965; Wool-
t years,
ing biomass
such as u-
estimate
o predict
pasture
inted out
76-0.78 um
use the
tion, and
heric water
eaf area
n, and ra-
infrared
., the 101W
to integ-
.ated at
■hich is
> of NOAA,
ysis(Fig.2)
ipling fra-
this area
the corre-
with the
idel, green
'ouse et al.,
will be
¡en leaf
' near inf-
:nsity, the
’ore, it is
) estimate
;hat the ND
of view be-
mgth effec-
l , and if
.s high and
î reduced to
984).
Tarim River
1 on the 29th
me, 1985,
of NOAA Sa-
îllite Cen-
ш, China,
ЗН2+СН-1 , and
labi«? I. Comparision of the MuAA AVIIkk and l^VNUSAl' 'iGS. Sources:
KidwelK1981),NASA(1976) and General tlectric(undated).
Chnractoristic
landsat/mss*
noaa/avhrr
inclination of orbit
°-
i
99.092°
ileinht above surface
916.6km
833km.
Number of orbits/day
14
14.2
Times of coverage at equator
09.30
07.30 descending,. .
, r, ->n . • J thOAA-e
19.30 ascending 1
02.30 descending,... . . ..
11.30 ascending r 0AA -‘
orbital period
103.3 min
102 min
Latitudinal coverage
B0°N-82°S
90°N-90°S
Cycle duration
18 days
c.l day
: round coverage
185 km
c.3000 km
Field of view(FUV)
+ 5.78°
C£°
+ 56
Instantaneous field ofview
0.086 mrad
1.39-1.51 mrad
(1FuV)
Grouc* resolution(nadir)
79m
1.1 km
Groijd resolution
79.5 m along
track 2.4km along track
(maximum off-nadir)
80 m across track 6.9km across track
Samples per IFOV
1.411
1.362
Number of channels
0.5 - 0.6
0.58 - 0.68
0.6 - 0.7
0.725- 1.10
0.7 - 0.H
3.55-3.93
0.8 - 1.0**
10.5 - 11.5
(U.5-12.5*«*)
Data precision
6 or 7 bit
10 bit
♦LANDSAT-4 has a rather lower orbit(725 km) and a cycle duration
of 16 days but overall the Mss has very similar properties to those
.of previous LANDSATs. It also contains the 7 band, 30 m IFuV The
matic Mapper.
♦•This is a more accorate repres«?ntation of the spectral bandwidths
than the value of 0.8-1.1 >im which is normally quoted.
*** un I40AA-7 only.
Table2. ground-collected predominately green clipped
wet biomass.
Plots
Sample names*
Coveraqe
(%)
wet biomass
(kg/mu)* *
1
Phragmites Communis
25 - 30
405
2
Phragmites Communis +
Alhagi Pseudoalhagi
• 40
936
3
High Phragmites Communis
25 - 30
585
4
Poacynum Hanjlersonii +
Glycyrrhiza Uralensis +
Lycium Kuthenicum
90
1305
5
High Phragmites Communis
50 - 60
1305
6
Calamagrostio Hpigejps
70 - 80
765
7
Phragmites Communis
10
315
6
Phragmites Communis +
Kereiinia caspica +
Kalidium caspicum +
Alhagi Pseudoalhagi
40
169
9
Short Phragmites Communis
20 - 25
270
10
Phragmites Communis
30 - 35
400
11
High Phragmites Communis
40
1080
*in Latin.
**One Chinese mu = 0.0667 ha.
through the HP1000 image processing system
in this center, a map(Fig.3) of the ND dis
tribution has been portryed. It is clearly
illustrated that the high ND value is along
both sides of the Tarim River, while the lo
ver ND value is in the south area where the
desert is occupied.
To compare the ND value with green leaf
biomass, 11 sampling locations with 1 m 2
area plot were operated, for each plot wet
grass matter by hand clipping was weighed,
and meanwhile, the ND value was calculated.
Pi# 2 The relationship between ND with the
field spectral radiator and wet
biomass in the test area.
Fig.3 The Normolized Difference for the Ta
rim River Basin in Xinjiang from NOAA AVHRR
on 13th of June, 1983.
WET BIOMASS (.kg/mu)
Fig.4. The relationship between Nd from NOAA
data and wet biomass in the test area.
Than, a correlation analysis is shown in Fi~
g.4. The sketch explain that the relation
ship between ND and green leaf biomass is
very available, and the correlation coeffi
cient arises to that of r = 0.95, According
