气候变化领域集成服务门户(CCPortal): Tree growth and intrinsic water-use efficiency of inland riparian forests in northwestern China: evaluation via delta C-13 and delta O-18 analysis of tree rings

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DOI	10.1093/treephys/tpu067
	Tree growth and intrinsic water-use efficiency of inland riparian forests in northwestern China: evaluation via delta C-13 and delta O-18 analysis of tree rings
	Liu, Xiaohong; Wang, Wenzhi; Xu, Guobao; Zeng, Xiaomin; Wu, Guoju; Zhang, Xuanwen; Qin, Dahe
发表日期	2014
ISSN	0829-318X
起始页码	966
结束页码	980
卷号	34 期号:9
英文摘要	The rising atmospheric CO2 concentration (C-a) has increased tree growth and intrinsic water-use efficiency (iWUE). However, the magnitude of this effect on long-term iWUE and whether this increase could stimulate the growth of riparian forests in extremely arid regions remain poorly understood. We investigated the relationship between growth [ring width; basal area increment (BAI)] and iWUE in a riparian Populus euphratica Oliv. forest to test whether growth was enhanced by increasing CO2 and whether this compensated for environmental stresses in the lower reaches of the inland Heihe River, northwestern China. We accomplished this using dendrochronological methods and carbon (delta C-13) and oxygen (delta O-18) isotopic analysis. We found an increase in BAI before 1958, followed by a decrease from 1958 to 1977 and an increase to a peak around 2000. Tree-ring carbon discrimination (Delta) and delta O-18 indicated significant negative overall trends from 1920 to 2012. However, the relationship shifted in strength and direction around 1977 from significantly negative to a weak connection. The seasonal minimum temperature in April to July showed strong influence on Delta, and delta O-18 was controlled by relative humidity (negatively correlated) and temperature (positively correlated) in June and July. The patterns of internal to atmospheric CO2 (C-i/C-a) suggest a specific adaptation of tree physiology to increasing CO2. Intrinsic water-use efficiency increased significantly (by 36.4%) during the study period. The increased iWUE explained 19.8 and 39.1% of the observed yearly and high-frequency (first-order difference) variations in BAI, respectively, after 1977. Our results suggest significant CO2 stimulation of riparian tree growth, which compensated for the negative influences of reductions in river streamflow and a drying climate during the study period.
英文关键词	CO2 fertilization; stable isotopes
WOS研究方向	Forestry
WOS类目	Forestry
来源期刊	TREE PHYSIOLOGY
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/158587
作者单位	Liu, XH (corresponding author), Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China.
推荐引用方式 GB/T 7714	Liu, Xiaohong,Wang, Wenzhi,Xu, Guobao,et al. Tree growth and intrinsic water-use efficiency of inland riparian forests in northwestern China: evaluation via delta C-13 and delta O-18 analysis of tree rings[J],2014,34(9).
APA	Liu, Xiaohong.,Wang, Wenzhi.,Xu, Guobao.,Zeng, Xiaomin.,Wu, Guoju.,...&Qin, Dahe.(2014).Tree growth and intrinsic water-use efficiency of inland riparian forests in northwestern China: evaluation via delta C-13 and delta O-18 analysis of tree rings.TREE PHYSIOLOGY,34(9).
MLA	Liu, Xiaohong,et al."Tree growth and intrinsic water-use efficiency of inland riparian forests in northwestern China: evaluation via delta C-13 and delta O-18 analysis of tree rings".TREE PHYSIOLOGY 34.9(2014).