RESULTS & DISCUSSION
NITROGEN REMOVAL (I-II)
3.1.1 DENITRIFICATION IN AGRICULTURAL WETLAND (I)
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Figure 6. Relationship between denitrification rate (mg N m-2 d-1) and the sediment surface temperature in the agricultural wetland littoral (modified from the study I). Denitrification rates are added with 1 mg N m−2 d−1 to remove the zero.
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Figure 7. Measured (black columns) and estimated (grey columns) denitrification rates in Koiransuolenoja wetland littoral, modified from the study I.
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Table 3. Mean denitrification and anammox rates (I,II) and results from other studies conducted under low air and water temperatures, water NOx--N concentrations also shown. Standard deviation (±) and
minimum/maximum between brackets. *=measured with static chamber technique, ** air temperature,
***=measured from the wetland inlet and outlet.
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Figure 8. The variation of the C:N ratio in the wastewater treatment plant discharge into the wetland as well as in the wetland outlet.
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