Plant responses to nitrogen fertilization differ between post-mined and original peatlands

摘要: Nitrogen addition experiments were conducted in three plant communities a post-mined peatland and on the surrounding original Sphagnum bog northern Japan to compare effects of nitrogenous fertilization among communities. Gradients added nitrogen prepared by adding 1 m × plots at rates 0–36 g/m2/yr. These different levels applied four sites representing vegetation development chronosequence: bare ground (BG), Rhynchospora alba sedgeland (RA), Moliniopsis japonica grassland (MJ) (SS). Vegetation was monitored each plot for years, groundwater level concentration peat-pore water plot. The increased with increasing BG, but constantly low vegetated sites, suggesting occurrence nutrient uptake plants. Species richness decreased as result SS site, where cover high. aboveground biomass two common grasses M. Phragmites communis not influenced peatland. Grasses sedges, which produce large underground organs, showed whereas declined. Additionally, forbs declined nitrogen, most likely due competition populations grasses. Therefore, enrichment can promote dominance grasses, leading decrease mosses forbs.