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The simulated effects of nitrogen fertilization and water shortage on daily potential canopy transpiration (E_cp; A–D), gross photosynthesis (A_cp,gross; E–H), and canopy photosynthetic water-use efficiency (PWUE_cp; I–L). and canopy photosynthetic nitrogen-use efficiency (PNUE_cp; M–P). “Measured LAI and SLN” line: the default simulations performed using the measured leaf area index (LAI) and specific leaf nitrogen (SLN) at each nitrogen level or each water level. “Measured SLN” line: simulations performed with measured SLN at each nitrogen level (or each water level) while keeping LAI fixed at the values of non-fertilization (or water-stressed) treatment. “Measured LAI” line: simulations performed with measured LAI at each nitrogen level (or each water level) while keeping SLN fixed at the values of non-fertilization (or water-stressed) treatment. Linear growth-2015 (A,E,I,M) denotes the case where the values of LAI and SLN were collected at the linear growth stage in the field experiment in 2015; Flowering-2015 (B,F,J,N) denotes the case where the values of LAI and SLN were collected at full flowering in the field experiment in 2015; CAN1 (C,G,K,O) denotes the case where the values of LAI and SLN were collected in the CAN1; CAN2 (D,H,L,P) denotes the case where values of LAI and SLN were collected in the CAN2. N0, N30, N60, N120 denote nitrogen fertilization rate in 2015 at 0, 30, 60, and 120 kg N ha⁻¹, respectively; N1, N2, and N3 denote nitrogen fertilization rate in CAN1 at 0, 1.0, and 2.0 g N container⁻¹, respectively. Note the x-axes of the N treatment are not on scale. WW denotes well-watered containers in CAN2 while WS denotes the containers where water supply was half of WW.