yellowing and finally harvesting. 
Figure 2 gives an outline of the proposed system. 
An initial data base of potential rice producing 
units has to be assembled. The irrigation unit, with 
its uniform irrigation and vegetation timescale, 
could be used as a base unit. This database will be 
filled by data from satellite imagery, aerial 
photography and fieldwork. The accuracy of this 
database is therefore not exclusively depending on 
the geometrical accuracy and resolution of satellite 
imagery. The operational 
system will then use the satellite data to identify 
whether the fields are actually irrigated and wether 
rice is growing and being harvested. 
4.3 Assessment of yield and detection of pests and 
diseases 
Apart from the identification of rice fields, remote 
sensing can also be used to detect the ratio between 
the high yielding varieties and the convential varie 
ties. Possibly a further detailed subdivision in 
these varieties could be made, but this has to be 
studied. 
In areas where crop diseases or pests are 
occurring, crop development monitoring can be used to 
determine the spread of the disease. To make disease 
and pest monitoring possible, the effect of the 
disease should be such that crop colour and 
associated structure have changed to such a degree, 
that the image interpreter can conclude that the 
cause of the change in crop appearance and associated 
patterns, should be attributed to the outbreak of a 
disease or pest. This information could be used to 
improve the efficiency of field surveys and of the 
measures to bring the diseases and pests under 
control. 
It is expected that the high repetition of obser 
vation in combination with the high spatial 
resolution and the spectral band selection optimized 
for vegetation monitoring, can provide an excellent 
tool for crop disease and pest control. 
The information on the extent of pests and 
diseases, in combination with the information on the 
distribution of the different rice varieties, can 
improve the yield forecasts and estimates. The 
related benefits are the reduction of production 
losses and the improved efficiency of pest control by 
a reduced usage of pesticides. On the basis of remote 
sensing data an early warning system could be 
established in order to minimize economic losses due 
to pests and diseases. 
5 UTILISATION PREPARATION PLAN 
Remote sensing as a source of information is already 
used by a number of organizations in Indonesia (e.g. 
Public Works, Transmigration, Forestry, Environment, 
Central Bureau of Statistics, Bakosurtanal). The 
projects of these organisations will benefit from the 
direct reception of Landsat images by the LAPAN 
groundstation, which will be operational in the near 
future. In the past these images arrived with long 
delays (and often too late) from foreign stations. By 
upgrading the station in the future, it will be 
possible to receive also the high resolution images 
from Landsat 5 and Spot and lateron possibly TERS. 
A requirement exists for an overall approach to the 
application of remote sensing techniques in 
Indonesia. Part of this should be an inventory of the 
present practical applications of remote sensing in 
Indonesia. In a large number of projects remote 
sensing methods are already used as an important 
source of information, especially in those cases 
where other sources of data, like topographic maps 
are outdated. In a stepwise development of remote 
sensing all the different available sources of data 
should be used in an integrative approach. 
Important steps are designated by the present 
Landsat station, for the reception of MSS data, 
becoming fully operational and the updating of this 
station to X-band for the acquisition of high 
resolution data like Landsat Thematic Mapper (TM) and 
Spot. On the one hand this station will supply data 
for applications (and research) and on the other hand 
it will produce on the job training in the handling 
of large datastreams as will be provided by most 
future satellites. 
Although no requirement exists for a centralized 
remote sensing institute, a coordinated national 
effort is required to develop the remote sensing 
techniques into operational tools for the Indonesian 
development programs. The platform for such a 
national program for the development of remote 
sensing is already available in the different 
organisations involved in the research and 
development as well as in the practical use of remote 
sensing. 
6 CONCLUSIONS 
Preliminary analysis of potential benefits of a 
satellite remote sensing system with the capability 
to monitor crops and forests indicates that multi 
million dollar benefits may be expected. Such a 
system is not yet in existence, but from imagery of 
present satellites the feasibility of realising these 
benefits can be demonstrated. Further studies are 
pursued in order to substantiate these findings and 
to arrive at conclusions, if and when such a multi 
million dollar investment for a dedicated equatorial 
earth observation system for the monitoring of 
renewable resources is justified. 
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Mears, L.A. 1981. The New Rice Economy of Indonesia. 
Yogyakarta, Gadjah Mada University Press. 
Central Bureau of Statistics. 1982. Statistical 
Yearbook of Indonesia. Jakarta. 
Central Bureau of Statistics. 1981. Products Tanaman 
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Malingreau, J.P. 1980. A Detailed Indonesian Case 
Study. Berkeley. 
Malingreau, J.P. 1983. Remote Sensing in Indonesia, a 
Review of the Available Technology and its 
Applications of Resources Surveys. Berkeley. 
Machin Ervan 1981. Use of Remote Sensing for Crop 
Production Estimation in Indonesia. Jakarta. 
Machin Ervan et al 1980. Remote Sensing for 
Indonesia, Agricultural Assessment: Evaluation 
Report for Pilot Survey in Lampung, Sumatra. 
Jakarta 
Cyril Ponnamperuma 1984. A case for the remote 
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