E&S research focused on biodiversity at Hubbard Brook Experimental Forest in NH, Shenandoah NP in VA, and Great Smoky Mountains NP in TN has been published in the journal Environmental Pollution. Two model chains, VSD+PROPS and ForSAFE-Veg, were used to evaluate effects of future climatic and atmospheric nitrogen deposition conditions on understory vegetation and to determine critical loads of nitrogen deposition needed to protect terrestrial plant biodiversity.