DETECTION AND REGISTRATION BY SPACE PHOTOGRAPHS OF CHANGES
IN THE FOREST FUND AREAS CAUSED BY SEVERE FIRES AND CLEAR CUTTINGS
R.I. Elman, M.D. Breido
UNIITslesresurs, Moscow, USSR
ABSTRACT
Programme technology of the automated detection, registration and assessment by space photographs of
changes in the forest fund areas caused by severe fires and clear cuttings is considered. The technology is
based on the combining in the automated regime the space photograph with the cartographic and forest
mensuration data bases. It allows to timely determine the characteristics of each homogeneous plot of the
image and to use them for the two-stage photointerpretation. On the first stage the survey fragment of the
photograph is interactively analysed in order to quickly extract the areas, gone by fires, and clear cuts. Then
the extracted plots of the photograph are accurately connected to the cartographic topo-base and are viewed
under the "magnifying glass" in order to get data about the location and the size of cuts and burnt areas. By
way of automatic comparison of contours of burns and cuts of the past assessment periods which are stored
in the cartographic base, with contours of these areas extracted by the space photograph, places of newly
appeared cuts and burns are determined. On the final stage the actualization of the cartographic and forest
mensuration data bases is done, and the observation of regulations is evaluated.
Key Words: data base, space photograph, interpretation, extraction, registration, assessment, actualization
INTRODUCTION
Method of detection and registration of changes in the forest fund areas caused by severe fires and clear
cuttings includes the preparatory stage, preliminary visual photointerpretation, input of the photograph into
the system of interactive image processing, geometrical correction, interpretation, extraction of cutting contours
and areas gone by forest fires, their rectification by control points into cartographic projection, area calculation
and correction, forming of operative maps and output of final documents. The general functional diagram of
the method is presented in Fig.l.
The source data are materials of space photo and scanner photography obtained with the instruments of
medium and high resolution, and also the digital cartographic base, combined on the programme and physical
level with the forest mensuration base and used for topobase control, interpretation of photographs and
presentation of results in the graphical form.
Remote sensing data may be presented in the form of prints, dubbing negatives and records on magnetic tape
in spectral bands of 0.6 - 0.7 micrometers, 0.8 -1.0 micrometers of medium resolution (175m on the ground),
and in the bands of 0.6 - 0.7 micrometers, 0.8 - 0.9 micrometers of high resolution (45m on the ground). For
the extraction of clear cuts also space photographs at scale 1:280000 with the ground resolution of not lower
than 10 metres can be used.
The basis for the digital cartographic base is forest management tablets and maps at scale 1:1000000 and
1:8000000.
Preliminary work includes the creation of the digital topographic base, the base of control points, and collection
of information about the planned areas of cuttings and centers of fires recorded by the aerial forest fire
protection service.
On the stage of preliminary interpretation by multitemporal photographs of medium resolution in the band of
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