The Influence of Wetland and Mineral Terrain Types on Snowmelt Runoff in the Subarctic

The water storage and runoff characteristics of wetland and mineral terrain types were assessed during the snowmelt period to determine their contribution to basin streamflow. Mineral terrain stored most of the meltwater produced because of its dry condition and depth to the water table, while fens were the most important source of runoff due to the impermeable frozen surface layer. Bog generated some runoff, but had considerable storage capacity compared to fens. The streamflow hydrograph during early melt was dominated by surface runoff from the fens, but basin lag increased daily as more of the basin contributed. The recession constant also increased daily as the thawing surface increased resistance to flow. While wetlands provided little ability to attenuate the spring flood, the occurrence of mineral terrains in the basin moderated the basin response.