Leaf Gas Exchange and Nutrient Use Efficiency Help Explain the Distribution of Two Neotropical Mangroves under Contrasting Flooding and Salinity

Table 1

Mixed model ANOVA results describing leaf gas exchange variables for seedlings of Rhizophora mangle and Laguncularia racemosa grown in mixed culture under different salinity and hydroperiod treatments.

Source of variation	DF, DFerror	A	𝐶𝑖	𝑔𝑤	PWUE	DF, DFerror	PNUE
Species	1, 5	ns	***	***	***	1, 20.1	*
Salinity	1, 5	*	***	**	**	1, 20.8	***
Hydroperiod	1, 5	ns	ns	ns	ns	1, 20.8	ns
Species × salinity	1, 5	ns	**	ns	**	1, 20.1	ns
Species × hydroperiod	1, 5	ns	ns	ns	ns	1, 20.1	ns
Salinity × hydroperiod	1, 5	ns	**	*	ns	1, 20.8	ns
Species × salinity × hydroperiod	1, 5	*	ns	**	ns	1, 20.1	ns
Month	1, 5	***	***	***	***	—	—
Salinity × month	1, 5	ns	ns	**	**	—	—
Species × month	1, 5	ns	ns	*	ns	—	—
Hydroperiod × month	1, 5	ns	ns	*	ns	—	—
Salinity × species × month	1, 5	*	ns	ns	ns	—	—

NS: not significant at the 0.05 level; *significant at 0.01–0.05 level; **significant at 0.01–0.001 level; ***significant at <0.001 level.
A: assimilation; 𝐶_𝑖: leaf intercellular CO₂ concentration; 𝑔_𝑤: stomatal conductance; PWUE: instantaneous photosynthetic water use efficiency; PNUE: photosynthetic nitrogen use efficiency.