

Published in

AMBIO: A Journal of the Human Environment
1993, Volume: 22, number: 4, pages: 213-218
Publisher: ROYAL SWEDISH ACAD SCIENCES

SLU Authors

• Norrgren, Leif

  • Department of Pathology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Ecology


Permanent link to this page (URI)

https://res.slu.se/id/publ/40638