TY - JOUR
T1 - Restoration of nutrient-rich forestry-drained peatlands poses a risk for high exports of dissolved organic carbon, nitrogen, and phosphorus
AU - Koskinen, Markku
AU - Tahvanainen, Teemu
AU - Sarkkola, Sakari
AU - Menberu, Meseret Walle
AU - Laurén, Ari
AU - Sallantaus, Tapani
AU - Marttila, Hannu
AU - Ronkanen, Anna Kaisa
AU - Parviainen, Miia
AU - Tolvanen, Anne
AU - Koivusalo, Harri
AU - Nieminen, Mika
PY - 2017/5
Y1 - 2017/5
N2 - Restoration impact of forestry-drained peatlands on runoff water quality and dissolved organic carbon (DOC) and nutrient export was studied. Eight catchments were included: three mesotrophic (one undrained control, two treatments), two ombrotrophic (one drained control, one treatment) and three oligotrophic catchments (one undrained control, two treatments). Three calibration years and four post-restoration years were included in the data from seven catchments, for which runoff was recorded. For one mesotrophic treatment catchment only one year of pre-restoration and two years of post-restoration water quality data is reported. Restoration was done by filling in and damming the ditches. Water samples were collected monthly-biweekly during the snow-free period; runoff was recorded continuously during the same period. Water quality was estimated for winter using ratios derived from external data. Runoff for non-recorded periods were estimated using the FEMMA model.A high impact on DOC, nitrogen (N) and phosphorus (P) was observed in the mesotrophic catchments, and mostly no significant impact in the nutrient-poor catchments. The DOC load from one catchment exceeded 1000kg (restored-ha) -1 in the first year; increase of DOC concentration from 50 to 250mgl -1 was observed in the other mesotrophic treatment catchment. Impact on total nitrogen export of over 30kg (restored-ha) -1 was observed in one fertile catchment during the first year. An impact of over 5kg (restored-ha) -1 on ammonium export was observed in one year in the mesotrophic catchment. Impact on P export from the mesotrophic catchment was nearly 5kg P (restored-ha) -1 in the first year.The results imply that restoration of nutrient-rich forestry-drained peatlands poses significant risk for at least short term elevated loads degrading the water quality in receiving water bodies. Restoration of nutrient-poor peatlands poses a minor risk in comparison. Research is needed regarding the factors behind these risks and how to mitigate them.
AB - Restoration impact of forestry-drained peatlands on runoff water quality and dissolved organic carbon (DOC) and nutrient export was studied. Eight catchments were included: three mesotrophic (one undrained control, two treatments), two ombrotrophic (one drained control, one treatment) and three oligotrophic catchments (one undrained control, two treatments). Three calibration years and four post-restoration years were included in the data from seven catchments, for which runoff was recorded. For one mesotrophic treatment catchment only one year of pre-restoration and two years of post-restoration water quality data is reported. Restoration was done by filling in and damming the ditches. Water samples were collected monthly-biweekly during the snow-free period; runoff was recorded continuously during the same period. Water quality was estimated for winter using ratios derived from external data. Runoff for non-recorded periods were estimated using the FEMMA model.A high impact on DOC, nitrogen (N) and phosphorus (P) was observed in the mesotrophic catchments, and mostly no significant impact in the nutrient-poor catchments. The DOC load from one catchment exceeded 1000kg (restored-ha) -1 in the first year; increase of DOC concentration from 50 to 250mgl -1 was observed in the other mesotrophic treatment catchment. Impact on total nitrogen export of over 30kg (restored-ha) -1 was observed in one fertile catchment during the first year. An impact of over 5kg (restored-ha) -1 on ammonium export was observed in one year in the mesotrophic catchment. Impact on P export from the mesotrophic catchment was nearly 5kg P (restored-ha) -1 in the first year.The results imply that restoration of nutrient-rich forestry-drained peatlands poses significant risk for at least short term elevated loads degrading the water quality in receiving water bodies. Restoration of nutrient-poor peatlands poses a minor risk in comparison. Research is needed regarding the factors behind these risks and how to mitigate them.
KW - DOC
KW - Leaching
KW - Nutrients
KW - Peatland forests
KW - Restoration
UR - https://www.scopus.com/pages/publications/85012931321
U2 - 10.1016/j.scitotenv.2017.02.065
DO - 10.1016/j.scitotenv.2017.02.065
M3 - Article
AN - SCOPUS:85012931321
SN - 0048-9697
VL - 586
SP - 858
EP - 869
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -