Nitrogen deposition suppresses ephemeral post-fire plant diversity

Fire is a dominant force shaping patterns of plant diversity in Mediterranean-type ecosystems. In these biodiversity hotspots, including California’s endangered coastal scrub, many species remain hidden belowground as seeds and bulbs, only to emerge and flower when sufficient rainfall occurs after wildfire. The unique adaptations possessed by these species enable survival during prolonged periods of unfavorable conditions, but their continued persistence could be threatened by nonnative plant invasion and environmental change. Furthermore, their fleeting presence aboveground makes evaluating these threats in situ a challenge. For example, nitrogen (N) deposition resulting from air pollution is a well-recognized threat to plant diversity worldwide, but impacts on fire-following species are not well understood. We experimentally evaluated the impact of N deposition on post-fire vegetation cover and richness for three years in stands of coastal sage scrub that had recently burned in a larg..., Materials and methods
Study site
We conducted field experiments at a site in the Santa Monica Mountains National Recreation Area (34.151125, -118.964891) in stands of coastal sage scrub shrublands which burned in the May 2013 Springs Fire. The site last burned in 1993. The Santa Monica Mountains are adjacent to the highly urbanized Los Angeles metropolitan area and experience a steep gradient of anthropogenic N deposition. The study site where field plots were installed is located in the western end of the mountain range which receives moderate levels of exogenous N inputs, approximately 8 kg N ha-1 yr-1. Using aerial imagery and initial site surveys, we selected study areas of coastal sage scrub that were previously uninvaded by nonnative annual grasses before the fire, as well as adjacent areas at the ecotone of native shrublands and annual grasslands where both native shrub species and nonnative grasses were present before the fire (hereafter referred to as uninvaded and invaded, res..., , # Data from: Nitrogen deposition suppresses ephemeral post-fire plant diversity

Data includes plant cover (\"cover_data.csv\") and richness (\"richness_data.csv\") from nitrogen fertilization plots over three years following wildfire, including in both previously invaded and uninvaded shrublands. Also included is a species list of all plant species recorded during the study (\"species_list.csv\").

## Description of the data and file structure

**species_list.csv**: This file contains full species names (genus and species) for all plant species recorded during the study. Also included are species codes used in the plant cover and richness data file, as well each specie's growth form (i.e., perennial or annual, forb, grass or shrub) and origin (either native to the site or nonnative), and plant family.

**cover_data.csv**: Data file includes percent cover (%) of each plant species within field plots, as well as percent bare ground (\"Bare\") and litter (\"Litter\"). Nitrogen fertilization plots...