Table 1.

Results of nonparametric tests on two levels, groundwater/stream and xylem water precipitation offsets

Site/paper ID	dxylem		dxylem_c
	Prob>|Z|	Prob > ChiSq	Prob>|Z|	Prob > ChiSq
2	<0.0001	<0.0001	0.2478	0.2468
3	0.0058	0.0055	0.0039	0.0037
4	0.2616	0.2207	0.6098	0.5403
5	<0.0001	<0.0001	0.0002	0.0002
6	0.0016	0.0016	0.6954	0.6839
7	0.0189	0.0143	0.3583	0.3074
8	<0.0001	<0.0001	0.0189	0.0188
9	<0.0001	<0.0001	0.0223	0.0221
10	0.302	0.2664	0.0472	0.039
12	0.0021	0.0019	0.0007	0.0007
13	0.6366	0.5708	0.0107	0.0082
14	0.1694	0.1674	<0.0001	<0.0001
15	0.0038	0.0037	<0.0001	<0.0001
16	<0.0001	<0.0001	0.8696	0.8578
17	<0.0001	<0.0001	0.1966	0.1893
18	<0.0001	<0.0001	0.0086	0.0086
19	0.0027	0.0026	0.1093	0.1063
20	0.0022	0.0018	0.0933	0.0826
21	0.0167	0.0164	<0.0001	<0.0001
22	0.3865	0.2482	0.1489	0.0833
23	<0.0001	<0.0001	0.0094	0.0093
24	<0.0001	<0.0001	0.006	0.006
26	<0.0001	<0.0001	<0.0001	<0.0001
27	<0.0001	<0.0001	<0.0001	<0.0001
29	0.0011	0.0009	0.0128	0.0112
30	0.4211	0.4124	0.001	0.0009
32	0.0171	0.0164	0.0437	0.042
35	<0.0001	<0.0001	<0.0001	<0.0001
36	0.0018	0.0016	0.007	0.0063
40	0.5076	0.5038	<0.0001	<0.0001
41	<0.0001	<0.0001	<0.0001	<0.0001
42	0.0135	0.0106	0.05	0.0408
43	<0.0001	<0.0001	0.0038	0.0038
44	<0.0001	<0.0001	0.0021	0.002
45	0.4306	0.4116	0.0001	0.0001
46	<0.0001	<0.0001	0.0051	0.005
47	<0.0001	<0.0001	0.031	0.0308

For these two levels, Prob>|Z| and Prob > ChiSq columns show the P values of the Wilcoxon (Mann−Whitney) test based on normal distribution approximations and the Kruskal−Wallis test based on one-way ChiSquare (ChiSq) approximations, respectively. The d_xylem is based on the precipitation offset values in ref. 2; d_{xylem_c} is based on the CVD error-corrected precipitation offset values using SI Appendix, equation S3 in ref. 1.