OREST 
REMOTELY 
edlyincrease in 
former Soviet 
evious studies 
has been little 
in. This paper 
mps located in 
ferenced using 
A) was created 
ication scheme 
plying remote 
and display of 
% of its total 
because more 
d or semi-arid 
rea 72 % are 
1g 28 % are 
1a] forests for 
Sheikh, 1987). 
inistan by the 
rced over four 
into Pakistan. 
were settled in 
"ince (NWFP). 
nost extensive 
f refugees for 
o have had a 
  
considerable negative impact on the forest 
resources of the region. 
The rapid increase of population in 
Siran Valley, located in NWFP (Figure. 1), has 
put considerable pressure on natural resources. 
This has caused severe problems of 
environmental and ecological degradation. In 
1989 population was estimated to be 569,000, 
with 91 % living in rural areas. The rural 
population depends entirely or in large part on 
agriculture for their subsistence. An additional 
111,000 Afghan refugees residing in ten 
refugee camps, brought the total population to 
680,000. This is an average density of 747 
people per km”. 
Significant destruction of forests in 
Siran Valley has occurred during 1978 to 1989. 
The major causes of destruction were the 
encroachment of forest land for agricultural 
purposes, illegal cutting, and over grazing of 
forest land. This destruction of vegetative 
cover resulted in serious ecological 
deterioration (Sardar, 1986). The process of 
ecological deterioration in terms of accelerated 
soil erosion, mass movement, and flash floods 
can be observed throughout the watershed. 
The intensity increases during the monsoon 
period. Flash floods and massive landslides 
during the monsoon season cause significant 
damage to mountain roads, private property, 
forests, and the low-land agriculture (personal 
field observations, 1992). Severe soil erosion 
associated with removal of vegetative cover 
increases the suspended sediment load in water 
courses, which eventually augment the siltation 
of hydroelectric and irrigation reservoirs 
(Lodhi and Naqvi, 1984). 
2. STUDY AREA 
The Siran Valley is situated between 
34° 21' and 34° 48' north latitude and 72 55' 
and 73° and 19' east longitude. It covers an 
117 
area of 1,675 km?. It is bounded on the north 
by the mountain ranges of Tikri, Nandhar, 
Hillan and Alai, and on the east by the 
mountain range extending southward from the 
peak of Musa-ka-Massala (4200 m). On the 
south Siran Valley is bounded by the low, 
undulating hills of the Lower Tanawal, and the 
Pakhli Plain. The Black Mountains lie to the 
west. The Siran River rises near the peaks of 
Bhogarmang Valley and is fed by a large 
number of streams and springs emanating from 
glaciers. From its source to the town of Dadar, 
the Siran River traverses through Bhogarmang 
Valley and enters into the Pakhli Plain. It 
flows in a north-south direction, then slowly 
winds its way in a southwest direction draining 
into the Tarbella Dam Reservoir. 
Pine and Fir are the two main types of 
forests in the Siran Valley (Jan, 1982). The 
first type of forest is found in the elevation 
zones from 910 to 2273 meters (at the present 
time these forests are found on higher 
elevations in some areas because of forest 
clearing for agriculture). The constituent 
species are Chir Pine (Pinus roxburghii) and 
Blue Pine (Pinus wallichiana) which grow in 
almost-pure stands in two different elevation 
zones. Chir Pine grows from 910 to 1667 
meters. Blue Pine is found from 1818 to 2273 
meter elevations. In the lower transitional belt, 
Chir Pine grows mixed with subtropical dry 
evergreen species like Olive (Olea cuspidate), 
Phulai (Acaia modesta) and Sanatha 
(Dodonaea viscosa) from 910 to 1060 meters. 
In the upper transitional belt, Chir Pine is 
found mixed with Blue Pine from 1667 to 1970 
meter elevations. Chir Pine grows on warmer 
and drier aspects and Blue Pine on cooler 
aspects. Deodar (Cedrus deodara) is an 
associate specie with Blue Pine beyond 2273 
meter. The proportion of Deodar increases 
with increasing elevation. 
The component species of the Fir type