Selection of real-life analogues for future lakes and mires at a repository site

Abstract

Abstract. In Finland, Olkiluoto Island on the western coast has been selected as a repository site for spent nuclear fuel. Due to the shallow sea areas around the island, the postglacial land uplift is going to change the landscape within the next millennia. For instance, new lakes and mires will develop on the present offshore areas. Concerning radionuclide transport models, the properties of the future ecosystems surrounding Olkiluoto Island can be forecast based on the properties of present lakes and mires. Due to the lack of site-specific data, lakes and mires of various successional stages were selected within a larger geographical area as analogues of the future ones. Here we present an example of a systematic process for selection of appropriate analogue sites.

Concentration ratios to aquatic plants at and near Olkiluoto repository site

“…6.5 m). Till and rocky forests and clay fields cover most of its 5.0-km 2 catchment area [5]. The lake has been ICRER 2011 chosen as an analogue of a small headwater lake.…”

“…3.2 m). Its catchment area, 65 km 2 , is covered by till and rocky forests and mires [5]. In Posiva's biosphere assessment the lake has been chosen to represent an overgrowing, larger lake.…”

“…1) with a mean depth of less than 10.0 m and the deepest depressions to 15.5 [4]. Two rivers, with a combined mean discharge of 12.0 m 3 /s and a catchment area of 1700 km 2 , have their mouths in eastern part of the area [5]. The catchment area is covered by clays field, till and rocky forest and mires.…”

On real and abstracted geometries of boreal forest plants

“…Three of the study sites located at Olkiluoto (Table 1, see also [6]). FIP4 is an intensively studied forest monitoring plot.…”

“…Lastensuo mire (area 440 ha, elevation 44-48 m a.s.l.) belongs to the sites chosen as analogues to the mires expected to form with post-glacial land uplift in Olkiluoto (see [7], and the paper by Haapanen et al to this conference) and is located relatively near to Olkiluoto Island, in Eurajoki municipality. The centre of this raised bog is almost treeless, Scots pine being the dominant tree species in forested areas of the mire.…”