Table 1 Summary of analysis of Linear Mixed Model (LMM) of the effects of warming (T), altered precipitation (P) and their interactions on soil nitrogen (N) stocks in the topsoil (0–20 cm), the subsoil (40–70 cm) and the entire soil profile (0–70 cm) (Overall).

Variables	Factors d.f.	Topsoil (0–20 cm)				Subsoil (40–70 cm)				Overall (0–70 cm)
		B	T	P	T × P	B	T	P	T × P	B	T	P	T × P
		3	1	2	2	3	1	2	2	3	1	2	2
STN	F	1.757	0.325	0.358	0.934	1.070	0.076	0.946	3.043	1.804	0.102	0.408	1.723
STN	P	0.199	0.577	0.705	0.415	0.391	0.787	0.410	0.078	0.190	0.754	0.672	0.212
NH4⁺-N	F	4.760	2.547	1.620	0.159	1.147	0.245	0.642	0.156	4.426	1.995	1.373	0.353
NH4⁺-N	P	0.016 *	0.131	0.231	0.854	0.362	0.628	0.540	0.857	0.020 **	0.178	0.283	0.708
NO3⁻-N	F	2.849	10.976	25.552	0.614	0.606	0.001	0.201	0.431	2.020	3.306	5.739	0.643
NO3⁻-N	P	0.073	0.005 **	0.000 **	0.554	0.621	0.974	0.820	0.658	0.154	0.089	0.014 *	0.540
DON	F	1.358	0.461	7.136	0.200	14.176	2.573	2.308	0.411	11.553	2.698	1.888	0.727
DON	P	0.293	0.508	0.007 **	0.821	0.000 **	0.130	0.134	0.670	0.000 **	0.121	0.186	0.499
AAN	F	9.451	1.905	13.846	0.185	3.435	0.227	0.364	0.929	10.000	1.028	7.583	0.113
AAN	P	0.001 **	0.188	0.000 **	0.833	0.044 *	0.641	0.701	0.416	0.001 **	0.327	0.005 **	0.894
MBN	F	3.034	10.147	11.070	0.488	1.991	0.055	2.794	3.538	5.104	3.768	1.074	0.874
MBN	P	0.062	0.006 **	0.001 **	0.623	0.159	0.817	0.093	0.055	0.012 *	0.071	0.367	0.438

Warming and precipitation treatments were included as fixed effects, and block (B) was included as a random effect. STN, soil total nitrogen; SIN, soil inorganic N; NH₄⁺-N, ammonium-N; NO₃⁻-N, nitrate-N; SON, soil organic N; DON, dissolved organic N (2 M KCl extracts); AAN, amino acid N; MBN, microbial biomass N; d.f., degrees of freedom. ^**P < 0.01; ^*P < 0.05. Red asterisks indicate the positive effects; Blue asterisks indicate the negative effects.

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