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CHaPTeR 3
Method of data collection
and analysis
3.1 Data audit and evaluation
3.1.1 Background
Historically, vegetation has been classified and mapped using various techniques. Sun et al.
(1997) found that four main classification systems have been used in Australia; they include:
➜ plant physiognomy: the general external appearance such as tree, shrub and fern
➜ plant structure: the vertical height and horizontal cover
➜ species composition
➜ environmental variations
However, regardless of which vegetation classification system is used most are informed by
floristic records which have resulted from vegetation surveys. Vegetation surveys provide a
snapshot of the environment: the plant species that occur at a particular place and a particular
time. Such information provides quantitative data that can be numerically analysed by
sophisticated software programs to detect vegetation patterns that may not be easily
recognised by the human eye. Expert opinion often guides the analyses but the end product
relies on the quality of the data: the accuracy and completeness of species records, as well
as the even distribution and density of surveys across an area. Hence, in order to generate a
vegetation classification system and map, a comprehensive data audit is required; when all
existing datasets that meet minimum standards are collated, areas that require further survey
work can be identified.
This section outlines the methodology used to collate and evaluate existing vegetation surveys
conducted in the Hunter Central Lower North Coast (HCLNC) region. The data audit will
directly contribute towards the development of a regional vegetation classification and map.
The full results of the survey data audit are presented in volume 3 of this report (HCCREMS
2008b).
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