Abstract
Abstract The small fjord Lakselvvatn in North Norway, with a mean water-level 1 m above mean sea-level, was sampled 4 times in 1982–83. A layer of fresh water, normally 2 m, but up to 11 m thick, was found over brackish water of salinity increasing to 27 ‰. A halocline was always present somewhere between 7 and 13 m. Oxygen decreased with depth to zero at 30 m; this is judged to be a fairly permanent situation. A fresh-water fauna similar to that of nearby lakes was present in the littoral zone, and fresh-water planktonic crustaceans occurred in low numbers, generally above 2 m depth. Planktonic crustaceans of marine character were almost exclusively confined to polyhaline water, but Eurytemora affinis tolerated even fresh water. Twenty two taxa of macrobenthos showed a distinct vertical zonation above 30 m depth, strongly influenced by the salinity and oxygen gradients, and involving special vertical patterns of diversity and biomass. The established tolerance limits towards short exposures to fresh wate...
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call