黑河下游影响荒漠河岸胡杨林蒸腾的冠层与大气耦合分析
|
摘要
基于2014年胡杨主要生长季内树形特征、树干液流、环境因子的实际观测数据,利用经验公式,计算了胡杨冠层蒸腾速率、冠层气孔导度与解耦系数的值,分析了其日变化与季节变化特征。结果表明:(1)从日变化趋势来看,解耦系数在早晨和傍晚时较小,中午达到最大值,这主要是由于早晨和傍晚时太阳辐射比较弱、作物气孔开度小,使冠层气孔导度降低造成的;而中午时冠层气孔导度达到全天的最大值,解耦系数值也达到最大。(2)从季节变化趋势来看,解耦系数与冠层气孔导度变化趋势相近,在生长季内均呈先增大后减小,之后略有浮动增大,最后减小的趋势。本研究对影响荒漠河岸胡杨林蒸腾的冠层与下层大气进行相关性推断,认为影响胡杨林蒸腾的冠层与大气耦合度较高。尽管试验地处于极端干旱区,下层大气十分干燥,林冠层叶气界面水分散失很快,但黑河下游河岸林供水良好,林冠层空气动力学条件相近,使得胡杨林蒸腾主要受叶面气孔控制。
The degree of coupling between the plant canopy and atmosphere indicates the exchanging ability of momentum,energy and mass between the two systems. Based on the measured data of tree characteristics,sap flowand environmental factors in 2014 and the empirical formulae,we calculated the transpiration rate,stomatal conductance and decoupling coefficient of the canopy,and analyzed the diurnal and seasonal features of all the three parameters. Results indicated that:( 1) the value of decoupling coefficient peaked at noon and minimized in the morning and evening,and this is mainly due to the weak radiation and lower stomatal conductance in the morning and evening. However,the canopy stomatal conductance peaked at noon,and the value of decoupling coefficient maximized accordingly.( 2) The seasonal variation of the decoupling coefficient is similar to that of the canopy stomatal conductance. It increased at first and then decreased,then increased slightly and decreased at last. We inferred the correlation between the canopy of the Populus euphratica forest and atmosphere,result showed that the canopy of P. euphratic was highly coupled with the atmosphere. Though our study area is located in the Ejin oasis where is extremely dry,the supplement of the surface water from the upstream of Heihe River ensured the water that P. euphratica needed. The water and aerodynamic status are both good,and the transpiration is mainly controlled by stoma.
The degree of coupling between the plant canopy and atmosphere indicates the exchanging ability of momentum,energy and mass between the two systems. Based on the measured data of tree characteristics,sap flowand environmental factors in 2014 and the empirical formulae,we calculated the transpiration rate,stomatal conductance and decoupling coefficient of the canopy,and analyzed the diurnal and seasonal features of all the three parameters. Results indicated that:( 1) the value of decoupling coefficient peaked at noon and minimized in the morning and evening,and this is mainly due to the weak radiation and lower stomatal conductance in the morning and evening. However,the canopy stomatal conductance peaked at noon,and the value of decoupling coefficient maximized accordingly.( 2) The seasonal variation of the decoupling coefficient is similar to that of the canopy stomatal conductance. It increased at first and then decreased,then increased slightly and decreased at last. We inferred the correlation between the canopy of the Populus euphratica forest and atmosphere,result showed that the canopy of P. euphratic was highly coupled with the atmosphere. Though our study area is located in the Ejin oasis where is extremely dry,the supplement of the surface water from the upstream of Heihe River ensured the water that P. euphratica needed. The water and aerodynamic status are both good,and the transpiration is mainly controlled by stoma.
引文
Cienciala E,Kuˇcera J,M almer A,2000.Tree sap flow and stand transpiration of tw o Acacia mangium plantations in Sabah,Borneo[J].J Hydrology,236(1):109-120.
Granier A,Biron P,Lemoine D,2000.Water balance,transpiration and canopy conductance in tw o beech stands[J].Agricultural and Forest M eteorology,100(4):291-308.
Herbst M,1995.Stomatal behaviour in a beech canopy:an analysis of Bow en ratio measurements compared w ith porometer data[J].Plant,Cell Environ,18(9):1010-1018.
Jarvis P G,M c Naughton K,1986.Stomatal control of transpiration:scaling up from leaf to region[J].Adv Ecological Res,15(1):1-49.
Kumagai T O,Saitoh T M,Sato Y,et al,2004.Transpiration,canopy conductance and the decoupling coefficient of a low land mixed dipterocarp forest in Saraw ak,Borneo:dry spell effects[J].J Hydrology,287(1):237-251.
M agnani F,Leonardi S,Tognetti R,et al,1998.M odelling the surface conductance of a broad-leaf canopy:effects of partial decoupling from the atmosphere[J].Plant,Cell Environ,21(8):867-879.
M einzer F,Andrade J,Goldstein G,et al,1997.Control of transpiration from the upper canopy of a tropical forest:the role of stomatal,boundary layer and hydraulic architecture components[J].Plant,Cell Environ,20(10):1242-1252.
M einzer F,Goldstein G,Holbrook N,et al,1993.Stomatal and environmental control of transpiration in a low land tropical forest tree[J].Plant Cell Environ,16(4):429-429.
Sellers P,Dickinson R,Randall D,et al,1997.M odeling the exchanges of energy,w ater,and carbon betw een continents and the atmosphere[J].Science,275(5299):502-509.
Si J H,Feng Q,Zhang X Y,et al,2007.Sap flow of Populus euphratica in a desert riparian forest in an extreme arid region during the grow ing season[J].Journal of Integrative Plant Biology,49(4):425-436.
Steduto P,Hsiao T C,1998.M aize canopies under tw o soil w ater regimes:III.Variation in coupling w ith the atmosphere and the role of leaf area index[J].Agricultural and Forest M eteorology,89(3):201-213.
Wullschleger S D,Wilson K B,Hanson P J,2000.Environmental control of w hole-plant transpiration,canopy conductance and estimates of the decoupling coefficient for large red maple trees[J].Agricultural and Forest M eteorology,104(2):157-168.
白福,李文鹏,李志恒,2008.黑河流域植被退化的主要原因分析[J].干旱区研究,25(2):219-224.Bai F,Li W P,Li Z H,2008.Analysis on the main causes resulting in vegetation degeneration in the Heihe river basin[J].Arid Zone Research,25(2):219-224.
窦军霞,张一平,于贵瑞,等,2007.西双版纳热带季节雨林水热通量[J].生态学报,27(8):3099-3109.Dou J X,Zhang Y P,Yu G R,et al,2007.Inter-annual and seasonal variations of energy and w ater vapour fluxes above a tropical seasonal rain forest in Xishuangbanna,SW China[J].Acta Ecologca Sinica,27(8):3099-3109.
司建华,常宗强,苏永红,等,2008.胡杨叶片气孔导度特征及其对环境因子的响应[J].西北植物学报,28(1):125-130.Si J H,Chang Z Q,Su Y H,et al,2008.Stomatal conductance characteristics of Populus euphratica leaves and response to environmental factors in the extreme arid region[J].Acta Botanica Boreali-Occidentalia Sinica,28(1):125-130.
司建华,冯起,张小由,等,2007.极端干旱区荒漠河岸林胡杨生长季树干液流变化[J].中国沙漠,27(3):442-447.Si J H,Feng Q,Zhang X Y,et al,2007.Sap flow of Populus euphratica in desert riparian forest in extreme arid region during the grow ing season[J].J Desert Res,27(3):442-447.
苏里坦,阿迪力·吐拉尔别克,王兴勇,等,2014.地下变水位条件下塔里木河下游河岸胡杨林蒸腾模型[J].干旱区地理,37(5):916-921.Su L T,Adili T,Wang X Y,et al,2014.Transpiration model of Populous euphratica in the low er reaches of Tarim River under groundw ater fluctuation[J].Arid Land Geograp,37(5):916-921.
苏永红,朱高峰,冯起,等,2008.额济纳荒漠河岸胡杨林叶片气孔导度与微环境因子关系的模拟研究[J].西北植物学报,28(7):1434-1439.Su Y H,Zhu G F,Feng Q,et al,2008.The simulation of leaf stomatal conductance of Populus euphratica in desert riparian forest in Ejin[J].Acta Botanica Boreali-Occidentalia Sinica,28(7):1434-1439.
苏永红,朱高峰,冯起,等,2009.蒸发条件下一维垂向非饱和土壤水分运动的数值模拟---以额济纳荒漠河岸胡杨林为例[J].中国沙漠,29(2):236-240.Su Y H,Zhu G F,Feng Q,et al,2009.Numerical simulation of vertical soil w ater movement in unsaturated soils during evaporation:A case study of desert riparian Populus euphratica forest in Ejin[J].J Desert Res,29(2):236-240.
王根绪,程国栋,2002.干旱内陆流域生态需水量及其估算---以黑河流域为例[J].中国沙漠,22(2):129-134.Wang G X,Cheng G D,2002.Water demand of eco-system and estimate method in arid inland river basins[J].J Desert Res,22(2):129-134.
阳伏林,周广胜,2010.内蒙古温带荒漠草原能量平衡特征及其驱动因子[J].生态学报,30(21):5769-5780.Yang F L,Zhou GS,2010.Characteristics and driving factors of energy budget over a temperate desert steppe in Inner M ongolia[J].Acta Ecologica Sinica,30(21):5769-5780.
张小由,康尔泗,司建华,等,2006.胡杨蒸腾耗水的单木测定与林分转换研究[J].林业科学,42(7):28-32.Zhang X Y,Kang ES,Si J h,et al,2006.Stem sap flow of individual plant of populus euphratica and its conversion to forest w ater consumption[J].Scientia Silvae Sinicae,42(7):28-32.
张永强,刘昌明,2002.农田冠层与大气水汽通量耦合分析[J].河北农业大学学报,25(3):28-32.Zhang Y Q,Liu C M,2002.Coupling analysis of w ater vapour flux betw een canopy and atmosphere in a farmland[J].Journal of Agricultural University of Hebei,25(3):28-32.
Granier A,Biron P,Lemoine D,2000.Water balance,transpiration and canopy conductance in tw o beech stands[J].Agricultural and Forest M eteorology,100(4):291-308.
Herbst M,1995.Stomatal behaviour in a beech canopy:an analysis of Bow en ratio measurements compared w ith porometer data[J].Plant,Cell Environ,18(9):1010-1018.
Jarvis P G,M c Naughton K,1986.Stomatal control of transpiration:scaling up from leaf to region[J].Adv Ecological Res,15(1):1-49.
Kumagai T O,Saitoh T M,Sato Y,et al,2004.Transpiration,canopy conductance and the decoupling coefficient of a low land mixed dipterocarp forest in Saraw ak,Borneo:dry spell effects[J].J Hydrology,287(1):237-251.
M agnani F,Leonardi S,Tognetti R,et al,1998.M odelling the surface conductance of a broad-leaf canopy:effects of partial decoupling from the atmosphere[J].Plant,Cell Environ,21(8):867-879.
M einzer F,Andrade J,Goldstein G,et al,1997.Control of transpiration from the upper canopy of a tropical forest:the role of stomatal,boundary layer and hydraulic architecture components[J].Plant,Cell Environ,20(10):1242-1252.
M einzer F,Goldstein G,Holbrook N,et al,1993.Stomatal and environmental control of transpiration in a low land tropical forest tree[J].Plant Cell Environ,16(4):429-429.
Sellers P,Dickinson R,Randall D,et al,1997.M odeling the exchanges of energy,w ater,and carbon betw een continents and the atmosphere[J].Science,275(5299):502-509.
Si J H,Feng Q,Zhang X Y,et al,2007.Sap flow of Populus euphratica in a desert riparian forest in an extreme arid region during the grow ing season[J].Journal of Integrative Plant Biology,49(4):425-436.
Steduto P,Hsiao T C,1998.M aize canopies under tw o soil w ater regimes:III.Variation in coupling w ith the atmosphere and the role of leaf area index[J].Agricultural and Forest M eteorology,89(3):201-213.
Wullschleger S D,Wilson K B,Hanson P J,2000.Environmental control of w hole-plant transpiration,canopy conductance and estimates of the decoupling coefficient for large red maple trees[J].Agricultural and Forest M eteorology,104(2):157-168.
白福,李文鹏,李志恒,2008.黑河流域植被退化的主要原因分析[J].干旱区研究,25(2):219-224.Bai F,Li W P,Li Z H,2008.Analysis on the main causes resulting in vegetation degeneration in the Heihe river basin[J].Arid Zone Research,25(2):219-224.
窦军霞,张一平,于贵瑞,等,2007.西双版纳热带季节雨林水热通量[J].生态学报,27(8):3099-3109.Dou J X,Zhang Y P,Yu G R,et al,2007.Inter-annual and seasonal variations of energy and w ater vapour fluxes above a tropical seasonal rain forest in Xishuangbanna,SW China[J].Acta Ecologca Sinica,27(8):3099-3109.
司建华,常宗强,苏永红,等,2008.胡杨叶片气孔导度特征及其对环境因子的响应[J].西北植物学报,28(1):125-130.Si J H,Chang Z Q,Su Y H,et al,2008.Stomatal conductance characteristics of Populus euphratica leaves and response to environmental factors in the extreme arid region[J].Acta Botanica Boreali-Occidentalia Sinica,28(1):125-130.
司建华,冯起,张小由,等,2007.极端干旱区荒漠河岸林胡杨生长季树干液流变化[J].中国沙漠,27(3):442-447.Si J H,Feng Q,Zhang X Y,et al,2007.Sap flow of Populus euphratica in desert riparian forest in extreme arid region during the grow ing season[J].J Desert Res,27(3):442-447.
苏里坦,阿迪力·吐拉尔别克,王兴勇,等,2014.地下变水位条件下塔里木河下游河岸胡杨林蒸腾模型[J].干旱区地理,37(5):916-921.Su L T,Adili T,Wang X Y,et al,2014.Transpiration model of Populous euphratica in the low er reaches of Tarim River under groundw ater fluctuation[J].Arid Land Geograp,37(5):916-921.
苏永红,朱高峰,冯起,等,2008.额济纳荒漠河岸胡杨林叶片气孔导度与微环境因子关系的模拟研究[J].西北植物学报,28(7):1434-1439.Su Y H,Zhu G F,Feng Q,et al,2008.The simulation of leaf stomatal conductance of Populus euphratica in desert riparian forest in Ejin[J].Acta Botanica Boreali-Occidentalia Sinica,28(7):1434-1439.
苏永红,朱高峰,冯起,等,2009.蒸发条件下一维垂向非饱和土壤水分运动的数值模拟---以额济纳荒漠河岸胡杨林为例[J].中国沙漠,29(2):236-240.Su Y H,Zhu G F,Feng Q,et al,2009.Numerical simulation of vertical soil w ater movement in unsaturated soils during evaporation:A case study of desert riparian Populus euphratica forest in Ejin[J].J Desert Res,29(2):236-240.
王根绪,程国栋,2002.干旱内陆流域生态需水量及其估算---以黑河流域为例[J].中国沙漠,22(2):129-134.Wang G X,Cheng G D,2002.Water demand of eco-system and estimate method in arid inland river basins[J].J Desert Res,22(2):129-134.
阳伏林,周广胜,2010.内蒙古温带荒漠草原能量平衡特征及其驱动因子[J].生态学报,30(21):5769-5780.Yang F L,Zhou GS,2010.Characteristics and driving factors of energy budget over a temperate desert steppe in Inner M ongolia[J].Acta Ecologica Sinica,30(21):5769-5780.
张小由,康尔泗,司建华,等,2006.胡杨蒸腾耗水的单木测定与林分转换研究[J].林业科学,42(7):28-32.Zhang X Y,Kang ES,Si J h,et al,2006.Stem sap flow of individual plant of populus euphratica and its conversion to forest w ater consumption[J].Scientia Silvae Sinicae,42(7):28-32.
张永强,刘昌明,2002.农田冠层与大气水汽通量耦合分析[J].河北农业大学学报,25(3):28-32.Zhang Y Q,Liu C M,2002.Coupling analysis of w ater vapour flux betw een canopy and atmosphere in a farmland[J].Journal of Agricultural University of Hebei,25(3):28-32.