干旱区生态环境知识资源中心(Arid): 干旱胁迫对拉萨半干旱河谷主要乔木树种幼树耗水及光合特性的影响

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	干旱胁迫对拉萨半干旱河谷主要乔木树种幼树耗水及光合特性的影响
其他题名	Effect of drought stress on characteristics of water consumption and photosynthesis for main arbor species in semi-arid valley of Lhasa
	辛福梅; 杨小林; 赵垦田; 罗桑卓玛
来源期刊	浙江大学学报. 农业与生命科学版
ISSN	1008-9209
出版年	2016
卷号	42 期号:2 页码:199-208
中文摘要	在拉萨半干旱河谷以三年生藏川杨、银白杨、左旋柳和榆树为研究对象,通过盆栽控制试验,采用盆栽苗木称量法和Li-6400光合测定法,研究在轻度、中度和重度干旱胁迫(土壤含水量分别为田间持水量的70%~75%、50%~55%和30%~35%)条件下4个树种的蒸腾耗水特性和水分利用效率。结果表明:1)正常供水时,藏川杨、银白杨、左旋柳和榆树白天耗水量分别为1 096.5、1 363.8、915.1、702.9 g/m~2,藏川杨和左旋柳白天耗水量显著低于银白杨;轻度干旱时左旋柳和榆树的全天总耗水量和白天总耗水量均有明显增加,其中左旋柳的增幅分别达到38.1%和40.8%,榆树的增幅分别为30.1%和28.7%,其余2个树种均有不同程度的下降;中度干旱时4种苗木耗水量均有下降;重度干旱时耗水量最小。2)正常供水时,银白杨和左旋柳的耗水速率日变化为双峰曲线,峰值均出现在12:00-14:00和16:00-18:00,藏川杨和榆树为单峰曲线,峰值出现在12:00-14:00;轻度干旱时,银白杨为双峰曲线,第1峰值出现在12:00-14:00,其余3个树种为单峰曲线;中度和重度干旱时各树种耗水速率均表现为单峰曲线。3)随干旱加剧,藏川杨和银白杨的净光合速率和蒸腾速率均逐步下降;左旋柳的净光合速率和蒸腾速率均在轻度干旱时最大,在其余3个水分条件下随干旱加剧,其净光合速率和蒸腾速率逐渐下降;榆树的净光合速率和蒸腾速率相对较低,最大值均出现在轻度干旱下,重度干旱时其值显著小于其余处理。4)藏川杨在中度和重度干旱时水分利用效率高于正常供水和轻度干旱;银白杨在各干旱胁迫下水分利用效率均相对较低;随干旱加剧,左旋柳的水分利用效率逐渐增加;榆树在重度干旱时水分利用效率显著高于其余3个处理。综上所述,4个树种均能耐受一定程度的水分亏缺,属耐旱较强的树种,综合各因素,其耐旱性排序为榆树>藏川杨>左旋柳>银白杨。
英文摘要	Water is a main limiting factor in arid and semi-arid areas, so the core technical problem for afforestation is how to ensure and maintain basic water demand for normal growth and development of trees. Investigation on the actual transpiration water consumption of main afforestation tree species can provide important guidance and theoretical basis for density control, water use, forest stability, woodland water balance and environmental capacity estimation of water resources of artificial vegetation. In this paper, four arbor species Populus szechuanica var. tibetica, Populus alba, Salix paraplesia var. subintegra and Ulmus pumila of three years old were selected in semi-arid valley of Lhasa, water consumptions of which were measured by pot seedling weight method, and net photosynthetic rate (Pn), transpiration rate (Tr) and water use efficiency (WUE) of them were investigated by Li-6400 photosynthetic system measuring method under different drought stresses. The stress treatments included normal water supply (90%-95% of field moisture capacity, CK), light drought stress (70%-75% of field moisture capacity, LS), moderate drought stress (50%-55% of field moisture capacity, MS) and heavy drought stress (30%-35% of field moisture capacity, HS) on potted experiments. The results showed that: 1) Under the normal water supply, the day water consumptions of P. szechuanica var. tibetica, P. alba, S. paraplesia var. subintegra and U. pumila seedlings were 1 096.5, 1 363.8, 915.1 and 702.9 g/m~2, respectively. The water consumption of native trees (P. szechuanica var. tibetica and S. paraplesia var. subintegra) was significantly lower than that of P. alba. Under the light drought stress, the day-and-night and day water consumptions of S. paraplesia var. subintegra and U. pumila increased significantly compared to the control, wherein, the former increasing by 38.1% and 40.8%, and the latter increasing by 30.1% and 28.7%, respectively; and the remaining two species declined at different degrees. The water consumption of the four kinds of seedlings declined under the moderate drought stress, and it was minimal under the heavy drought stress. For example, the day-and-night water consumption of P. szechuanica var. tibetica and P. alba under the heavy drought stress was only 25.0% and 19.3% under the normal supply. 2) Under the normal water supply, the diurnal variation of water consumption rate (WCR) of P. szechuanica var. tibetica and S. paraplesia var. subintegra was bimodal curve, with the two peaks at 12:00-14:00 and 16:00-18:00; the other two species was a single peak curve, with the peak at 12:00-14:00. Under the light drought stress, the WCR diurnal variation of P. alba was bimodal curve, the first peak of which was at 12:00-14:00, and the remaining three species were observed a single peak, the peak of P. szechuanica var. tibetica in which was at 12:00-14:00, and the other two species were at 14:00-16:00. Under the moderate drought stress, the WCR diurnal variation of all tree species showed a single peak curve, the peak of P. szechuanica var. tibetica and P. alba in which was at 12:00-14:00, and the other two species appeared at 14:00-16:00. The curves of all species were single peak under the heavy drought stress, all peaks of which appeared at 14:00-16:00.3) The Pn and Tr of P. szechuanica var. tibetica and P. alba declined gradually with the increase of drought stress. The Pn and Tr of S. paraplesia var. subintegra were largest under the light drought stress, while they decreased gradually with the increase of drought stress.
中文关键词	拉萨半干旱河谷 ; 干旱胁迫 ; 乔木树种 ; 耗水 ; 光合特性
英文关键词	semi-arid valley of Lhasa drought stress arbor species water consumption photosynthetic characteristics
语种	中文
国家	中国
收录类别	CSCD
WOS类目	FORESTRY
WOS研究方向	Forestry
CSCD记录号	CSCD:5678204
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/235281
作者单位	西藏大学农牧学院, 林芝, 西藏 860000, 中国
推荐引用方式 GB/T 7714	辛福梅,杨小林,赵垦田,等. 干旱胁迫对拉萨半干旱河谷主要乔木树种幼树耗水及光合特性的影响[J],2016,42(2):199-208.
APA	辛福梅,杨小林,赵垦田,&罗桑卓玛.(2016).干旱胁迫对拉萨半干旱河谷主要乔木树种幼树耗水及光合特性的影响.浙江大学学报. 农业与生命科学版,42(2),199-208.
MLA	辛福梅,et al."干旱胁迫对拉萨半干旱河谷主要乔木树种幼树耗水及光合特性的影响".浙江大学学报. 农业与生命科学版 42.2(2016):199-208.