Impact of acid sulfate soil catchments on water quality in a lake in western Finland; trends and total metal load

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)

Interna författare/redaktörer

Publikationens författare: Janne Toivonen, Sören Fröjdö, Peter Österholm
Förläggare: Boreal Environment Research Publishing Board.
Förlagsort: Helsingfors
Publiceringsår: 2019
Tidskrift: Boreal Environment Research
Tidskriftsakronym: BOREAL ENV. RES.
Volym: 24
Artikelns första sida, sidnummer: 79
Artikelns sista sida, sidnummer: 99
eISSN: 1797-2469


Acid sulfate soils occur worldwide and can cause serious ecological damage by releasing
acidity and toxic metals into watercourses. This study focused on short- and long-term
changes to the water quality of a lake in western Finland. Here, a decline in water quality
took place in the late 1960s. Since then, events concerning poor water quality have frequently occurred. The annual load of some potentially toxic metals varied from hundreds
of kilograms to thousands of tons, depending on the metal. The proportion of low-order
streams draining the nearest field to the lake is only 7% of the catchment area, while the
share of the total metal load was estimated to be over 30%. This points to the importance
of monitoring small coastal catchments. High runoff conditions were proven to be more
important in terms of water quality than occasional summer droughts. During the past
decade, acidic conditions have become more prolonged in the autumn, which is in line with
a predicted scenario relating to climate change.


Senast uppdaterad 2020-09-07 vid 04:04