Supporting Online Material (SOM) For

Keyan Fang et al.

Supporting Online Material (SOM) for

Spatiotemporal variability of treegrowth over Northwest China and its association with climate

Running title: Climate-growth interactions in NW China

Keyan Fang, Xiaohua Gou, Fahu Chen

Key Laboratory of Western China’s Environmental Systems (MOE), Research School of Western Environment and Climate Change, Lanzhou University, Lanzhou China, 730000

Edward Cook

Tree-Ring Lab, Lamont-Doherty Earth Observatory of Columbia University, New York, NY USA 10964

Jinbao Li

International Pacific Research Center, School of Ocean and Earth Science and Technology, University of Hawaii,Honolulu, HI USA 96882

Yingjun Li

Key Laboratory of Western China’s Environmental Systems (MOE), Lanzhou University, Lanzhou China, 730000

This file contains:

Table S1 to S3

References

Figure S1

Table S1 Site and chronology statistics of various locations which were grouped into clusters as shown in Figure 1. The explained variances for clusters of F, H and I were not shown, because these groupings were not based solely on results of RPCA.

Group / Explained
Variance / ID* / Species / Time Span** / Longitude
(°E) / Latitude
(°N) / Elevation
(m a.s.l.) / Reference
DEZQIN / PIFL / 1358-2004 / 100.49 / 34.45 / 3495 / [Peng et al., 2008]
GOUQIN / JUPR / 1382-2004 / 100.48 / 34.44 / 3370
HEBQIN / JUPR / 1600-2004 / 100.47 / 34.44 / 3385
LAJQIN / JUPR / 1522-2004 / 100.43 / 34.43 / 3375
MQAXJP / JUPR / 1166-2001 / 100.21 / 35.04 / 3540 / [Gou et al., 2008]
MQBXJP / JUPR / 1090-2002 / 99.47 / 34.47 / 3600
MQDXJP / JUPR / 1350-2002 / 99.40 / 34.43 / 3650
A / 16.7% / MQFXJP / JUPR / 1279-2002 / 99.41 / 34.45 / 3675
MQRXJP / JUPR / 1090-2002 / 99.41 / 34.45 / 3665
TDAXJP / JUPR / 1490-2002 / 100.48 / 34.47 / 3290
TDBXJP / JUPR / 1540-2002 / 100.49 / 34.47 / 3350
HBLXJP / JUPR / 1570-2002 / 100.49 / 34.47 / 3880
HBMXJP / JUPR / 1510-2002 / 100.49 / 34.47 / 3890
HBHXJP / JUPR / 1563-2002 / 100.49 / 34.47 / 3957
DQHZHO / JUPR / 1433-2004 / 100.04 / 35.00 / 3722 / [Peng et al., 2008]
SYKRWL / PITA / 1776-1999 / 105.98 / 38.72 / 2150 / [Li et al., 2007]
BSIRWL / PITA / 1820-1999 / 105.98 / 38.72 / 2175
XINLOL / PIWI / 1829-2003 / 103.98 / 35.27 / 2370 / [Fang et al., 2009]
XINLML / PIWI / 1805-2003 / 104.01 / 35.30 / 2460
XINLOM / PIWI / 1836-2003 / 104.03 / 35.46 / 2570
B / 15.5% / XINLOH / PIWI / 1843-2003 / 104.09 / 35.51 / 2660
TULUGH / PICR / 1865-2003 / 102.65 / 36.58 / 2690
TULGHM / PICR / 1899-2003 / 102.67 / 36.59 / 2630
TULGLM / PICR / 1881-2003 / 102.69 / 36.61 / 2550
TULGOL / PICR / 1912-2003 / 102.71 / 36.63 / 2325
MOSIGH / PITA / 1887-2003 / 102.91 / 36.81 / 2400
MOSIHM / PITA / 1912-2003 / 102.93 / 36.82 / 2340
MOSILM / PITA / 1890-2003 / 102.94 / 36.84 / 2290
MOSIGL / PITA / 1897-2003 / 102.95 / 36.86 / 2230
KENGPS / PISC / 1729-2004 / 81.43 / 42.48 / 2593 / [Cook et al., 2010]
BIGKPS / PISC / 1713-2004 / 82.08 / 42.53 / 2610
BEQURU / PISC / 1760-1993 / 87.07 / 43.08 / 2440 / [Yuan et al., 2003]
HXBURU / PISC / 1719-1993 / 87.11 / 43.11 / 2360
XGSURU / PISC / 1770-1993 / 87.14 / 43.16 / 2070
C / 12.0% / ZEDURU / PISC / 1743-1993 / 87.03 / 43.13 / 2390
FUKBAI / PISC / 1877-2004 / 88.15 / 43.95 / 1820 / [Cook et al., 2010]
JIALPS / PISC / 1674-2004 / 82.09 / 43.04 / 2308
GOLQIA / PISC / 1737-2004 / 82.69 / 43.08 / 1710
KUERPS / PISC / 1696-2004 / 82.52 / 43.09 / 1499
HUTXIA / PISC / 1786-2004 / 86.30 / 43.79 / 1900
HUTSHI / PISC / 1846-2004 / 86.70 / 43.71 / 1910
TIANPS / PISC / 1728-2004 / 88.07 / 43.53 / 1925
MIQAPS / PISC / 1713-2002 / 87.55 / 43.46 / 1980 / [Li et al., 2006]
MIQBPS / PISC / 1689-2002 / 88.01 / 43.48 / 2070
WULANJ / JUPR / 0-2000 / 98.41 / 37.02 / 3704 / [Zhang et al., 2003]
DULAJP / JUPR / 900-1993 / 98.05 / 36.18 / 3800 / [Sheppard et al., 2004]
SHENJP / JUPR / 900-1993 / 98.05 / 37.00 / 3653
D / 8.2% / DUSHJP / JUPR / 876-1993 / 98.05 / 36.39 / 3324
DELINH / JUPR / 990-2001 / 97.93 / 37.45 / 3600 / [Zhang and Qiu, 2007]
TIAANG / ABCH / 1911-2005 / 106.47 / 34.25 / 2510
TIALEN / ABCH / 1857-2005 / 106.25 / 34.35 / 2234
E / 4.7% / TIAZHA / ABCH / 1856-2005 / 106.55 / 34.19 / 2375
HUASPI / PIAR / 1589-1990 / 110.05 / 34.29 / 2020 / [Shao and Wu, 1994]
SANGTS / TSCH / 1725-1992 / 107.48 / 33.39 / 1540 / [Liu and Shao, 2003]
F / GHEGAN / JUPR / 1795-2000 / 101.32 / 37.56 / 2800 / [Gou et al., 2005]
YINBPS / PISC / 1735-2000 / 101.36 / 37.48 / 2895
G / 2.9% / BLKALS / LASI / 1718-2002 / 93.18 / 43.51 / 2810 / [Peng et al., 2008]
BLKBLS / LASI / 1802-2002 / 93.23 / 43.50 / 2840
H / QUMAJP / JUPR / 1584-2002 / 96.08 / 33.48 / 4225 / [Qin et al., 2003]
ZHIDJP / JUPR / 1486-2002 / 96.17 / 33.43 / 4215
I / YCHAPS / PISC / 1764-2001 / 76.59 / 37.36 / 2920
YCHBPS / PISC / 1666-2001 / 77.00 / 37.36 / 2750
Others / ZHANGX / PITB / 1616-2006 / 104.28 / 34.38 / 2436 / [Fang et al., 2010]
SUNLZU / JUPR / 1686-2000 / 98.48 / 38.58 / 2312 / [Gou et al., 2005]

* LASI = Larix sibirica; PISC = Picea schrenkiana; PIWI = Picea wilsonii; PICR = Picea crassifolia; JUPR = Juniperus przewalskii; PIFL = Pinus flexilis; PIAR = Pinus armandii; PITA = Pinus tabulaeformis; TSCH = Tsuga chinensis; ABCH = Abies chensiensis

** based on the reliable portion of each chronology (more than 6 tree-ring cores)

Table S2 Clusters based on climate-growth response functions for temperature and precipitation from previous May to current September. The ID and groupings (A-I) are shown in Table 2.

Cluster / Explained
variance / ID for each cluster
1 / 15.3% / Group B (SYKRWL XINLOL XINLML XINLOM XINLOH TULUGH TULGHM TULGLM TULOGL MOSIGH MOSIHM MOSILM MOSIGL)
2 / 11.7% / Group D (DELINH DULAJP SHENJP DUSHJP WULANJ); SUNLZU
3 / 11.1% / Group C (MIQAPS MIQBPS KUERPS TIANPS FUKBAI GOLQIA HUTXIA HUTSHI); Group I (YCHAPS YCHBPS)
4 / 9.1% / Group F (GHEGAN, YINBPS); Group A (MQAXJP, MQBXJP HBHXJP, HBLXJP, HBMXJP)
5 / 9.0% / Group A (DEZQIN, GOUQIN, HEBQIN, LAJQIN, TDAXJP, TDBXJP)
6 / 7.7% / Group A (MQDXJP, MQFXJP, MQRXJP); Group H (QUMAJP, ZHIDJP)
7 / 6.0% / Group C (BEQURU, HXBURU, XGSURU, ZEDURU)
8 / 5.4% / Group C (BIGKPS, KENGPS)
Others / DQHZHO BSIRWL JIALPS TIAANG TIALEN TIAZHA HUASPI SANGTS BLKALS BLKBLS ZHANGX

Table S3 Classifications for drought-growth responses.

Cluster / Explained
variance / ID for each cluster
1 / 23.5% / MIQAPS MIQBPS JIALPS DELINH GOUQIN HEBQIN GHEGAN DULAJP SHENJP DUSHJP MQAXJP MQBXJP MQDXJP MQFXJP MQRXJP TDAXJP TDBXJP HBLXJP HBMXJP HBHXJP HUASPI YINBPS WULANJ QUMAJP ZHIDJP ZHANGX DQHZHO SYKRWL MOSIGH MOSIHM MOSILM MOSIGL
2 / 18.1% / KUERPS TIANPS YCHAPS BEQURU HXBURU XGSURU ZEDURU LAJQIN SANGTS XINLOL XINLML XINLOM XINLOH TULUGH TULGHM TULGLM TULOGL HUTXIA TIAANG
others / BLKALS BLKBLS BIGKPS KENGPS YCHBPS SUNLZU BSIRWL DEZQIN GOLQIA HUTSHI FUKBAI TIALEN TIAZHA

Figure S1. Monthly total precipitation for some stations in NW China according to the instrumental records since the 1950s. The Xining station is close to Group A, D and H and shows the monthly precipitation pattern over that region, the Lanzhouand Zhongning stations show precipitation diagramsof Groups B and E, the Wulumuqi and Yining stations indicate distribution of monthly precipitation of Group C, the Xi’an station shows the monthly precipitation of Group F, the Hami station displays the monthly precipitation of Group G, and the Hetian station indicate precipitation patterns of Group I.

References:

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