ial 
he 
ch 
he 
Op 
» 
an 
ny 
ne 
as 
op 
of Agriculture” and computed agricultural 
production. From this figure, north part of 
United States(N.A.) where Corn Field is 
dominant has estimated lower agricultural 
production than statistics, and south part of 
US(S.A.) where 
horticulture including 
  
  
[10*kcal/HA] 
900 Corn (N. A s : 
= 2000 : : 
1500 
  
  
   
1000 
  
Vegetables (S.A! 
  
500 
  
  
L 1 
0 1000 2000 3000 
Productivity (computed) 
y p ad cou 
  
© 
Productivity Statistics) 
no 
Fig-6 Comparison of Agricultural Productivity 
between Statistic data and 
estimated value for 3 regions. 
  
  
vegetables and fruit cultivation is dominant has 
estimated higher than statistics. These are 
considered to be caused by following reasons: 
a) There was no considerations on crop type 
distribution in land use map during the 
conversion from crop production(weight) to 
calorie base. Crop production(weight) per 
unit area is different depends on crop type, 
for example, 2.2 MT/HA for wheat and 7.3 
MT/HA for corn(from FAO Web site at 
above). However it is difficult to monitor 
the distribution for each crops from 8km 
resolution satellite data. 
b) Cultivation is not made only one time 
in a year in many places in the world. The 
statistics count cultivated area considering 
how many times cultivation was made, 
however the area was counted only one 
time in our processing. 
However when we discuss the productivity in 
specified region such as “north part of USA” or 
“Indochina Peninsula" etc, the estimated 
agricultural productivity is effective to 
understand the distribution of it. 
It is required that higher resolution analysis 
should be examined using 1km NCAA data or 
LANDSAT data with detailed statistics in order 
to validate the algorithm. 
REFERENCES 
Goward,S.N. and Huemmrich, KF, 1992, 
Vegetation Canopy PAR Absorptance and the 
Normalized Difference Vegetation Index: An 
Assessment Using the SAIL Model, Remote 
Sensing of Environment 39, pp.119-140. 
Prince,S.D., and Goward,S.N., 1995, Global 
primary production: a remote sensing approach, 
Journal of Biogeography 22, pp.815-835 
RuimyA., Saugier, B., and Dedieu, G., 1994, 
Methodology for the estimation of terrestrial net 
primary production from remotely sensed data, 
Journal of Geographical Research, 99,pp5226 
Intemational Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998 
469