Rapport nr 146: En helhetsbild av Lumparn-områdets status
EVELEENS MAARSE, F. K. J. (2017)
Åbo Akademi, Husö biologiska station
2017
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This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.
Julkaisun pysyvä osoite on
http://urn.fi/URN:ISBN:978-952-12-3494-1
http://urn.fi/URN:ISBN:978-952-12-3494-1
Tiivistelmä
During the summer of 2016, a study was performed to create a complete picture of the current situation and possible problems and solutions in the Lumparn area, as assigned by the Åland provincial government. This was done by gathering data and literature on Lumparn and its inlets from a range of sources such as the fisheries agency and the water agency, the government of Åland, and previous projects performed at Husö biological station. The gathered data included water parameters, catches from test fishing, vegetation cover and benthic fauna. The analyses showed that the water quality was worst in the inner part of the inlets, especially in Ämnäsviken and Kaldersfjärden, and gradually improved closer to the Lumparn basin. This was supported by the vegetation, benthic fauna and, to some extent,
the fish community data. All showed a difference in the community composition between the Lumparn basin and the inlets. The probable causes for this difference are eutrophication by an excess of nutrients and difference in exposure between the basin and the inlets. In order to determine the origin of the nutrients in the inlets, a more extensive study is required. Additionally, this study found established bristly stonewort (Chara horrida) in Mellanviken. Eelgrass (Zostera marina) occurred in the established sites, Östra Lumparn and Ranksholm, with increased coverage in Östra Lumparn compared to previous years, as well as at the two new locations Skarven and Röda kon. Previous studies have shown that the number of large individuals of zander (Sander lucioperca) has decreased in Lumparn during the 2000s.
the fish community data. All showed a difference in the community composition between the Lumparn basin and the inlets. The probable causes for this difference are eutrophication by an excess of nutrients and difference in exposure between the basin and the inlets. In order to determine the origin of the nutrients in the inlets, a more extensive study is required. Additionally, this study found established bristly stonewort (Chara horrida) in Mellanviken. Eelgrass (Zostera marina) occurred in the established sites, Östra Lumparn and Ranksholm, with increased coverage in Östra Lumparn compared to previous years, as well as at the two new locations Skarven and Röda kon. Previous studies have shown that the number of large individuals of zander (Sander lucioperca) has decreased in Lumparn during the 2000s.