In:
International Review of Hydrobiology, Wiley, Vol. 83, No. 5-6 ( 1998-01), p. 479-499
Abstract:
The Nordrügenschen Bodden waters are a shallow coastal inlet of the Southern Baltic Sea consisting of individual basins, some of which are joined only via small connections. The Bodden are characterized by pronounced horizontal gradients in hydrographical, chemical and biological parameters. Whereas concentrations of inorganic nutrients increase, salinity decreases with increasing distance from the connection to the Baltic Sea. Between 1960 and 1989 long‐term variations of salinity, inorganic nutrients (ammonium, nitrate, phosphate), Secchi disk visibility, and planktonic primary production were monitored at 6 locations throughout the Bodden. The gradients were most pronounced during the first period of observation (1960–1963). Between 1960 and 1985 concentrations of inorganic nutrients in the adjacent Arkona Sea increased up to values several times higher than the previous concentrations. This increased nutrient load in the Baltic Sea was reflected by higher nutrient concentrations and higher primary production in the outer and central parts of the Nordrügenschen Bodden. Between 1963 and 1965 the shipping channel between the outer (Libben) and the inner part (Großer Jasmunder Bodden) of the Bodden chain was dredged. This led to an improvement of water exchange between the Baltic Sea and the Bodden, resulting in a significant reduction of the gradients of chemical and biological parameters. Whereas salinity and Secchi disk visibility increased, inorganic nutrients, and primary production decreased. This was most obvious in the inner parts of the Bodden where the water quality was improved. The trophic status of the Kleiner Jasmunder Bodden is still worrying. This Bodden represents the innermost part of the Nordrügenschen Bodden connected with the Großer Jasmunder Bodden only via a small flood gate. Unless the water exchange is drastically improved, the Kleiner Jasmunder Bodden will retain its hypertrophic status in the longer term. The future development of the trophic status of the Bodden is discussed.
Type of Medium:
Online Resource
ISSN:
1434-2944
,
1522-2632
DOI:
10.1002/iroh.v83:5/6
DOI:
10.1002/iroh.19980830516
Language:
English
Publisher:
Wiley
Publication Date:
1998
detail.hit.zdb_id:
2006634-X
detail.hit.zdb_id:
1420232-3
SSG:
12
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