International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004
Int
R,zR.-a.)*e, Ru A, (12)
R, - &,0T,. (13)
1/7
e
o^ zl.24| —-
&, =1.24 T (14)
R, = sat! (15)
where E Evapotranspiration
e | A-(de /dT),
As d db eee ken da SEE Y*cpp/£l,
nens m es Qu = Available energy flux density (mm/day)
coniferous tree f(u) = Wind function (mm/day)
EN evergreen broad- leaved tree u = Mean wind-speed (m/s)
ENN deciduous broad- leaved tree e, = Saturated vapor pressure (hPa)
: : e, ^ Vapor pressure e (hPa)
Figure 7. Vegetation types R, = Net radiation (W/m? )
L, = Latent heat (72.454x 10 J/kg)
3.7 Comprehending Water Cycle R, = Short-wave radiation (W/m°)
es , > as = Albedo
Water cycle in forest could simply be showed as follows. Ru = Downward long-wave radiation (W/m? )
R^ = Upward long-wave radiation (W/m° )
PrE4D+G (9) = Emissivity of surface (=0.97)
T — Atmospheric emissivity
where RE Precipitation ; 5= Stefan-Bolzmann constant (5.67x10% Wm?K*)
ES Evapotraspiration T, - Atmospheric temperature (K) F
D River dischatge T, ^ Surface temperature (K)
G = Groundwater infiltration ;
: : N The albedo and the surface temperature were calculated from
These were Calculated from ihe rele semine daa, the CIS the Landsat/TM images. The PE is the mean of the
data, and the metrological data respectively 8 : : reflectance in the visible spectrum. Figure 9 shows the
We ; adopted t he monthly meteorol ogical grid data for calculated spatial distribution of the albedo. The surface
Breeipitation. Figure 8 shows the precipitation of the monthly temperature was calculated from TM6. Figure 10 shows the
meteorological grid data. estimated spatial distribution of the surface temperature. We
adopted the monthly meteorological grid data for atmospheric
temperature. Figure 11 shows the atmospheric temperature of
the monthly meteorological grid data. Wind-speed, vapor
pressure, and, short-wave radiation was used from the
metrological data. In addition, short-wave radiation was used
from the solar radiation. Table 4 shows metrological data used.
| : Ne
ans
reg
act
dis
: dis
Figure 8. Spatial distribution of precipitation
Evapotranspiration was calculated by the improved Penman’s
method.
A .
E = Qt foe, 6.) (10)
A*y 5 *4 Figure 9. Spatial distribution of the albedo
d= R, (11)
L,
January| Febrary| March | April] May | June Jul | August] Septem ber] O ctober Novem ber| Decem ber
w nd-speed 10 14 10 T1. 10 99 08 09 08 08 09 10
sohr radatbn | 423 598 723 | 648 | 784 6 44 822 6 90 452 396 306 384 Gr
vapor pæssuæ| 635 308 891 [891] 1209 | 1630 | 3405 | 4123 2104 14 92 1041 636 ev:
14
Table 4. Mean values of wind-speed, solar radiation, and vapor pressure inf
dis
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