Electronic supplementary material for
Human activity impacts on the stem radial growth of Populus euphratica riparian forests in China’s
Ejina Oasis, using tree-ring analysis
Xiaomei Peng 1,2 Shengchun Xiao 1 * Guodong Cheng 1 Honglang Xiao 1 Quanyan Tian 1, 2 Qibing
Zhang 3
1 Key Laboratory of Ecohydrology of Inland River Basin, Cold and Arid Regions Environmental and
Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China
2 University of the Chinese Academy of Sciences, Beijing 100049, China
3 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese
Academy of Sciences, Beijing 100093, China
* Corresponding author
Tel.: 86-0931-496-7126;
Fax: +86-931-827-3894;
E-mail: xiaosc@lzb.ac.cn;
Address: Donggang West Road 320, Lanzhou, Gansu, China;
Zip Code: 730000
Captions
ESM. 7 Correlation coefficients between pairs of chronologies based on data from the period covered by the shorter of the two chronologies in each pair.
ESM. 8 Correlation coefficients between each ring-width chronologies at the 28 sites and precipitation, temperature and runoff data.
ESM. 9 Annual average groundwater depth at the 5 wells from 1989 to 2008
Introduction
This dataset contains the results of the correlation analysis for the relationships between pairs of the 28 chronologies, and their correlation with the precipitation, temperature and runoff data.

BYE
BYW
MSQ2
SD
WDQ
DD
BG
QD2
BDQ
DX
EJP
CK
JG3
HH4
HX2
HBY
LX2
LXE
HNL
ER
DW
JD
HT
LX
LXW
CG
UPB
HJG
ESM. 7 Correlation coefficients between pairs of chronologies based on data from the period covered by the shorter of the two chronologies in each pair. The periods of the chronologies are presented in
Table 3.
The absolute values of the correlation coefficients are represented by the circle’s diameter in a 1×1 square. The significance of the correlation coefficients is shown as follows: , significant positive correlation at P < 0.05; , non-significant positive correlation; , significant negative correlation at P
< 0.05; , non-significant negative correlation.

WDQ
DD
BG
QD2
BDQ
DX
EJP
CK
LX2
LXE
HNL
ER
BYE
BYW
MSQ2
SD
DW
JD
HT
LX
LXW
CG
UPB
HJG
JG3
HH4
HX2
HBY
F0 F1 P9 P10 P11 P12 C1 C2 C3 C4 C5 C6 C7 C8 C9 a
DW
JD
HT
LX
LXW
LXE
HNL
ER
BYE
BYW
MSQ2
SD
WDQ
CG
UPB
HJG
JG3
HH4
HX2
HBY
LX2
DD
BG
QD2
BDQ
DX
EJP
CK
F0 F1 P9 P10P11P12 C1 C2 C3 C4 C5 C6 C7 C8 C9 c
F0 F1 P9 P10 P11 P12 C1 C2 C3 C4 C5 C6 C7 C8 C9
DW
JD
HT
LX
LXW
LXE
HNL
ER
BYE
BYW
MSQ2
SD
CG
UPB
HJG
JG3
HH4
HX2
HBY
LX2
WDQ
DD
BG
QD2
BDQ
DX
EJP
CK b
ESM. 8 Correlation coefficients between each ring-width chronologies at the 28 sites (y-axis) and a precipitation data (at the Ejina meteorological station from 1957 to 2010, x-axis), b temperature data (at the
Ejina meteorological station from 1957 to 2010, x-axis), c runoff data (at the Zhengyixia hydrologic station from 1954 to 2010, x-axis). The precipitation data, runoff data, temperature data included annual precipitation, annual runoff, annual mean temperature during the current year (F0) and the previous year
(F1), and the monthly precipitation, monthly runoff, monthly mean temperature from the previous
September to the current September (P9, P10…C1,
C9).
The absolute values of the correlation coefficients are represented by the circle’s diameter in a 1×1 square.
The significance of the correlation coefficients is shown as follows: , significant positive correlation at
P < 0.05; : nonsignificant positive correlation; , significant negative correlation at P < 0.05; , nonsignificant negative correlation.

5
6
7
2
3
4
0
1988
1
Year
1992 1996 the degradation period
2000 2004 2008
3
4
1
2
5
ESM. 9 Annual average groundwater depth at the 5 wells from 1989 to 2008. The locations of the five wells are shown in Fig. 1b, and some data are discontinuous. The data covered only one year of the natural runoff period (1989) because of the available continuous data.