[1] Recent empirical studies have shown that multi-angle spectral data can be useful for predicting canopy height, but the physical reason for this correlation was not understood. We follow the concept of canopy spectral invariants, specifically escape probability, to gain insight into the observed correlation. Airborne Multi-Angle Imaging Spectrometer (AirMISR) and airborne Laser Vegetation Im...

Abstract: An inflatable cell model of paragrlider’s wing canopy has been investigated in wind tunnel experiments, which is designed to represent the dynamic behaviors of each cell comprising the canopy. Effects of air-intake of paraglider canopy have also been investigated in this study. The improvement of the shape of air intake and pressure distribution from the standpoints of aerodynamics wi...

The ability to simulate the surface energy balance and microclimate within a plant canopy is contingent upon accurate simulation of radiation exchange within the canopy. Accurate radiation simulations require some assumption of leaf angle distribution to compute transmissivity, reflection and scattering of radiation. The ellipsoidal leaf angle density function can very closely approximate real ...

A forest canopy is a complex system with a highly structural multi-scale architecture. Physical based radiative transfer (RT) modelling has been shown to be an effective tool for retrieval of vegetation canopy biochemical/physical characteristics from optical remote sensing data. A high spatial resolution RT through a forest canopy requires several geometrical and structural parameters of trees...

The dependence of vegetation re ectance on sun and sensor geometry can potentially provide information on canopy properties, but also may be a source of unmodelled systematic error in single-angle remote sensing measurements. In this study, we investigated the angular variability of re ectance measurements from the NASA Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), and the resultin...

There are several very accurate methods to determine leaf angles in closed canopies. However, these are generally very time-consuming or require special equipment. Average canopy leaf angles were derived from simple height and blade length measurements. An exponential relationship between the height/length ratio and the average blade leaf angle was used. The method was tested for two grass spec...

A new instrument called a Multiband Vegetation Imager (MVI) (Kucharik et al., 1997), which uses a 16-bit charge-coupled device (CCD) camera and ®lter exchange mechanism to capture 2-band (visible and near-infrared) image pairs of plant canopies, has been used to measure the light distribution over sunlit leaves and indirectly infer leaf area index (LAI), sunlit LAI and leaf angle distribution (...

The variation of the directional reflectance of a vegetative canopy with azimuthal view angle becomes prominent when the canopy is illuminated by the sun at large angles from zenith. An extension of a previous directional reflectance model of vegetative canopies is presented to quantify this effect. The results indicate that the cause of the azimuthal variation can be traced to solar flux illum...