Potential applications of near infra-red hemispherical imagery in forest environments

Hemispherical photography is commonly used in studies investigating the light environment beneath the forest canopy. This paper documents a methodology to adapt a standard digital camera to take hemispherical images in the near infra-red. These images can then be post processed to calculate sky-view factors, branch/bole-view factors and foliage-view factors. The further potential of the instrument is then demonstrated by combining the near infra-red images with standard visible images to produce a hemispherical NDVI image. Further discussion is also given to the potential applicability of the techniques above the forest canopy.

[1]  N. Silleos,et al.  The use of multi-temporal NDVI measurements from AVHRR data for crop yield estimation and prediction , 1993 .

[2]  J. Clevers.  Application of a weighted infrared-red vegetation index for estimating leaf Area Index by Correcting for Soil Moisture , 1989 .

[3]  A. Huete,et al.  A Modified Soil Adjusted Vegetation Index , 1994 .

[4]  Michael Nobis,et al.  Automatic thresholding for hemispherical canopy-photographs based on edge detection , 2005 .

[5]  Margaret C. Anderson.  The geometry of leaf distribution in some South-eastern Australian forests , 1981 .

[6]  Frédéric Baret,et al.  Review of methods for in situ leaf area index determination Part I. Theories, sensors and hemispherical photography , 2004 .

[7]  S. Hale,et al.  Comparison of film and digital hemispherical photography across a wide range of canopy densities , 2002 .

[8]  C. Justice,et al.  A Revised Land Surface Parameterization (SiB2) for Atmospheric GCMS. Part II: The Generation of Global Fields of Terrestrial Biophysical Parameters from Satellite Data , 1996 .

[9]  R. Hall,et al.  A comparison of digital and film fisheye photography for analysis of forest canopy structure and gap light transmission , 2001 .

[10]  Edward J. Milton.  Low-cost ground-based digital infra-red photography , 2002 .

[11]  Lee Chapman,et al.  Rapid determination of canyon geometry parameters for use in surface radiation budgets , 2001 .

[12]  D. Randall,et al.  A Revised Land Surface Parameterization (SiB2) for Atmospheric GCMS. Part I: Model Formulation , 1996 .

[13]  R L Pearson,et al.  Hand-held spectral radiometer to estimate gramineous biomass. , 1976, Applied optics.

[14]  Jean-Yves Pontailler,et al.  Estimation of leaf area index using ground-based remote sensed NDVI measurements: validation and comparison with two indirect techniques , 2003 .

[15]  Sylvain G. Leblanc,et al.  Methodology comparison for canopy structure parameters extraction from digital hemispherical photography in boreal forests , 2005 .

[16]  M. Kafatos,et al.  Frequency analysis of natural vegetation distribution using NDVI/AVHRR data from 1981 to 2000 for North America: Correlations with SOI , 2002 .

[17]  C. Justice,et al.  The generation of global fields of terrestrial biophysical parameters from the NDVI , 1994 .

[18]  P. Rich.  Characterizing plant canopies with hemispherical photographs. , 1990 .

[19]  Richard A. Fournier,et al.  Integrating clumping effects in forest canopy structure: an assessment through hemispherical photographs , 2003 .

[20]  Sven Wagner,et al.  Relative radiance measurements and zenith angle dependent segmentation in hemispherical photography , 2001 .

[21]  Megumi Ishida,et al.  Automatic thresholding for digital hemispherical photography , 2004 .