%0 Research article
%T Export of suspended solids and dissolved elements from peatland areas after ditch network maintenance in south-central Finland
%A Nieminen, Mika
%A Ahti, Erkki
%A Koivusalo, Harri
%A Mattsson, Tuija
%A Sarkkola, Sakari
%A Laurén, Ari
%D 2010
%J Silva Fennica
%V 44
%N 1
%R doi:10.14214/sf.161
%U https://silvafennica.fi/article/161
%X In Finland nearly 6 million hectares of peatlands are drained for  forestry purposes. Ditch network maintenance in the drained peatlands,  i.e. cleaning old ditches or digging complementary ditches, deteriorates  surface water quality by increasing the export of dissolved elements  and suspended solids (SS). Effect of ditch network maintenance on the  export of SS, dissolved organic carbon (DOC), and dissolved nitrogen  (N), phosphorous (P), iron (Fe), aluminum (Al) and manganese (Mn) was  studied in nine pairs of treated and control (no maintenance) catchments  located in southern and central Finland. In this study we extended the  paired catchment approach by combining data from several catchments and  identifying the treatment effect on SS and element loads from the entire  dataset. Following the method of Laurén et al. (2009) we identified how  uncertainty in correlation between treatment and control catchments  during pre-treatment period is reflected in the estimated treatment  effect on SS and element loads. In the experiment, the export of SS  increased significantly for the four year study period following the  ditch network maintenance and Al export increased for one year. The  export of N, P and Fe was not significantly changed and DOC and Mn  export decreased after the ditch maintenance operation.