CONTRASTING WATER USE STRATEGY OF CO-OCCURRING PINUS-QUERCUS TREES IN THREE GORGES RESERVOIR

doi:10.17521/cjpe.2006.0008

Abstract

Abstract:

With the rise of water level, the construction of the Three-Gorges Dam may have significant impacts on plant carbon-water relation and ecosystem properties in this region. To understand how the plants in this region adapt to the changes in water environments, we measured gas exchange, water potential and δ ¹³C of sapling and mature trees of three co-occurring coniferous and deciduous species: Pinus massoniana, Quercus variabilis and Q. aliena, all are dominant tree species in this region. The two deciduous broad-leaf trees (Q. variabilis and Q. aliena) exhibited higher photosynthetic (P_n) and stomatal conductance (G_s) than the evergreen conifer species (P. massoniana). The predawn water potential (ψ_pd) of P. massoniana was lower than that of the two broad-leaf species. Intrinsic water use efficiency (WUE_i, P_n/G_s) of P. massoniana was higher than those of Q. variabilis and Q. aliena. However, the differences in carbon isotope ratio (δ¹³C) of leaves among species, which gives integrative information of WUE in growing season period, were not statistically significant. We also compared eco-physiological parameters between saplings and mature trees of these three species. The P_n and G_s values of the mature trees were significantly lower than those of the saplings. The mature trees showed lower ψ_pd value, but the difference between the mature trees and the saplings was not statistically significant. However, the WUE_i values of all mature trees were significantly higher than those of the saplings. The δ¹³C values of mature trees showed more positive than those of corresponding saplings, indicating also higher WUE in the mature trees. From these results, we concluded that 1) P. massoniana showed different water use strategies from two Quercus trees species, and 2) the mature trees of these three dominant tree species showed lower photosynthetic rate but higher WUE than those of their corresponding saplings.

Key words: Three Gorges, Pinus-Quercus community, Water use efficiency, Water potential, Carbon isotope ratio

SUN Shuang-Feng, HUANG Jian-Hui, LIN Guang-Hui, HAN Xing-Guo. CONTRASTING WATER USE STRATEGY OF CO-OCCURRING PINUS-QUERCUS TREES IN THREE GORGES RESERVOIR[J]. Chin J Plant Ecol, 2006, 30(1): 57-63.

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URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2006.0008

https://www.plant-ecology.com/EN/Y2006/V30/I1/57

Figures/Tables 3

Fig.1 Photosynthesis, stomatal conductance and intrinsic water use efficiency of mature and sapling of the three species (Means±SE) Different capitals indicate significant difference among mature trees, while different small letters show significant difference among saplings. * indicates the values between the same mature and sapling species is significant (p<0.05)

Table 1 Predawn leaf water potential values (ψpd, MPa) (Mean±SE) and midday leaf water potentials (ψmd, MPa) of the three species in different age classes (Mean±SE)

生长阶段 Age class	物种 Species	清晨水势ψ_pd	中午水势ψ_md	ψ_pd-ψ_md
成年树Mature	马尾松Pinus massoniana	-0.39±0.09^A	-1.11±0.10^A	0.72
	槲栎 Quercus aliena	-0.24±0.02^A	-2.34±0.17^B	2.10
	栓皮栎Q. variabilis	-0.23±0.06^A	-2.49±0.18^B	2.25
幼树 Sapling	马尾松Pinus massoniana	-0.31±0.01^a	-0.97±0.08^a	0.67
	槲栎 Quercus aliena	-0.19±0.03^b	-1.52±0.17^b*	1.33
	栓皮栎Q. variabilis	-0.13±0.04^b	-2.66±0.08^c	2.53

Fig.2 Foliar δP13PC of mature and saplings of the three species (Mean±SE) Different capitals indicate significant difference among mature trees, while different small letters show significant difference among saplings. * indicates the values between the same mature and sapling species is significant (p<0.05)

References 32

[1]	Andrade JL, Meinzer FC, Goldstein G, Holbrook NM, Cavelier J, Jackson P, Silvera K (1998). Regulation of water flux through trunks, branches, and leaves in trees of a lowland tropical forest. Oecologia, 115,463-471. DOI URL PMID
[2]	Becker P, Meinzer FC, Wullschleger SD (2000). Hydraulic limitation of tree height: a critique. Functional Ecology, 14,4-11.
[3]	Bloom AJ, Chapin FS Ш, Mooney HA (1985). Resource limitation in plants — an economic analogy. Annual Review of Ecology and Systematics, 16,363-392.
[4]	Bond BJ, Kavanagh KL (1999). Stomatal behavior of four woody species in relation to leaf-specific hydraulic conductance and threshold water potential. Tree Physiology, 19,503-510. DOI URL PMID
[5]	Bond WJ (1989). The tortoise and the hare: ecology of angiosperm dominance and gymnosperm persistence. Biological Journal of the Linnean Society, 36,227-249.
[6]	Castell C, Terradas J, Tenhunen JD (1994). Water relations, gas exchange, and growth of resprouts and mature plant shoots of Arbutus unedo L. & Quercus ilex L. Oecologia, 98,201-211. DOI URL PMID
[7]	Cavender-Bares J, Bazzaz FA (2000). Changes in drought response strategies with ontogeny in Quercus rubra: implications for scaling from seedlings to mature trees. Oecologia, 124,8-18.
[8]	Chapin FS Ш, Schulze ED, Mooney HA (1990). The ecology and economics of storage in plants. Annual Review of Ecology and Systematics, 21,423-447.
[9]	Chen WL (陈伟烈), Zhang XQ (张喜群), Liang SY (梁松筠), Jin YX (金义兴), Yang QX (杨启修) (1994). Plants and Composite Agricultural Ecosystems of the Three Gorges Reservoir Region (三峡库区的植物与复合农业生态系统). Science Press, Beijing. (in Chinese)
[10]	Cheng RM (程瑞梅), Xiao WF (肖文发), Li JW (李建文), Ma J (马娟), Han JJ (韩景军) (2002). Analysis on forest plant diversity in the Three Gorges Reservoir Area. Chinese Journal of Applied Ecology (应用生态学报), 13,35-40. (in Chinese with English abstract)
[11]	Damesin C, Rambal S (1995). Field study of leaf photosynthetic performance by a Mediterranean deciduous oak tree ( Quercus pubescens) during a severe summer drought. New Phytologist, 131,159-167.
[12]	Dawson TE, Mambelli S, Plamboeck AH, Templer PH, Tu KP (2002). Stable isotopes in plant ecology. Annual Review of Ecology and Systematics, 33,507-559.
[13]	Donovan LA, Ehleringer JR (1991). Ecophysiological differences among juvenile and reproductive plants of several woody species. Oecologia, 86,594-597. DOI URL PMID
[14]	Farquhar GD, O'Leary MH, Berry JA (1982). On the relationship between carbon isotope discrimination and the intercellular carbon dioxide concentration in leaves. Australian Journal of Plant Physiology, 9,121-137.
[15]	Hubbard RM, Bond BJ, Ryan MG (1999). Evidence that hydraulic conductance limits photosynthesis in old Pinus ponderosa trees. Tree Physiology, 19,165-172. DOI URL PMID
[16]	Kolb TE, Stone JE (2000). Differences in leaf gas exchange and water relations among species and tree sizes in an Arizona pine-oak forest. Tree Physiology, 20,1-12. DOI URL PMID
[17]	Levitt J (1980). Responses of Plants to Environmental Stresses. Academic Press, NewYork.
[18]	Llorens L, Penuelas J, Filella I (2003). Diurnal and seasonal variations in the photosynthetic performance and water relations of two co-occurring Mediterranean shrubs, Erica multiflora and Globularia alypum. Physiologia Plantarum, 118,84-95. DOI URL PMID
[19]	Martinez-Vilalta J, Sala A, Pinol J (2004). The hydraulic architecture of Pinaceae — a review. Plant Ecology, 171,3-13.
[20]	McDowell NG, Phillips N, Lunch C, Bond BJ, Ryan MG (2002). An investigation of hydraulic limitation and compensation in large, old Douglas-fir trees. Tree Physiology, 22,763-774.
[21]	Mediavilla S, Escudero A (2003). Mature trees versus seedlings: differences in leaf traits and gas exchange patterns in three co-occurring Mediterranean oaks. Annals of Forest Science, 60,455-460.
[22]	Mediavilla S, Escudero A (2004). Stomatal responses to drought of mature trees and seedlings of two co-occurring Mediterranean oaks. Forest Ecology and Management, 187,281-294.
[23]	Mencuccini M, Grace J (1996). Developmental patterns of above-ground hydraulic conductance in a Scots pine ( Pinus sylvestris L.) age sequence. Plant, Cell and Environment, 19,939-948.
[24]	Mencuccini M, Grace J, Fioravanti M (1997). Biomechanical and hydraulic determinants of tree structure in Scots pine: anatomical characteristics. Tree Physiology, 17,105-13. DOI URL PMID
[25]	Phillips NG, Ryan MG, Bond BJ, McDowell NG, Hinckley TM, Cermak J (2003). Reliance on stored water increases with tree size in three species in the Pacific Northwest. Tree Physiology, 23,237-245. DOI URL PMID
[26]	Ryan MG, Yoder BJ (1997). Hydraulic limits to tree height and tree growth. BioScience, 47,235-242. DOI URL
[27]	Sperry JS, Hacke UG, Oren R, Comstock JP (2002). Water deficits and hydraulic limits to leaf water supply. Plant, Cell and Environment, 25,251-263. URL PMID
[28]	Stout DH, Sala A (2003). Xylem vulnerability to cavitation in Pseudotsuga menziesii and Pinus ponderosa from contrasting habitats. Tree Physiology, 23,43-50. DOI URL PMID
[29]	Walcroft AS, Silvester WB, Grace JC, Carson SD, Waring RH (1996). Effects of branch length on carbon isotope discrimination in Pinus radiata. Tree Physiology, 16,281-286. URL PMID
[30]	Warren CR, Adams AM (2000). Water availability and branch length determine δ ¹³C in foliage of Pinus pinaster. Tree Physiology, 20,637-643. URL PMID
[31]	Wu JG, Huang JH, Han XG, Xie ZQ, Gao XM (2003). Three-Gorges Dam—experiment in habitat fragmentation? Science, 300,1239-1240. DOI URL PMID
[32]	Yang WQ, Murthy R, King P, Topa MA (2002). Diurnal changes in gas exchange and carbon partitioning in needles of fast- and slow-growing families of loblolly pine (Pinus taeda). Tree Physiology, 22,489-498. URL PMID