Table 4. Seasonal variation of the predawn (ψ_p) and midday (ψ_m) leaf water potentials in Populus sibirica and Ulmus pumila across different treatments measured in July 2021 and July 2022.

Different lowercase letters indicate significant differences among the treatments at α = 0.05.

Species	Treatments	ψ p		ψ m
		July, 2021	July, 2022	July, 2021	July, 2022
Populus sibirica	CONT	−0.82 ± 0.11c	−0.86 ± 0.56ab	−1.29 ± 0.05abc	−1.71 ± 0.53bc
	2 L h−1	−0.41 ± 0.08abc	−0.66 ± 0.47c	−1.10 ± 0.07a	−1.98 ± 0.38c
	4 L h−1	−0.35 ± 0.01ab	−1.01 ± 0.36abc	−1.09 ± 0.02a	−1.72 ± 0.19bc
	8 L h−1	−0.40 ± 0.04abc	−0.97 ± 0.17abc	−1.53 ± 0.09cd	−1.43 ± 0.27ab
	NPK	–	–	–	–
	2 L h−1+NPK	−0.51 ± 0.03c	−0.61 ± 0.2a	−1.38 ± 0.08bc	−1.45 ± 0.35ab
	4 L h−1+NPK	−0.52 ± 0.06c	−0.66 ± 0.30a	−1.63 ± 0.09de	−1.34 ± 0.35ab
	8 L h−1+NPK	−0.31 ± 0.05a	−0.83 ± 0.46ab	−1.5 ± 0.09bcd	−1.55 ± 0.29abc
	COMP	–	–	–	–
	2 L h−1+COMP	−0.51 ± 0.03c	−0.89 ± 0.15bc	−1.85 ± 0.10e	−1.28 ± 0.17ab
	4 L h−1+COMP	−0.48 ± 0.04bc	−1.13 ± 0.57bc	−1.27 ± 0.03ab	−1.28 ± 0.52ab
	8 L h−1+COMP	−0.35 ± 0.03ab	−1.19 ± 0.48bc	−1.69 ± 0.07de	−2.74 ± 0.24bc
Ulmus pumila	CONT	−1.91 ± 0.18b	−2.33 ± 0.53e	−2.74 ± 0.07c	−2.46 ± 0.54bc
	2 L h−1	−0.57 ± 0.07a	−1.78 ± 0.26de	−1.77 ± 0.12ab	−1.99 ± 0.24ab
	4 L h−1	−0.48 ± 0.02a	−1.27 ± 0.57abcd	−1.79 ± 0.04ab	−1.96 ± 0.35ab
	8 L h−1	−0.71 ± 0.05a	−0.98 ± 0.21abc	−1.62 ± 0.49a	−1.68 ± 0.65a
	NPK	−2.08 ± 0.22b	−1.59 ± 0.26dc	−2.35 ± 0.17bc	−2.86 ± 0.28c
	2 L h−1+NPK	−0.80 ± 0.10a	−1.34 ± 0.10bcd	−1.92 ± 0.06ab	−1.54 ± 0.16a
	4 L h−1+NPK	−0.90 ± 0.02a	−0.66 ± 0.35a	−1.79 ± 0.04a	−1.51 ± 0.56a
	8 L h−1+NPK	−0.71 ± 0.05a	−0.83 ± 0.16ab	−1.86 ± 0.07ab	−1.55 ± 0.48a
	COMP	−1.11 ± 0.64a	−1.43 ± 0.28bcd	−2.56 ± 0.12c	−2.15 ± 0.28ab
	2 L h−1+COMP	−0.70 ± 0.05a	−0.99 ± 0.25abc	−1.79 ± 0.11ab	−1.89 ± 0.26ab
	4 L h−1+COMP	−0.60 ± 0.01a	−1.08 ± 0.24abc	−1.49 ± 0.08a	−1.87 ± 0.23ab
	8 L h−1+COMP	−0.43 ± 0.07a	−1.35 ± 0.36bcd	−1.59 ± 0.26a	−2.05 ± 0.35ab