Atmospheric nitrogen (N) deposition is altering biogeochemical cycling in forests and interconnected lakes of the northeastern US, and may shift nutrient limitation from N toward other essential elements, such as phosphorus (P). Whether this shift is occurring relative to N deposition gradients across the northeastern US has not been investigated. We used datasets for the northeastern US and the Adirondack sub-region to evaluate whether P limitation is increasing where N deposition is high at two geographic scales, based on N:P mass ratios. Using a model-selection approach, we determined that foliar N for dominant tree species and lake dissolved inorganic N (DIN) increased coincident with increasing N deposition, independent of relationships between foliar N or lake DIN and precipitation or temperature. Foliar P also increased with N deposition across the northeastern US for seven of eight deciduous species, but changed less across the Adirondacks.
Crowley, K.F.; McNeil, B.E.; Lovett, G.M.; Canham, C.D.; Driscoll, C.T.; Rustad, L.E.; Denny, E.; Hallett, R.A.; Arthur, M.A.; Boggs, J.L.; Goodale, C.L.; Kahl, J.S.; McNulty, S.G.; Ollinger, S.V.; Pardo, L.H.; Schaberg, P.G.; Stoddard, J.L.; Weand, M.P.; Weather, K.C. 2012. Do nutrient limitation patterns shift from nitrogen toward phosphorus with increasing nitrogen deposition across the northeastern United States. Ecosystems. 15: 940-957.