《植物生理学报》 2013, 49(12): 1385-1392

不同水分条件下盆栽苹果树蒸腾速率动态模拟

高照全^1,*, 李志强¹, 陈吉虎²

¹北京农业职业学院, 北京102442; ²水利部水土保持监测中心, 北京100055

通信作者：高照全；E-mail: gaozhaoquan@sina.com；Tel: 010-80358899

摘　要：

土壤水分是制约作物产量和品质的主要环境因素之一, 估算不同水分条件下的蒸腾速率(Tr)对于作物的优质高产和节水灌溉等具有十分重要的意义。通过构建蒸腾-气孔-光合耦合模型可模拟出不同水分条件下苹果树的蒸腾动态, 模型参数根据逐步干旱条件下盆栽‘富士’苹果树试验获取。结果表明, Tr主要由饱合水气压差和气孔导度(Gs)驱动, 同时气象因子和土壤水势对其有强烈的交互作用影响。Tr随土壤水势的下降而减小, 当土壤水势低于−0.4 MPa时减小幅度更加显著。晴天时, Gs在一天中呈双峰曲线, 而Tr呈单峰曲线, 最大值出现在13:00左右, 约为3.6 mmol·m^-2·s^-1。根据该模型可计算出不同水分条件下1株盆栽苹果树(总叶片积为0.26 m^-2)全天的蒸腾总量, 供水充足时为652.1 g, 严重干旱时(土壤水势为−1.5 MPa)为85.4 g。实测值和模拟值的比较表明, 该耦合模型能够模拟出不同土壤水分条件下盆栽苹果树的蒸腾动态以及土壤的含水量。

关键词：苹果; 干旱; 蒸腾作用; 模型; 小气候; 气孔导度

收稿：2013-07-29   修定：2013-10-28

资助：科技部星火计划(2008GA600009)和北京农业职业学院院级项目(XY-BS-12-2和XY-YF-13-02)

Dynamic Simulation of Transpiration Rates of Potted Apple (Malus domestica) Trees under Different Water Condition

GAO Zhao-Quan^1,*, LI Zhi-Qiang¹, Chen Ji-Hu²

¹Beijing Vocational College of Agriculture, Beijing 102442, China;²Monitoring Center of Soil and Water Conservation of Ministry of Water Resources, Beijing 100055, China

Corresponding author: GAO Zhao-Quan; E-mail: gaozhaoquan@sina.com; Tel: 010-80358899

Abstract:

Plants are often subjected to periods of soil water deficits during life cycle. To predict transpiration rates (Tr) of drought is very important applications in many area including agricultural production and irrigation. A coupled model of transpiration, stomatal conductance, and photosynthesis was presented for the simulation of transpiration rate in apple trees under different water condition. The paramaters of this model was estimated by the eaperiment of potted apple trees (Malus domestica Borkh. cv. ‘Fuji’) under gradully drought. The results showed that Tr was driven mainly by vapor pressure deficit and stomatal conductance (Gs), and strong interactions among various microclimatic factors and soil water potential. Tr consistently decreased with the decrease in soil water potential, and decreased rapidly when soil water potential was below −0.4 MPa. It could be seen that the diurnal course of Gs on clear days was a double-peak curve. But the diurnal course of Tr reached one peak around 13:00 o’clock and the maximum was about 3.6 mmol·m^-2·s^-1 on clear day. On the basis of this model, we predicted that during a whole day a potted apple tree with leaf area of 0.26 m² would lose 652.1 g of H₂O when soil water was not limited and lost 85.4 g of H₂O when soil water potential was about −1.8 MPa. Comparison among simulated and measured values indicated that the coupled model was able to simulate the changes in soil water cotents as well as the changes in transpiration rates of potted apple tree under different soil water deficits.

Key words: apple (Malus domestica); drought; transpiration; model; microclimatic; stomatal conductance