植物叶组织弹性模量新的计算方法

New Calculation methods of Elastic Modulus in Plant Leaf Tissue

总结了以往几种植物组织总体体积弹性模量ε的计算方法，并推导出另外两种新的计算弹性模暑的公式。用各公式对几个树种各自的同一条ＰＶ曲线的数据计算出ε值，结果表明，同一组数据用不同公式计算的弹性模量的值不相同，有的差异很大。文章初步讨论了不同的公式产生误差的原因。根据数学推导过程我们认为新公式最准确．

In the former research work there were various methods for the calcula-tion of bulk modulus of elasticity in plant leaf tissue. This article puts forward two newequations for their calculation. In fact these two equations are difference form of defini-tion(1).Undoubtedly the error ofεo is the largest one among the three types of relativeerrors of εSWF. εRWC and εo through quantitative calculation of these equations. It is thesum of the relative errors of εSWF and εRWC. From Figure 1,which describes the relation-ship of εg, εSWF,εRWC and εo with turgor ψP, it is clear that when the content of apoplasticwater is not negligible, the error of εRWC is the second largest one and the error of εSWF isthe minimum. The values of εo and εRWC can not reflect the elasticity of plant tissue athigh values of Ra.