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pro vyhledávání: '"Harri Helminen"'
Autor:
Harri Helminen, Arto Inkala
Publikováno v:
Journal of Marine Science and Engineering, Vol 12, Iss 8, p 1252 (2024)
The Baltic Sea is currently classified as ‘affected by eutrophication’. In this study, water exchanges and net phosphorus flows in the Archipelago Sea and through the Åland Sea from the Baltic proper was estimated with the aid of a 3-D hydrodyna
Externí odkaz:
https://doaj.org/article/771a16c4c9514a0c8de6a24e5f0d0a05
Autor:
Harri Helminen, Jouko Sarvala
Publikováno v:
Annales Zoologici Fennici. 58
Long-term monitoring of the planktivorous vendace (Coregonus albula) in Pyhajarvi, a lake in SW Finland, revealed periods characterised by different types of population regulation. In 1971–1989, the vendace stock was strong and exhibited a two-year
Autor:
Jouko Sarvala, Harri Helminen
Publikováno v:
Annales Zoologici Fennici. 58
Catches of vendace (Coregonus albula) from Pyhajarvi, a boreal lake in SW Finland, were exceptionally high for decades. Gradually, however, eutrophication and climate warming significantly changed the lake environment. From the 1970s to the 2010s, to
Publikováno v:
Fisheries Research. 230:105664
Vendace (Coregonus albula) is a small and rapidly reproducing planktivorous coregonid species that is known to endure very high fishing pressure. Catch levels of 10–25 kg ha−1 a−1 have been sustained for extended periods in several Finnish lake
Autor:
Harri Helminen, Marjo Tarvainen, Amaury Lendasse, Jouko Sarvala, Anne-Mari Ventelä, Teija Kirkkala
Publikováno v:
Hydrobiologia. 660:49-58
Sakylan Pyhajarvi (SW Finland) is an example of a large and shallow lake suffering from eutrophication. During the last 20 years, the quality and general usability of water in Pyhajarvi have shown considerable variation driven by both a variety of hu
Publikováno v:
Lake and Reservoir Management. 23:428-438
Pyhajarvi, located in the centre of an intensive agricultural area in southwest Finland, is an example of a lake suffering from eutrophication. The lake has been intensively studied for decades and was the object of comprehensive restoration activiti
Autor:
Lassi Suominen, Harri Helminen, Jaana Sipura, Janne Suomela, Annika Lagus, Kaarina Sivonen, Jaana M. Lehtimäki
Publikováno v:
University of Helsinki
An experiment was carried out in brackish seawater mesocosms to investigate the impacts of different N:P ratios and frequency of nutrient supply on phytoplankton and zooplankton communities in the Archipelago Sea, part of the northern Baltic Sea. The
Publikováno v:
Hydrobiologia. 579:351-368
A three-week mesocosm experiment was conducted in order to study the effects of bottom sediment and nutrient enrichment on phytoplankton and zooplankton community structure in the Archipelago Sea, northern Baltic Sea. The transparent polyethylene enc
Publikováno v:
Journal of Plankton Research. 27:1261-1272
Effects of nutrient enrichment on the biomass and community composition of heterotrophic bacteria and picocyanobacteria were studied in large (42 m 3 ) mesocosms in the brackish-water Archipelago Sea (Baltic Sea) in late summer 2000 using cell counts
Publikováno v:
Journal of Experimental Marine Biology and Ecology. 322:39-52
The impact of nutrient enrichment on the phytoplankton community structure, and particularly cyanobacteria, was studied in a 3-week mesocosm experiment conducted in August 2001 in the Archipelago Sea, a part of the northern Baltic Sea. The factorial