Ekologiska restaureringsåtgärders påverkan på unga trädplantor : bränning och luckhuggnings effekt på unga trädplantor

Abstract: Biodiversity is fundamental for a stable and functional ecosystem. However, studies have shown that biodiversity in Sweden is slowly declining due to modern forestry. This needs to be changed and ecological restoration can prevent further biodiversity loss. The purpose of this study was therefor to increase the knowledge of how restauration methods in the form of burning and gap cutting affects young tree plants. In this report, data from 18 different stands was compared and analysed. The three measures that where compared was: burning, gap-cutting and control plots. Each measure was done on six stands each. The study examines change in mean height, number of trees per hectare and tree species compositions on young tree plants where either one of the two ecological restauration methods had taken place. In comparing of the tree species composition, Simpsons Diversity Index (SDI) and Effective Number of Species (ENS) was used to measure biodiversity. The indexes showed a decrease in tree species composition in connection to gap cutting and burning. The indexes take species evenness in consideration when comparing. A rise in number of plants was observed in the ecologically restored stands when compared to the control stands. An increase in broad leaf trees was observed. Broadleaf trees establish well after a disturbance and could be the reason to the increased number of plants. When analysing the mean height of young tree plants no significant difference was observed. This result can however be seen as somewhat misleading. This is due to two things, the first is the fact that only trees between 0-1.5 m was included in the measuring. The second is the fact that the burned stands had to start over and establish new tree plants whilst the other two already had established plants.