Remote sensing imagery is being used intensively to estimate the biochemical content of vegetation (e.g., chlorophyll, nitrogen, and lignin) at the leaf level. As a result of our need for vegetation biochemical information and our increasing ability to obtain canopy spectral data, a few techniques have been explored to scale leaf-level biochemical content to the canopy level for forests and cro...

remote sensing and aerial photographs are used to produce medium to small scale images. however, for detailed information especially to estimate rangeland vegetation canopy cover there is a need to larger scale images. it is therefore necessary to study the technical applicability of different devices such as short range light airplanes, kites, gliders and balloons. in this research, we focused...

to detection of suitable sampling method to study tree canopy cover in the northern zagros forest, baneeh region forest, kurdistan province, and west of iran was selected. 40 square sample plots one hectare (100×100 m) were selected and perfect inventoried. in every sample plot the position of tree, kind of species and two diameter of crown (m) were recorded. to study of canopy cover different ...

A multi-layer ozone (O3) dry deposition model has been implemented into SOSAA (a model to Simulate the concen-trations of Organic vapours, Sulphuric Acid and Aerosols) to improve the representation of O3 concentration and flux withinand above the forest canopy in the planetary boundary layer. We aim to predict the O3 uptake by a boreal forest canopy undervarying environmental condit...

As optical remote sensing techniques provide increasingly detailed canopy reflectance data at a variety of illumination/view geometries, direct quantitative comparisons between data sets require a flexible model of the bidirectional reflectance distribution function (BRDF) suitable for inversion. Typically, such derivations rely on:1) complex and computationally expensive empirical canopy descr...

We measured gas exchange and various leaf parameters of ash (Fraxinus angustifolia Vahl.) and oak (Quercus robur L.) in the high canopy and of lime (Tilia cordata Mill.) in the lower canopy of a planted, 120-year-old floodplain forest in southern Moravia, Czech Republic. The high-canopy leaves of F. angustifolia and Q. robur had nitrogen concentrations on a leaf area basis (N(area)) that were t...

Coarse woody debris (CWD) and canopy gaps are thought to be important structural components that influence forest ecosystem processes, yet few studies have assessed whether these features interact to influence decay dynamics, and we know of none that does so under controlled experimental canopy gap conditions. By manipulating forest structure to create canopy openings, we tested whether canopy ...

A new nonlinear analytical model for canopy flow over gentle hills is presented. This model is established based on the assumption that three major forces (pressure gradient, Reynolds stress gradient, and nonlinear canopy drag) within canopy are in balance for gentle hills under neutral conditions. The momentum governing equation is closed by the velocity-squared law. This new model has many ad...

This study explores the relationship between laser waveforms and canopy structure parameters and the effects of the spatial arrangement of canopy structure on this relationship through a geometric optical model. Studying laser waveforms for such plant canopies is needed for the advanced retrieval of three-dimensional (3-D) canopy structure parameters from the vegetation canopy lidar (VCL) missi...

This paper presents empirical and theoretical analyses of spectral hemispherical reflectances and transmittances of individual leaves and the entire canopy sampled at two sites representative of equatorial rainforests and temperate coniferous forests. The empirical analysis indicates that some simple algebraic combinations of leaf and canopy spectral transmittances and reflectances eliminate th...