Granier’s probes were applied to measure the sap flow of 14 sample trees in an Acacia mangium forest on the hilly lands in Heshan City, Guangdong, during the time period of October, 2003. The photosynthetically active radiation (PAR), air relative humidity (RH) and temperature of air (T) above the forest canopy were recorded. The sap flow measurement was used in combination with morphological characteristics of tree and forest structure to calculate the whole-tree transpiration (E), stand transpiration (Et), and mean canopy stomatal conductance (gc). Analyses on the relationships between tree morphological characters and whole-tree water use, and on the responses of gc to PAR and vapor pressure deficit (D) were conducted. The results showed that whole-tree transpiration correlated significantly and positively with tree diameter at breast height (DBH) (p < 0.0001), with sapwood area (p < 0.0001), and with canopy size (p = 0.0007) logarithmically, but exponentially with tree height (p = 0.014). The analyses on the responses of canopy stomatal conductance showed that the maximum gc (gcmax) changed with PAR in a hyperbolic curve (p < 0.0001) and with D in a logarithmic one (p < 0.0001). The results obtained with sap flow technique indicate its reliability and accuracy of the methods of estimation of whole-tree and stand transpirations and canopy stomatal conductance.
LIU Xiaojing, ZHAO Ping, RAO Xingquan, MA Ling, CAI Xi'an, ZENG Xiaoping
. Response of canopy stomatal conductance of forest to environmental driving
factors[J]. Frontiers of Forestry in China, 2008
, 3(1)
: 64
-71
.
DOI: 10.1007/s11461-008-0001-3
1. Deng H P Wu Z F Zhou D W 2000 Response of broad-leaved Pinus koraiensis forest in Xiao Xing An LingMt to global climate change-a dynamic modelingChin J App Ecol114346(in Chinese)
2. Granier A 1987 Evaluation of transpiration in a Douglas-fir stand by meansof sap flow measurementsTree Phys3309319
3. Granier A Biron P Köstner B Gay L W Najjar G 1996 Comparison of xylem sapflow and water vapor flux at the stand level and derivation of canopyconductance forest Scots pineTheor ApplClimatol53115122. doi:10.1007/BF00866416
4. Granier A Bréda N 1996 Modeling canopyconductance and stand transpiration of an oak forest from sap flowmeasurementsAnn Sci For53537546. doi:10.1051/forest:19960233
5. Köstner B Schulze E D Kelliher F M 1992 Transpiration and canopy conductance ina pristine broad-leaved forest of Nothofagus: An analysis of xylemsap flow and eddy correlation measurementsOecologia91350359. doi:10.1007/BF00317623
6. Kubota M Tenhunnen J Zimmermann R Schmidt M Adiku Samuel Kakubari Y 2005 Influences of environmental factors on the radial profileof sap flux density in Fagus crenata growing at different elevations in the Naeba Mountains, JapanTree Phys25545556
7. Lu P Urban L Zhao P 2004 Granier's thermal dissipation probe (TDP)method for measuring sap flow in trees: Theory and practiceActa Bot Sin46(6)631646
8. Ma L Zhao P Rao X Q Cai X A Zeng X P 2005 Main determination methodsof tree transpirationChin J App Ecol24(1)8896(in Chinese)
9. Pataki D E Oren R Katul G Sigmon J 1998 Canopy conductance of Pinus taeda, Liquidambar styraciflua and Quercus phello under varying atmosphericand soil water conditionsTree Phys18307315
10. Running S W Coughlan J C 1988 A generalmodel of forest ecosystem processes for regional application. I. Hydrologicbalance, canopy gas exchange and primary production processEcol Model42125154. doi:10.1016/0304‐3800(88)90112‐3
11. Schäfer K V R Oren R Tenhunen J D 2000 The effect of tree height on crown levelstomatal conductancePlant Cell Environ23365375. doi:10.1046/j.1365‐3040.2000.00553.x
12. Schulze E D 1986 Carbon dioxide and water vapor exchange in response todrought in the atmosphere and in the soilAnn Rev Plant Phys37247274. doi:10.1146/annurev.pp.37.060186.001335
13. Sun G C Zhao P Zeng X P Peng S L 2001 Influence of elevated atmospheric CO2 concentrationon photosynthetic and leaf nitrogen concentration partition in processof photosynthetic carbon cycles in Musa paradisiaceaChin J App Ecol12429434(in Chinese)
14. Sun G C Zhao P Zeng X P Peng S L 2004 Variation of photosynthetic parameters in CO2 acclimation of Citrus grandis leavesChin J App Ecol15914(in Chinese)
15. Zeng X P Peng S L Zhao P 2000a Measurement of respiration amount inartificial Acacia mangium forestin a low subtropical hill forest region of GuangdongActa Phytoecol Sin24(4)420424(in Chinese)
16. Zeng X P Zhao P Peng S L 1999 Study on the water ecology of three understoryplants in a leguminous mixed forest in Heshan, GuangdongEcol Sci18(4)15(in Chinese)
17. Zeng X P Zhao P Peng S L 2000b Study on the water ecology of artificial Acacia mangium forest in the Heshan hillyregion, Guangdong ProvinceActa PhytoecolSin24(1)6973(in Chinese)
18. Zhao P 2003 Advance in plant ecophysiological studies on revegetationof degraded ecosystemsChin J App Ecol14(11)20312036(in Chinese)
19. Zhao P Peng S L 2001 Species andspecies diversity in relation with restoration and persistence ofdegraded ecosystem functionChin J App Ecol12(1)132136(in Chinese)
20. Zhao P Zeng X P Cai X A Peng S L 2002 Report on measurement of leaf area index of low subtropical forestsby using digital plant canopy imagerGuihaia22(6)485489(in Chinese)
21. Zhao P Zeng X P Peng S L 2003 Ecological adaptation of leaf gas exchangeof trees used for re-vegetation under different experimental lightregimesChin J Ecol22(3)18(in Chinese)
22. Zhao P Zeng X P Yu Z Y 1997 Relationship between transpiration ofshrubs under artificial Acacia mangium stand on hilly land of South China and its microclimate during wetseasonChin J App Ecol8(4)365371(in Chinese)
