Conservation Management in Riparian Zones : a follow up of the Nissan water management agreement

Abstract: Forest management in riparian zones has consequences for the aquatic ecosystem. In 2015, Sveaskog signed a water management agreement for the river Nissan with the purpose of promoting broadleaves and improving the riparian ecosystems inside the agreement area. This study followed up the conservation cuttings made in older stands in the agreement area through a field inventory. To evaluate the need of future management, an Heureka StandWise analysis based on different field trials of mixed forests was made. The inventory showed that broadleaves had been favoured in the conservation cuttings by removing conifers where there was established broadleaves, mainly along the water edge, where the highest density of broadleaved stems where found. Where there were less broadleaves, inside the buffer zone, larger gaps had been cut to provide opportunity for natural regeneration through reduced stem densities and larger canopy openness. There were, however, field vegetation that might compete with potential seedlings. The StandWise analysis showed that active management is required to favour the broadleaves in the future. If monocultures were established after the conservation cuttings, future management had little effect on species composition. Future management should be adapted to each stands species distribution and site conditions vary due to the size and distribution of the agreement area.