Long term effects of total biomass harvesting on understory vegetation and tree stand in Norway spruce stands

Abstract

Northern Europe will be one of the locations where the renewable energy from forests could displace fossil fuels as a result of climate change: therefore, it will become more crucial to maintain renewable materials that also collect CO2. By taking tree biomass out of forest stands, we could create more renewable resources to use in practice, but this has certain negative effects on the forest ecology, including nitrogen leaching and vegetation degradation. The goal of the study is to investigate the effects of full biomass removal (FBR) in Norway spruce (Picea abies (L.) H. Karst.) forest stands and how this forest management affects vegetation regeneration, tree stock and carbon storage overall. The aforementioned structures were assessed at various forest ages. The central region of Latvia contains Norway spruce stands with all of the sample sites under study situated on drained peaty mineral soils and weakly aerated gleyic soils. As a result of the long-term evaluation, it was determined that the forest vegetation in FBR was similar to that in the same-age control stand (SAC) and that vegetation can successfully regenerate. The average tree height and DBH is lower in areas where stump removal and understory biomass was not carried out. Statistically significant (p<0.05) long-term influence of stump removal on the average height and diameter of Norway spruce can be identified in all parameters, except, tree height in Myrtillosa mel. forest type. Total biomass removal in long term has almost no significant effect on tree stand and vegetation regeneration.