Emissions of atmospheric reactive nitrogen (N) have increased globally due to agricultural and industrial activities, resulting in substantial increases in deposition rates relative to pre-industrial levels. The observed ecological consequences of anthropogenic N deposition include ecosystem eutrophication and acidification, and losses of biodiversity. This session will explore the patterns of biodiversity changes in terrestrial ecosystems due to N deposition and the potential consequences for those changes. We will first review the observed changes and causes of biodiversity change, focusing primarily on plant and microbial responses. We will then examine the potential consequences of these losses in terms of plant-mycorrhizal interactions, plant-consumer interactions, invasibility of communities and susceptibility to altered disturbance regimes, and transmission of disease.