Jördens C, Scheller M, Breitenstein B, Selmar D, Koch M
Institut für Hochfrequenztechnik, TU Braunschweig, 38106 Braunschweig, Germany.
J Biol Phys. 2009 Aug;35(3):255-64. doi: 10.1007/s10867-009-9161-0. Epub 2009 Jun 11.
We present an electromagnetic model of plant leaves which describes their permittivity at terahertz frequencies. The complex permittivity is investigated as a function of the water content of the leaf. Our measurements on coffee leaves (Coffea arabica L.) demonstrate that the dielectric material parameters can be employed to determine the leaf water status and, therefore, to monitor drought stress in plant leaves. The electromagnetic model consists of an effective medium theory, which is implemented by a third order extension of the Landau, Lifshitz, Looyenga model. The influence of scattering becomes important at higher frequencies and is modeled by a Rayleigh roughness factor.
我们提出了一种植物叶片的电磁模型，该模型描述了其在太赫兹频率下的介电常数。研究了复介电常数随叶片含水量的变化情况。我们对咖啡叶片（阿拉伯咖啡）的测量表明，介电材料参数可用于确定叶片的水分状况，从而监测植物叶片的干旱胁迫。该电磁模型由有效介质理论组成，通过朗道、利夫希茨、洛伊enga模型的三阶扩展来实现。在较高频率下，散射的影响变得很重要，并通过瑞利粗糙度因子进行建模。
