A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Development of Lake Vesijärvi through four decades of remediation efforts
Tekijät: Kalevi Salonen, Jouko Sarvala, Jukka Horppila, Juha Keto, Ismo Malin, Tommi Malinen, Juha Niemistö, Jukka Ruuhijärvi
Kustantaja: SPRINGER
Julkaisuvuosi: 2020
Journal: Hydrobiologia
Tietokannassa oleva lehden nimi: HYDROBIOLOGIA
Lehden akronyymi: HYDROBIOLOGIA
Sivujen määrä: 19
ISSN: 0018-8158
eISSN: 1573-5117
DOI: https://doi.org/10.1007/s10750-020-04338-3
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/48761741
The diversion of sewage inputs in the mid-1970s led to an order of magnitude reduction in nutrient loading to Lake Vesijarvi, southern Finland. After the diversion, nutrient concentrations declined, consistent with a simple dilution model, and by the mid-1990s the chlorophyll concentration was reduced by 80%. The favourable development was supported by a 5-year mass removal of planktivorous and benthivorous fish and the stocking of predatory pikeperch (Sander lucioperca (L.)), although the exact mechanisms behind their effects remain obscure. Starting in 2010, oxygen-rich water from the top of the water column was pumped to the deepest parts of the lake, resulting in high deepwater oxygen concentration in winter. In summer, hypoxic or even anoxic conditions could not be avoided, but the duration of the anoxic period was markedly shortened. Because nitrate was never depleted, leaching of total nitrogen from the sediment was reduced and the same was also true for total phosphorus, but only in winter. The oxygenation stabilized deepwater nutrient concentrations to a low level, but this was not reflected in the epilimnetic total nutrient concentration or in a further decrease in the chlorophyll concentration.
Ladattava julkaisu This is an electronic reprint of the original article. |