Fig. 3From: Nitrogen allocation in PM2.5 smoke-exposed plants: implications for ecosystem nitrogen cycling and stress responseChanges in N content of Schima superba and Cunninghamia lanceolata under smoke deposition. The letters “a, b, c, and d” and “A, B, C, and D” represent significant differences between the different smoke treatments and different days, respectively, i.e., p < 0.05Back to article page