This dataset was used to analyse effects of different biodiversity and functional group treatments, fertilizer and fungicide applications as well as weeding of vascular plants on the species richness and species composition of bryophytes for the following publication: Lin M., Bergamini A., Pichon N.A., Allan E, Boch S. 2025. Nitrogen enrichment and vascular plant richness loss reduce bryophyte richness. Scientific Reports. In this study we surveyed 96 of 216 2 m x 2 m experimental plots of the PaNDiv experiment, a large grassland field experiment in the Swiss lowlands (Pichon et al. 2020). In the PaNDiv experiment four experimental treatments were applied in a full-factorial design manipulating: (1) the nitrogen availability (through fertilization), (2) the presence of fungal pathogens (through fungicide application), (3) the functional composition of the vascular plant community (represented here by community-weighted mean (CWM) SLA), and (4) the vascular plant richness (sowing of either 1, 4, 8 or 20 species). To maintain the original sown vascular plant species richness and composition, one part of each plot (1.5 m × 2 m) was weeded, while the other part has been left unweeded since the beginning of the experiment (0.5 m × 2 m). On each plot we surveyed two subplots, the unweeded subplot and a weeded subplot of the same area (0.5 m × 2 m). On each subplot we established a complete list of all bryophyte species together with an estimate of their cover. The provided excel file contains three sheets: 1. A sheet with raw species lists of all plots surveyed together with information on all treatments and an estimation of the percentage cover of vascular plants in a summer campaign in August 2022. Cover of bryophytes was estimated for each species in percent. 2. A sheet with a list of all bryophyte species with its growth form (acroarpous/pleurocarpous) 3. A sheet with some explantations By means of the provided R code and the data in the excel file, all analyses can be repeated. More details to the data sampled can be found in Lin et al (2025).