International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004
drainage areas and the average of the discharge of an order of
zero (
800
Fig. 10. Drainage map of the Madeira river basin
Number
10000
1000 B.
100
10 “+
Zem Fist Second Third Fourth Fifth’ Onder
Fig. 11. Number of branches vs. Orders
Length fm)
10000
100 +
Fist Second Thid O xier
In
22 0 mer
Fourth
Zero First Second Thád
Fig. 13. River slope vs. Orders
Table 1. River characteristics for each order
Order 0 (estimate) 1 2 3 4 5
Number of the branches 1191 227 42 8 3 1
Length of the branches (km) 48.4 82.5 139.6 | 428.3 | 507.6 | 312.4
River slope 1.573 1570 | 1.567 | 1.562 | 1.553 | 1.556
Table 2. Estimated characteristics of the order zero
and the average of discharge
Length of the branches Drainage area | Average of the discharge
(km) (km?) (m/s)
Estimate of the order of zero 48.4 632.6 13.5
isible river characteristics
Kvisible fivcr enaracte 31.5 628.0 13.4
estimated from SAR
Length (km)
100000 p——á—
10000
10000000
Ana (m2)
Dschame (m
100E*13 [e E
1D0E+12
100E+11
100E410
10000 100000 10000000
Ara km2)
1000000
Fig. 15. Discharges vs. Areas
4. CONCLUSIONS
We analyzed the JERS-1/SAR images about 12 scenes from
1993 to 1997 in the Amazon, and found out the characteristics
of the river shapes with the river geomorphology correlated the
discharge well. Namely, as a result of the Fourier and wavelet
analyses, the more discharge had the less spatial frequencies,
while the less discharge had the higher spatial frequencies. In
particular, we found that the continuous wavelet analysis was
the best method to estimate the river discharge. Moreover, by
the river geomorphology or Hack’s and Horton's rules with the
macro scaled drainage map, we could estimate the river
characteristics of the order of zero, and they almost
corresponded with the invisible river characteristics estimated
from SAR images. However, for the reason the characteristics
were averaged for each order, the precision had some of error.
Therefore, we could obtain the difference between some rivers,
but a very small change such as a seasonal change was hard to
be derived. In the future, we will analyse and estimate the
seasonal change of its discharge with the precipitation data and
brightness of the river. Accordingly, by the analysis of the river
characteristics, we could estimate the discharge of the narrow
branches in the Amazon basin, and monitor the water budget
and soil runoff.
References
Takako Sakurai-Amano, Joji lisaka, and Mikio Takagi, 2000.
Detection of narrow open-water channels from JERS-1 SAR
images of Amazon forests, Proc. of SPIE's Second International
Asia-Pacific Symposium on Remote Sensing of the Atmosphere,
Environment, and Space, Sendai, Japan, pp.120-130.
Takako Sakurai-Amano, ef al, 2001. A year change and
monthly division precipitation of a river in the Amazon forest,
Soc. of Photogrammetry and Remote Sensing, Toyama, Japan.
Shigemi Takagi, 1974. River Morphology, Kyoritsu publication.
892
fo
Fi
the
CO!
an
Ce
Or
roc
cre
Cal
int
rin
to
CO!
Sul
alr
the
Re
CO!
po