干旱区生态环境知识资源中心(Arid): How trees thrive in a dry climate: diurnal and seasonal hydrology and water relations in a riparian cottonwood grove

Arid

DOI	10.1093/treephys/tpab087
	How trees thrive in a dry climate: diurnal and seasonal hydrology and water relations in a riparian cottonwood grove
	Phelan, Colleen A.; Pearce, David W.; Franks, Carmen G.; Zimmerman, Oscar; Tyree, Melvin T.; Rood, Stewart B.
通讯作者	Rood, SB (corresponding author)，Univ Lethbridge, Dept Biol Sci, 4401 Univ Dr W, Lethbridge, AB T1K 3M4, Canada.
来源期刊	TREE PHYSIOLOGY
ISSN	0829-318X
EISSN	1758-4469
出版年	2022
卷号	42 期号:1
英文摘要	In semi-arid ecoregions, trees are restricted to river valley floodplains where river water supplements the limited precipitation. To characterize the associated diurnal and seasonal dynamics in hydrology and water relations, we studied narrowleaf cottonwoods (Populus angustifolia) along a prairie river in Canada. From June through August, the shallow soil moisture was depleted but moisture remained higher above the alluvial groundwater table, which dropped to 2.3 m along with river recession. Throughout the summer, with the daily rise in temperature and insolation, foliar stomatal conductance (g(s)) and transpiration (E) increased to midday and then fell, thus maintaining the midday leaf water potential (Psi(md)) above similar to-1.7 MPa. This Psi(md) approximated the water potential associated with 12% loss of xylem conductivity due to cavitation for branches (P-12); the Psi(md) and P-12 varied independently across eight trees, providing differences in relative hydraulic risk. Sap flux density (F-d) was measured with thermal dissipation probes, and revealed diurnal patterns similar to foliar E. In contrast to our expectation, the daily F-d maxima were consistent through the summer despite the seasonal recession in water supply. Canopy conductances (G(S)), derived from F-d, sapwood area and canopy area, declined with vapor pressure deficit (D) and fell slightly in late summer along with stomatal sensitivity, which reflects the magnitude of decrease in G(S) with increasing D. For spatial up-scaling, satellite-derived near-infrared reflectance of vegetation revealed the woodland phenology, with leaf expansion from May through June and gradual decline in photosynthetic productivity through the summer. Thus, the phreatophytic cottonwoods: (i) sustained substantial water use and productivity through the warm and dry summer, by (ii) accessing shallow soil moisture and then deeper alluvial groundwater, and (iii) providing diurnal stomatal regulation, to (iv) avoid xylem cavitation and (v) maintain fairly constant hydraulic conductance.
英文关键词	groundwater Populus angustifolia sap flow stomatal conductance water potential xylem cavitation
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000745663100009
WOS关键词	DROUGHT-INDUCED CAVITATION ; SAP FLOW ; VAPOR-PRESSURE ; SOIL-WATER ; STOMATAL CONDUCTANCE ; POPULUS-TRICHOCARPA ; EDDY COVARIANCE ; GAS-EXCHANGE ; OLDMAN RIVER ; SAPWOOD AREA
WOS类目	Forestry
WOS研究方向	Forestry
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/376963
作者单位	[Phelan, Colleen A.; Pearce, David W.; Franks, Carmen G.; Zimmerman, Oscar; Rood, Stewart B.] Univ Lethbridge, Dept Biol Sci, 4401 Univ Dr W, Lethbridge, AB T1K 3M4, Canada; [Tyree, Melvin T.] Zhejiang Normal Univ, Coll Chem & Life Sci, Environm Sci, 688 Yingbin Rd, Jinhua 321004, Zhejiang, Peoples R China
推荐引用方式 GB/T 7714	Phelan, Colleen A.,Pearce, David W.,Franks, Carmen G.,et al. How trees thrive in a dry climate: diurnal and seasonal hydrology and water relations in a riparian cottonwood grove[J],2022,42(1).
APA	Phelan, Colleen A.,Pearce, David W.,Franks, Carmen G.,Zimmerman, Oscar,Tyree, Melvin T.,&Rood, Stewart B..(2022).How trees thrive in a dry climate: diurnal and seasonal hydrology and water relations in a riparian cottonwood grove.TREE PHYSIOLOGY,42(1).
MLA	Phelan, Colleen A.,et al."How trees thrive in a dry climate: diurnal and seasonal hydrology and water relations in a riparian cottonwood grove".TREE PHYSIOLOGY 42.1(2022).