inopy cover metrics. 
LAI product will be 
011 and will continue 
of Project 2.07 is to 
>s and derive them at 
| Over representative 
rived from the in situ 
concerned with upper 
y cover. Three study 
e been identified for 
ifically chosen to be 
. The three areas are 
eek. The focus of this 
ind Watts Creek study 
:d. It is considered by 
f Sustainability and 
lands on which the 
atural and sustainable 
  
 Grank Reference Area Research sie 
  
0 60 
  
Kilometers 
Reference Areas 
rence Area (36°45°S, 
erophyll forest and is 
ure 1). The reference 
that includes several 
Bark (Eucalypytus 
ptus macrorhyncha), 
rey Box (Eucalyptus 
is dominated by the 
oodgate et al., 1994) 
  
‘Box Ironbark Forests or dry/lower fertility Woodlands’ and 
‘Dry Forests - Exposed and/or lower altitude’. 
The topography of Rushworth is mainly low-lying undulating 
land with a few minor gullies. The elevation ranges from 195m 
to 240m above sea level. Typical of the box-ironbark forests, 
no streams in the area carry permanent water but rather act as 
drainage lines. The climate is Mediterranean with hot, drought- 
prone summers and cool winters. 
Watts Creek: The Watts Creek Reference Area (37°41°S, 
145°41’E) is located on the slopes of Mount Donna Buang. The 
area largely comprises a mature open forest of Mountain Ash 
(Eucalyptus regnans). Regrowth and older mature stands of 
Mountain Ash, Shining Gum (Eucalyptus nitens) and Alpine 
Ash (Eucalyptus delegatensis) occur at higher elevations and 
there is a small area of scrub. The other structural form is 
closed forest Myrtle Beech (Nothofagus cunninghamii) in the 
main stream gullies. The dominant EVCs are ‘Wet or Damp 
Forests — Damp’ with smaller areas of ‘Rainforests’ and 
‘Riparian Forests or Woodlands’. There are very small areas 
where the EVC contains areas with no vegetation. Watts Creek 
is representative of the plateaux and slopes of the upper 
watershed areas south of the Great Dividing Range. It has been 
part of Melbourne’s water supply catchment since 1891. 
The elevation ranges from 900m to 1220m above sea level. The 
slopes have been steeply dissected by the young degrading 
Watts Creek tributaries. Slopes of the order of 15° to 20° can be 
found. The climate of the upper Watts River watershed is cool, 
wet and temperate. There exists a pattern throughout the area of 
increasing rainfall and decreasing temperatures with elevation. 
23 Terrestrial Remote Sensing Instruments 
A variety of active and passive terrestrial remote sensing 
instruments are intended to be utilised in this research. It must 
be noted that the metric being derived is in fact Plant Area 
Index (PAI) instead of LAI, as the gap fraction method fails to 
differentiate between foliage and non-foliage elements of 
vegetation (Coops et al., 2004). 
LAI-2200: The LAI-2200 Plant Canopy Analyser is a passive 
sensor used to compute LAI and a variety of other canopy 
Structure attributes from radiation measurements. The 
instrument is made with a fish-eye optical sensor. The 
ceptometer sensor has five circular rings sampling a 148° field 
of view (FOV). Measurements are made both above and below 
the canopy in order to determine a ratio of the radiative transfer 
of sunlight through the canopy. It is a proven method to 
(mine LAT and related gap fraction metrics (Chen et al., 
991). 
DHP: Digital Hemispherical Photography is a passive sensing 
technology that provides a large FOV image at the point of 
capture. The DHP setup used in this research comprises a 
Nikon D90 Digital SLR camera with a Sigma EX 180? 4.5mm 
circular fisheye lens. The resolution of the camera is 12.3MP. 
Gap fraction is calculated through classification of the image 
Into sky and non-sky elements (Chen et al., 1991). 
         
    
   
   
    
    
    
    
   
    
     
   
    
     
   
   
    
   
   
   
   
  
  
   
     
  
   
  
      
   
  
   
   
   
  
    
    
    
    
    
CI-110: The CI-110 is passive self-levelling imaging sensor. It 
has a 180° FOV and a 24 sensor Photosynthetically Active 
Radiation (PAR) wand used to measure the amount of incident 
solar radiation in the visible spectrum. The imaging device is 
restricted to a resolution of 0.4MP, which is much lower than 
the Nikon D90 SLR. The gap fraction is calculated with the 
same method as the DHP, where the image is classified into 
sky and non-sky elements. 
TLS: Terrestrial laser scanners produce a very dense 3D point 
cloud, which provides a rich representation of the forest 
environment from the ground up (Vosselman & Maas, 2010). 
The TLS to be used in this research is the Leica Scan Station II. 
The Scan Station II is a survey grade accuracy TLS and has a 
range of 300m at 90% reflectivity. It has a 360° horizontal and 
270° vertical FOV. It attributes each point with a red, green, 
and blue (RGB) colour value. The laser is Class 3R, operating 
in the Green band (106-302nm). TLS has can be used to derive 
gap fraction from the ratio of received returns to total emitted 
points (Danson et al., 2007). 
Modified densiometer: Traditionally, FPC is derived using a 
densiometer attached to the end of a pole which has been 
adjusted to the operator’s height. A laser rangefinder is 
attached to the end of the pole with the densiometer. The 
rangefinder records the height to the first vegetation or canopy 
intercept. This provides a characterisation of the bottom of the 
canopy. The laser rangefinder attached to the pole is the 
Trimble Trupulse. The height and FPC metrics will be used to 
validate the FCOVER metrics from the DHP and CI-110. The 
rangefinder measurements will be used to compare against the 
TLS point cloud. 
2.4 Terrestrial Instrument Comparison 
The first aim of this research was to conduct a comparison of 
active and passive terrestrial remote sensing technologies 
available to produce LAI and canopy cover metrics. The 
instruments to be used for comparison are; DHP, LAI-2200 and 
CI-110 for the passive sensors, and the TLS for the active 
sensor. However, results from only the DHP and LAI-2200 
over a subset of the sampling design will be presented here. 
The comparison was conducted at Rushworth to provide an 
indication of the degree of interoperability and transferability 
of technologies and methods. A gridded sampling design was 
developed to compare the instruments over a number of points 
at one sample location in Rushworth (see Figure 2). 
The 40x40m grid consists of three areas of varying sample 
density. At the centre of the plot there is an 8x8m grid sampling 
at the highest density of every 1m. Surrounding the 1m grid is a 
24x24m grid sampling every 2m. The 2m grid extends out to 
the 40x40 grid sampling at the lowest density of every 4m. 
There are 81 points at the 1m density, 144 points at the 2m 
density, and 72 points at the 4m density, totalling 297 points for 
the 40x40m grid. 
A field survey during March 2012 was conducted in Rushworth 
testing the feasibility of the 40x40m sampling design. DHP, CI- 
110 and modified densiometer were captured at every point in 
the grid. LAI-2200 was captured at only the 4m sampling