果粮复合系统中单株苹果蒸腾需水量的计算

Estimation Transpiration-water Requirement from An Apple Tree in Apple crop Intercropping System

利用单株苹果 (树 )蒸腾计算的修正模式 ,计算了果粮系统中的单株苹果 (树 )日蒸腾需水量 ,同时利用 L I- 160 0稳态气孔仪进行实测 ,结果表明 :计算值与实测值吻合效果较好 ( R2 =0 .9664 ) ,平均相对误差为 7.93 % ;蒸腾需水量与饱和水汽压差和叶面积指数的乘积、水面蒸发和叶面积指数的乘积均具有很好的相关关系 ;建立了以日水面蒸发和叶面积指数为自变量的蒸腾需水量经验模式 ,并利用该经验模式逐日计算了 1998年 4月 1日至 6月 4日单株苹果的蒸腾需水量 ,日平均值为 4 .62 mm· d-1。

The daily transpiration water requirement(TR)from an apple tree in Apple crop intercropping system was estimated using the modified model of transpiration from an apple tree (Thorpe,1978),and measured by LI 1600 steady state porometer.The main results were as follows:(1) The estimated value tallies well with the measured (R 2=0 966 4),and the average relative error between them was 7 93%.(2) Both EV×LAI and D×LAI tally with TR (EV:water surface evaporation;D:saturation pressure deficit of air; LAI:leaf area index per one tree);(3)A empirical model about TR and EV×LAI was developed,and the averaged TR was 5 546 mm·d -1 from April 1 to June 4 in 1998 according to the empirical model.