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Title
Remote sensing for resources development and environmental management
Author
Damen, M. C. J.

KEY
R - Residential areas
I - Industrial
S- Service
W Water bodies
— Canals
Fig 1. Map of the land-use in the Blackbrook
Valley
4 DATA EXTRACTION - THE CLASSIFICATION
The photographic interpretation was based on
a habitat classification devised for this
project. Habitat mapping is well suited to
remote sensing as an habitat unit has a
larger surface area than individual species
communities and therefore is more easily
identified. The classification is divided
into four groups:
1 land with no cover,
2 land with man-made cover,
3 land with water cover and
4 land with vegetation cover.
In this paper only land with vegetation cover
will be discussed. The vegetation categories
are based on the structure and density of the
dominant growth forms. The distinction
between open and closed woodland and
shrubland categories were dictated by the
distance between foliage canopies (see
Fosberg and Peterken 1967).
28 Tree cover +3m height
29 Broadleaf communities
30 Single tree
31 Closed woodland
32 Open woodland
33 Linear woodland
34 Woody shrub
35 Coniferous communities
36 Single tree
37 Closed woodland
38 Open woodand
39 Linear woodland
40 Woody shrub
41 Shrub cover -3m
42 Broadleaf communities
43 Closed shrub
44 Open shrub
45 Linear shrub
46 Coniferous, spikey communities
47 Closed shrub
48 Open shrub
49 Linear shrub
50 Herbaceous cover
51 Ruderal communities
52 Tall herb and fern communities
53 Rough tall grassland communities
54 Wetland herbaceous communities
55 Tall fragmentary marginal communities
56 Smooth turf grassland (unmanaged)
57 Smooth turf grassland (managed)
58 Rough turf grassland
59 Floating vegetation
60 Submerged vegetation.
Figure 2. Classification categories
Although the idea of an universal legend is
attractive no standard classification exists
for ecological or urban surveys therefore
new legends need to be devised for individual
projects to ensure the detail necessary is
obtained. The vegetation communities
identified by the N.C.C. were the basis of
this habitat classification, allowances being
made for the difference in the survey's
resolution.
The accuracy of the photographic
interpretation and mapping was checked for
1981 and 1984. A pilot test had identified
the categories which were frequently
misc1assified for example bracken.
Previously this had been an individual legend
category, but due to interpretation
difficulties it was included in the tall herb
and fern category. The accuracy level
achieved for the 1984 analysis was better
than the 1981 figure. This was a result of
the time period between the dates of the 1981
photographs and the field work, 1983. A good
deal of development had taken place in the
area in this period. The 1981 interpretation
was 89.5% accurate and the 1984
interpretation was 97.6% correct. The
statistical tests (see Ginevan 1979 and
Arnold 1985) suggest the number of errors
did not occur by chance.
5 DATA ANALYSIS
In the literature, studies using air
photographs to predict bird population
numbers have not been very successful.
Various researchers have concentrated on
predicting bird species numbers, bird
abundance and bird species diversity using
variables measured in the field such as area
of woodland, foliage height diversity,
foliage canopy density and woodland
isolation. It was decided to investigate if
information about the variables used in these
techniqi
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