ds 
Hildebrandt (F.R.G.) agreed with Dr. Olson that 
generalizations had been made before methods 
and techniques had been fully verified or cor- 
roborated. Dr. Hildebrandt asked Dr. R. Welch 
(U.S.A.) why orthophotos were needed on flat 
delta areas. Dr. Welch pointed out that only 
rectification for tilt was done — not the full ortho- 
photo process. 
Dr. Hildebrandt asked Mr. Kolouch if he agrees 
with him in that the type of pollution influences 
in the spectral signatures and that it is not pos- 
sible to choose certain spectral bands. Mr. -Ko- 
louch replied that the results apply only to the 
Jade. Dr. Thomson commented further that the 
particles should be measured before generaliza- 
tions were made. Mr. R. C. Heller (U.S.A.) added 
that values giving the degree of successful 
detectability should also be accompanied by 
confidence statements such as the standard 
deviation of detectability. 
Dr. Thomson then asked Dr. Wieczorek how 
costly it was to use large computers for classifi- 
cation work. The latter agreed that the cost and 
efficiency of computer operations were important 
considerations in commercial applications but 
felt that research experiments, though done on 
expensive large computers, should be continued, 
especially when the computer was available for 
no charge. 
Mr. J. Speight (Australia) felt that there had been 
little discussion of dynamic models which might 
present a more complete picture of the circula- 
tion and productive charasteristics of marshes, 
and the relationships between vegetation patterns 
and water depths, flow patterns, velocity, fre- 
quency of inundation, etc. Dr. Olson agreed with 
this statement. 
Mr. J. Skorve (Norway) enquired about the effect 
you can get on any kind of image use with sedi- 
ments springing from sweet water into salt en- 
vironment. Dr. Wieczorek replied that little work 
can be done in this area and that remote sensing 
was capable of only general differentiation — 
the finer ones had to be left to chemical analysis, 
spectral analysis and other laboratory techniques. 
Dr. Olson added that better luck may be had with 
floating materials. 
Dr. A. Fontanel (France) asked if the quantifica- 
tion of chlorophyll content was possible.in the 
spectral bands mentioned. Dr. Olson did not 
think so because small quantities close to the 
surface have the same appearance as greater 
quantities at some depth. Dr. Fontanel asked 
further what resolution was achieved in the 
computer studies carried out by Dr. Wieczorek 
who replied 5—10 lines per millimeter and con- 
tinued with a detailed explanation of the method 
of analysis used. 
When adjourning the session the chairman 
established that there is a great deal of material 
concerning remote sensing also in the Papers 
of other Commissions, especially in those of 
Commission |. 
Friday, July 16, 1976, from 9.00 to 10.30 and 
from 10.45 to 12.15 
Session 3 of Commission VII 
Topic: Natural Resource Surveys 
Chairman: Dr. L. Sayn-Wittgenstein (Canada) 
E ae SPO 
PER LEE nt on Bh i ro mm rc art Bert ot Po doser ARAL m 
ILLE ll 
Invited Paper 
Author: Mr. R. Heller (U.S.A.) 
Title: Natural Resource Surveys /P VII/06 
Panel Discussion 
Topic: Applications in Resource Inventories 
Moderator: Mr. R. Heller (U.S.A.) 
Panelists: Dr. P. M. Fagundes (Brazil) 
Dr. S. Baker (U.S.A.) 
Dr. C. Girard (France) 
Dr. L. K. Kauranne (Finland) 
Mr. J. Speight (Australia) 
Mr. E. Amadesi (Italy) 
Mr. Fagundes presented part of Working Group 
Report VII/4: "Resource Inventories in the 
. Tropics" WGR VII/02. 
Dr. Baker gave a brief review of his paper: "A 
System of Remote Sensing and Mapping for 
Developing Countries” PP VII/04. 
The title of Dr. Girard's paper was "Utilisation 
de la télédétection dans la connaissance des 
dommages causés aux cultures" PP VII/16. 
The next to speak on applications in resource 
inventories was Dr. Kauranne. He reported that 
the results of engineering geological interpreta- 
tion of black and white (1:6000), color and false 
color (1:8500) stereo airphotos from a 3 km? area 
in glaciated terrain in South Finland had been 
compared with the results of field observations 
and with each other. 
The constant error in repeated measurements of 
area of formation had been x 596 and difference 
(error) in repeated interpretation about 8% ex- 
cept for silt, which had been greater. The reli- 
ability of the geological interpretation for black 
and white airphotos controlled by field observa- 
tions had been from 67 to 86 per cent; that for 
colored airphotos from 69 to 89 per cent; and 
that for false color airphotos from 70 to 88 per 
cent, depending on drift formation PP VII/19. 
Mr. Speight then summarized his paper: "De- 
scription of Landform Patterns on Air Photos" 
PP VII/36. 
Mr. Amadesi spoke on the "Use of False Color 
Photos for the Concrete Utilization Territory Map" 
PP VII/O3. 
The following observations were made during 
the general discussion: 
Mr. Heller was not certain how cameras were 
used in conjunction with orthophoto maps. 
Dr. Baker explained that supplementary photos 
from such cameras could be used to update or 
change the maps directly by registering on com- 
mon image data. 
Dr. S. Ihemadu (Nigeria) asked Mr. Heller if filters 
could. be selected for the high definition color 
infrared films referred to (SO-131) which would 
be appropriate for prevailing photographic con- 
ditions. He replied that none is required since 
the film has a special, built-in filtering (minus 
blue). 
Mr. A. Jones (Australia) remarked that in the same 
way that developing countries learned analytical 
aerial triangulation through trial and error, so 
should they experiment with new remote sensing 
techniques, especially with photographic image 
enhancement techniques. In response, Dr. C. 
Olson pointed out that digital methods would 
prove superior in the long run because the 
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