GREENSPAN茎流法测定茄子植株蒸腾的有效性分析

用快速称重法、Penman-Monteith微气象法(简称P-M法)与GREENSPAN茎流法在晴天或阴天同步测定盆栽茄子植株的蒸腾速率，验证GREENSPAN茎流法在测量作物蒸腾方面的精度及有效性。结果表明，GREENSPAN茎流法具有与称重法、P-M法相似的测试效果，可以较灵敏地反映不同天气状况下作物蒸腾量的变化规律。与称重法、P-M法相比，GREENSPAN茎流法测值相对误差分别为1．07％～12．78％和0．5％～19．1％，绝对误差分别为每株0．13～1．56g／h和0．08～2．20g／h。GREENSPAN茎流法与称重法、P-M法的测值均呈极显著直线相关，相关关系式分别为SP-0．9778QW和SP=0．9896PW，R^2系数分别为0．9476和0．9391。GREENSPAN茎流法在定量研究作物蒸腾方面具有较高的精度和适用性，GREENSPAN茎流法为大田作物蒸腾测定提供了一个新方法。

Accuracy and Validation of Eggplant Transpiration Measured by GREENSPAN Method

The accuracy and the validation of crop transpiration measured with sap flow by GREENSPAN technique were evaluated through pot experiment and theory calculation.The results showed that GREENSPAN method has the same result as the weighing and P-M.It could measure effectively the transpiration rate of eggplant plant and reflect sensitively the change regular of crop transpiration under the conditions of different weather status as the weighing method and Penman-Monteith method.The relative errors of measured values by GREENSPAN technique were 1.07%~12.78% and 0.5%~19.1% respectively compared with values through weighing and Penman-Monteith methods,and the absolute errors were 0.13~1.56 g·plant^-1·h^-1 and 0.08~2.20g·plant^-1·h^-1 respectively.The GREENSPAN transpiration values were significantly linear correlation with values by weighing method and Penman-Monteith method,and the correlation coefficient was more than 0.9.In conclusion,the GREENSPAN method could be considered as a valuable method because of its higher accuracy and applicability in measuring transpiration of certain crop plants.This method would be improved to measure crop transpiration in the field.