LARS BRABYN
GEOGRAPHER
BSc(Hons), BA(Hons), PhD Cant
Lecturer
Research Interests
Geographical Information
Systems (GIS), landscape classification, biodiversity,and health
Landscape Classification using GIS
A
landscape classification process has been developed as part of Lars Brabyn's
Ph.D. at the Department of Geography, University of Canterbury. It is based on
GIS technology and uses standard digital topographical databases. Most hard
copy topographical maps in Western Countries are now available as GIS coverages
and can be analysed automatically using GIS. Information on the landforms,
vegetation, degree of human modification, and the influence of water can be
obtained and integrated into a landscape classification process.
Landform Classification using GIS
The automatic classification of macro morphological
landforms using GIS and digital elevation models (DEM) was investigated. A
process developed by Dikau et al, which automates Hammond's manual procedures,
was applied to a cross section of the South Island of New Zealand. Although it
produced a classification that has good resemblance to the landforms in the
area, it had some problems. For example, it produced a progressive zonation
when landform changes from plains to mountains, it does not distinguish open
valleys from a plains-mountain interface, and it was affected by micro relief.
Also, Hammond’s slope threshold was used even though slope was measured
differently. Although automating existing quantitative manual processes is an
important step in the evolution of automation, definitions may need to be
calibrated since the attributes are often measured differently. A new process
is presented that partly solves these problems.
PhD Thesis-Landscape Classification using GIS
and National Digital Databases
This study considers whether visual landscape character can
be classified using GIS. Landscape classification is needed to give landscape
researchers and planners a frame of reference for communicating and comparing
their research. Such classification is difficult because of the complex nature
of landscapes and because it must be explicit. Classification needs to be based
on theory, but there is a distinct lack of landscape theory. It is argued that
to effectively develop landscape theory a classification is required and that a
classification evolves with theory. GIS provides a suitable platform to
facilitate this evolution.
A set of criteria is established to which a landscape
classification should adhere. To be useful for evaluative and cognitive
research, a landscape classification needs to distinguish the important
characteristics that affect landscape. These characteristics are identified
from what little landscape theory exists: a landscape classification needs to
incorporate landform, vegetation, naturalness, and water; the classes should be
based on the public’s perception; the classes should be general and involve
compositions; and the classes should incorporate movement and exploration.
Besides these criteria, more general criteria that have been used on other land
based classifications also apply, particularly the need for a classification to
be repeatable.
The Use of GIS for Biodiversity Mapping in New
Zealand
This
paper discusses potential applications and current limitations of GIS for
mapping and modelling biodiversity in New Zealand. Three functions of GIS that
are important for biodiversity modelling are demonstrated. These are terrain
analysis, data integration and data visualisation. Terrain analysis can be used
to identify micro, meso and macro terrain indices. Data integration can be used
to determine the environmental characteristics of known habitats of species.
Data visualisation uses maps, graphs and statistics to make the enormous amount
of data that can be derived on a species' habitat easy to understanding. This
research has attempted to use "Public Good" New Zealand species location
data sets but had problems with access and format. It is argued that the
ability of computer hardware and the functionality of GIS software is being
under utilised in New Zealand for biodiversity mapping because of poor sharing
and storing of data, and an overall lack of co-ordination and leadership in
environmental information management.
The
purpose of this web page and associated images is to demonstrate what can be
done with the New Zealand National Vegetation Survey (NVS) databank and GIS
visualisation tools. Each species listed below is linked to a graphic that
shows the environmental characteristics of where the species is known to be
present. A summary of environmental characteristics of where the species is
known to be absent is also shown. This initiative is discussed in the paper
"The Use of GIS for Biodiversity Mapping in New Zealand". The GIS
visualisation tool requires the input data to be in a relation data format.
Only a subset of the NVS databank is available in this standard relational
format.
http://www.waikato.ac.nz/wfass/subjects/geography/staff/lars/
Prepared by Bob Dalrymple, PO Box 122, Dapto, NSW Australia 2350
eMail: bob@relativelyyours.com