SIMPLE PIIOTOGRAMMETRIC METIIODS FOR MAPPING OF VEGETATION
POLYGONS BOUNDARIES IN NATIONAL PARKS IN AFRICA
Professor hab. dr Aleksandra Bujakiewicz
Head of Department of Surveying
School of Engineering, University of Zambia
P.O.Box 32379 Lusaka, Zambia
Commission IV, Working Group I
KEY WORDS: Mapping, GIS, GPS and Aerial Triangulation, Optical Rectification, Vegetation Polygons.
ABSTRACT
Wildlife management in national parks requires various types of data to be analized. Evaluation of vegetation is one of the
most important tasks needed for wildlife control and conservation. National parks in Africa cover large areas and
therefore photogrammetric and remote sensing techniques are the most suitable. Since the boundaries of vegetation
polygons are not shown on the medium scale topographic maps, therefore there is need for fast and cheap
photogrammetric methods to be used for their determination. In a project carried out by the joint Zambia - United
Kingdom team, the whole of Kasanka National Park and surrounding Kafinda Game Management Area in Zambia was
mapped and then classified into physiognomic habitat types, in respect to vegetation polygons and other features. Low cost
GPS technology in conjunction with graphical-analytical aerial triangulation have been used for determination of
planimetric control needed for mapping of vegetation polygons boundaries and geometrical positions of other features with
the use of an optical rectification device - sketchmaster. Thematic information, concerning types of vegetation and other
features, was collected by aerial photography interpretation supported with field verification. A digital data base was
created and processed with ARC/INFO software.
1. INTRODUCTION
Preservation of natural beauty in large national parks in
Africa requires careful management, control and
conservation of wildlife resources. Their proper inventory
needs many types of data, which have to be collected,
processed, analysed, up-dated and presented. Digital data
bases are the most convinient and easiest form to process
with the use of various digital mapping, remote sensing
and GIS softwares. Mapping and evaluation of vegetation
in areas occupied by national parks are very important in
wildlife management. National Parks in Africa cover
usually large areas, very often partially not available for a
direct survey, and therefore aerial photographs and other
remote sensing data are the best source for vegetation
mapping. Boundaries of vegetation polygons are not shown
on medium scale topographic maps, as for example
1:50000, which is the basic map for rural areas in most of
Southern African countries, including Zambia.
Conventional photogrammetric methods of aerial
triangulation for planimetric control densification and
stereocompilation with stereoplotters/analytical plotters for
mapping are too expensive, complicated and time
consuming to be attractive for supplementing of 1:50000
map of national parks with vegetation polygons and other
features. Production of photographic maps from aerial
photography or remote sensing imagery is faster and
cheaper and because of their pictorial form, large amount
of valuable information is available. However, orthophoto
technology and even ordinary rectification with
mechanical-optical rectifiers have not been implemented in
many of African countries, including Zambia. Therefore,
there was need to use some other fast and low cost
photogrammetric approaches for control determination and
mapping of vegetation boundaries in national park.
Simple photogrammetric approaches for field control
densification and mapping were proposed and applied by
the author in the project concerning mapping of habitat in
the Kasanka National Park and surrounding Kafinda
Game Management Area in Zambia, for the use in wildlife
conservation management and scientific research in this
Park. The whole project, which was carried out by the
joint Zambian - United Kingdom team, included the
following two parts;
(1) Photogrammetric mapping of boundaries of vegetation
polygons and other features in the National Park, carried
out in the Department of Surveying, University of Zambia
[Bujakiewicz, 1993].
(2) Collection of data concerning types of vegetation in the
Park, based on aerial photography interpretation and field
verification, creation, processing and analysis of digital
date base with ARC/INFO software, carried out by the
Department of Biological Sciences, Manchester
Metropolitan University [Cassels, 1994].
This paper concentrates mainly on the first part of the
project, concerning photogrammetric compilation.
However, the final results of some GIS processed data will
also be presented.
2. PRINCIPLES OF SIMPLE PIIOTOGRAMMETRIC
METTIODS FOR CONTROL DENSIFICATION
AND MAPPING
Control densification. Densification of planimetric control
proposed by the author for the purpose of this project has
154
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996
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