Table 2. A future scenario for brownification, increasing water color due to increasing levels of DOC in surface water, in the River Helge å catchment based on four drivers of change.

Driver of change Mechanism for contribution to brownification Future contribution to brownification (as increase, stable, decrease) in the medium term (2050) Scale and type of intervention
Climate change (1) increase leaching of DOC through 100-year flows “much more often” and through increased soil temperatures. +

increase in coming decades

Global agreements and regional actions. Measures to slow down water flow in the upper parts of the watershed
Reversed acidification (2) increase leaching of DOC through decreasing deposition + to 0

increase in next decade then level out

-
Land cover change (3) increase stock of DOC through increased forest cover and increased coniferous forest cover + to -

stable/increase in coming decades than possibly decrease

Regional. Measures to slow down water flow in the upper parts of the watershed
Drainage of land (4) increase leaching of DOC through increased run-off,

increase stock of DOC through increased decomposition

+

stable/increase in coming decades

Regional. Measures to slow down water flow in the upper parts of the watershed