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CHaPTeR 4 Results
following summarises information contained in the vegetation survey profiles, such as survey
age, floristics, survey plot type and size as well as cover / abundance score systems used.
4.1.2.1 age of surveys
The vegetation surveys collated date from
1975 (Alex Floyd, rainforest surveys) to
2007. The age of the surveys could not be
ascertained for over half of the datasets
(51%). For the surveys where the survey age
is known, the majority (26%) were within six
to 10 year age. A small percentage of surveys
were within 0 to five and 11 to 20 year age.
Only 2% of surveys were between 20 to 30
year age (Figure 4.1).
4.1.2.2 Floristics data
The majority of surveys (69%) have full
floristic data (i.e. records all species within a
designated survey site). A small proportion
of surveys (3%) have recorded either a
comprehensive species list (i.e. records
species within and outside a designated
plot site) or canopy-only species. Details of
the floristic data recorded were unknown
for approximately one-third of the surveys
collated (28%) (Figure 4.2).
4.1.2.3 Survey plot type
Survey plot type refers to the bounding
outline of the survey area. There are four
main plot types: quadrats, circular, transect
lines and dimensionless plots. Square
and rectangular quadrats are the most
commonly used plots as they are easy to set
up and conform to New South Wales State
Government standard practice (Keith &
Bedward 1999). Circular plots are round in
shape and are used to obtain particular types
of measurement such as tree density. Transect
lines (also known as line intercept) are used
to survey narrow bands of vegetation such
as riparian zones or roadside environments.
Dimensionless plots (also known as traverse
or random walks) are conducted in dense
vegetation types as they allow greater access
(Hnatiuk et al. in. press).
Figure 4.1. Summary of age of surveys
Figure 4.2. Summary of floristic data
information recorded
Figure 4.3. Summary of survey plot type