Under Biological Invasion: Impacts of Litter Decomposition Mediated by Invasive Plant Species on Soil Nutrients and Functional Growth Traits of both Invasive and Native Plant Species

An invasive plant, Solidago canadensis is quickly encroaching across Eastern China and has become a crucial concern in the alteration of native ecosystem structure and function. However, the impact on invaded soil from S. canadensis litter is still under consideration. This study evaluated the effects of different levels of litter mass (Control: L0, 5 g: L5, 10 g: L10, 15 g: L15, and 20 g: L20) of invasive S. canadensis on the functional traits of two congeneric plant species (S. canadensis and S. decurrens), as well as resulting variations in soil nutrient levels. Our results indicated that shoot and root length, fresh and dry biomass, leaf chlorophyll and leaf nitrogen were significantly higher at L15 compared to the other treatments in the experiment. Additionally, in the L20 treatment all traits were decreased drastically, although these were higher than the control treatment, i.e. L0. Soil nutrients increased as the level of litter mass was raised in the soil. Furthermore, our study showed that high litter mass from S. canadensis can adversely impact the functional traits of both plant species. Further studies are required to assess the allelopathic effect of litter mass, as well as biological and physicochemical properties of field soil where high quantities of the invasive plant litter are found.