Leaf Surface Roughness Research Articles

Transmission, reflection, and depolarization of an optical wave for a single leaf

Optical scattering by a single leaf is investigated, taking into account the structures inside a leaf and the leaf surface roughness. An optical scattering model, which includes both volume scattering and rough surface scattering, is developed using vector radiative transfer theory and Kirchhoff rough surface scattering theory. A leaf is modeled as a slab of water with an irregular surface containing randomly distributed spherical particles. The degree of polarization and the normalized scattering cross section per unit area for the transmitted and reflected copolarized and cross-polarized intensities are obtained for corn, potato, and laurel leaves. The theoretical results are compared with measured data to determine the parameters for the scatterers inside the leaf, the surface roughness, and the optical thickness. The agreement between the calculation and experiment for a wide variety of cases shows that this is a reasonable leaf model in the optical frequency regime.

Transmission, reflection, and depolarization of an optical wave for a single leaf

Optical scattering by a single leaf is investigated, taking into account the structures inside a leaf and the leaf surface roughness. An optical scattering model, which includes both volume scattering and rough surface scattering, is developed using vector radiative transfer theory and Kirchhoff rough surface scattering theory. A leaf is modeled as a slab of water with an irregular surface containing randomly distributed spherical particles. The degree of polarization and the normalized scattering cross section per unit area for the transmitted and reflected copolarized and cross-polarized intensities are obtained for corn, potato, and laurel leaves. The theoretical results are compared with measured data to determine the parameters for the scatterers inside the leaf, the surface roughness, and the optical thickness. The agreement between the calculation and experiment for a wide variety of cases shows that this is a reasonable leaf model in the optical frequency regime.

The influence of leaf surface roughness on the spreading of oil spray drops

SUMMARYThe effect of surface roughness of leaves on the retention and spreading of oil drops is considered. Three types of roughness have been recognized. Leaf hairs and protruding or recessed veins underlying the cuticle constitute a macroscopic roughness. Microscopic roughness is determined by epidermal cell size and arrangement, which influence the geometry of the grooves between these cells. Ultra‐microscopic roughness is determined by the size, shape and organization of the epicuticular wax system. The effect of environmental conditions on surface roughness is also considered and the significance of the spreading of spray drops is discussed in relation to the application of pesticides.