Päivi Picken

Suonpohjien turpeen alaisen mineraalimaan ominaisuudet eri geologisilla alueilla

Picken P. Suonpohjien turpeen alaisen mineraalimaan ominaisuudet eri geologisilla alueilla.

English title: The characteristics of mineral subsoils of Finnish cut-away peatlands related to different geological areas

Tiivistelmä

In Finland, the whole peat layer of a peat production area is used due to the value of the basal peat as energy peat. In this situation the properties of the mineral subsoil below the peat layer are significant when choosing the form of after-use. The geochemical provinces are based on the chemical features of the fine material in till, related to differences found in the bedrock, defined by Geological Survey of Finland. The study of peat production areas (1998-1999, covering 9800 ha) shows that the characteristics of the provinces affects the subsoil sediments. In Lake Ladoga–Bothnian Bay zone subsoils were rich in sulphur and iron. The amount of water soluble sulphur was 3-6 times higher than that in the Granitoid area of Central Finland and the Archaean gneiss areas (calculated as mg kg-1). Below the highest shoreline of the ancient Litorina Sea the average content of the water soluble sulphur in subsoil sediments was ca. seven fold compared to the content found above the highest shoreline, (calculated as mg kg-1). There was also a difference in soil acidity between these areas. Nutrient content varied between sediments, which have the same fine material percentage. In the Lake Ladoga–Bothnian Bay geological zone and in the zones of Svecocarelian schists and gneisses, natural nutrient levels are high when compared to the Granitoid areas.

Avainsanat
cut-away peatlands; after-use; mineral subsoil; geochemical province; Litorina zone

Vastaanotettu 31.10.2017 Julkaistu 1.1.2005

Katselukerrat 1214

Saatavilla http://suo.fi/article/9838 | Lataa PDF

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