Response of more than 1000 herbaceous species across 20 vegetation alliances to atmospheric deposition of nitrogen in the United States

This presentation will be given to the USDA Federal Atmospheric Resource Managers (FARM) monthly seminar series, and describes the initial results from a TITAN analysis of ~1000 herbaceous species vulnerability to N deposition across the U.S. We found species-level thresholds for 585 species (1.3−16.8 kg N ha−1 yr−1) that were decreasing in at least one habitat, and thresholds for 523 species (1.7−18.0 kg N ha−1 yr−1) that were increasing in at least one habitat.

Impact/Purpose

This is a part of AE.3.6.4 (Advances in Critical Loads and Quantifying the Impacts from Atmospheric Deposition on Natural Ecosystems), which extends our knowledge base by 5 times in terms of species sensitivity to N deposition. This is an extension of Clark et al. (2019) (STICS: ORD-027440) to use a new approach called a "TITAN" (Taxon Indicator Threshold Analysis, TITAN) to evaluate more species in terms of their vulnerability to atmospheric deposition.

Citation

Wilkins, K., C. Clark, AND J. Aherne. Response of more than 1000 herbaceous species across 20 vegetation alliances to atmospheric deposition of nitrogen in the United States. USDA FARM Monthly Science Series, Washington, DC, June 10, 2020.