Summary: | The study examined the goal fulfillment in edge zones along rivers and lakes in precommercial thinning stands based on national targets which is the basis for Swedish forestry. Pre-commercial thinning has a major impact on the future forest, as it determines how the tree species distribution will turn out. The study was conducted as a field study in February 2018 based on 30 precommercial thinning sites, aged 5–15 years, in connection to rivers and / or lakes. Of these, 25 rivers and five lakes were surveyed. 22 of the surveyed stands were privately owned and 8 were company-owned forests. The edge zones had between 0–100% shadowing of the water surface. Few sites with soil damage were detected and also a varying amount of tree species and deadwood. The most common deadwood was standing and lying dead wood with a diameter of 10 cm for both company and privately-owned forests. The percentage of number of stems per ha of deciduous trees in the edge zones was 52%, Norway spruce 41% and Scots pine 7% respectively. Within the edge zones, the sample areas closest to rivers and lakes had 55% of number of stems per ha deciduous trees, 40% spruce and 6% pine. In the sample areas closest to the stand, the number of deciduous trees was 48%, spruce 44% and pine 9%. Company-owned forests had more spruce (59%) along the waterfront compared to privately owned forests, who had a significantly higher proportion of deciduous trees (61%). By actively working with the composition of the edge zones, creating deadwood, saving trees for shadow and by thinning dense areas, particularly spruce-dominated, increased biodiversity can be achieved. Dense, spruce-dominated areas are those areas where the goal fulfillment is insufficient in many places.
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