Effect of mixing herbaceous litter with tree litters on decomposition and N release in boreal plantations

Abstract

Background and Aims Abandoned lands are increasingly used to establish fast-growing tree plantations, and are often rapidly colonized by a high density of herbaceous undergrowth. These weeds are generally removed since they compete with trees for resources, in particular soil nutrients. However, mixing herbaceous litter with the litter of planted trees could also stimulate the activity of decomposers and associated nutrient release due to an increase of litter quality (lower C:N ratio), plant diversity (more diverse litter traits) and water holding capacity. The objective was to determine the impact of herbaceous litter on the litter decomposition process of white spruce and hybrid poplar litters alone or in mixtures.