Table 2.

Gas-exchange parameters of control and nZVI-exposed Arabidopsis at 21 days.

Treatment	CO2 Assimilation Rate (μmol∙m−2∙s−1)	Stomatal Conductance (mol∙m−2∙s−1)	Intracellular CO2 Concentration (μL∙L−1)	Transpiration Rate (mmol∙m−2∙s−1)
Control	4.1 ± 0.4 a	0.15 ± 0.02 a	340 ± 4 a	2.1 ± 0.5 a
nZVI	5.2 ± 0.4 b	0.21 ± 0.03 b	348 ± 2 b	3.1 ± 0.3 b

Measurements were conducted at 380 μL∙L⁻¹ CO₂. Results are shown as mean ± standard error (n = 6). Letters indicate significant differences between groups (p < 0.05 by Student’s t-test).