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of land transformation process land-use interpretation was carried out
for the years 1990 and 2010 using IRS LISS-III and PAN merged data for
the respective years. The exercise revealed that oak and pine forests have
decreased respectively by 25 % (4.48 km
2
) and 3% (.28 km
2
) thus bringing
a decline of 4.76 km
2
forest in the watershed during 1990 to 2010. But, due
to climate change the mixed forest taking place of oak forest in certain
pockets and consequently the mixed forest in the catchment increased by
18 % (2.3 km
2
) during the same period which reduced the overall loss of
forests in the region but it is not eco-friendly as the oak forest as the broad
leaved and wide spread roots of oak trees helps in controlling the several
hydrological hazards such as accelerated runoff, erosion, landslides, fl ash
fl ood and river-line fl ood during monsoon period and drought during
non-monsoon period. As a result, the watershed recorded a total decline
of 2.46 km
2
or 6% forest area during 1990 to 2010 (Table 11.3 and Fig. 11.3).
The non-forest area has increased dramatically due to lopping and cutting
of trees, accelerated runoff, soil erosion, and growing agricultural activities.
The non-forest area has mainly been confi ned to barren land, riverbed and
cultivated land. Barren land increased 1.21 km
2
(56%), riverbed increased
0.78 km
2
(52%) and cultivated land increased about 0.63 km
2
(3%) during
the period of 1990 to 2010 (Table 11.3 and Fig. 11.3). The results of land-use
dynamics presented on Table 11.4, advocate that the overall accelerating
factor of land-use dynamics in the study area broadly categoriezed as a
dominant and supporting factor. Out of the total seven classes of the land
use-land cover, fi ve classes (i.e., oak, pine, mixed, barren and riverbed) are
changing dominantly due to the climate change factor and anthropogenic
factors play a supporting role whereas only two classes (scrub land and
agricultural land) are changing dominantly by anthropogenic factors and
climate change factors play a supporting role. Expansion of mixed forest
land brought out due to upslope shifting of existing forest species because
of the climate change factor, only because upslope areas are getting warmer
than in the past with the rate of 9ºC-12ºC/two decades (Table 11.3 and Fig.
11.3).
Geo-hydrological impacts of accelerated land use degradation
Increasing rates of land-use degradation due to climate change accelerating
several geo-hydrological hazards in the Himalaya. The major geo-
environmental impact is deforestation and land degradation which trigger
several hydrological hazards during the monsoon and non-monsoon
seasons. The major non-monsoon hydro-hazards are decreasing the
underground water table, drying up of natural water springs and decreasing
trends of streams discharge whereas monsoon hydro-hazards found high
monsoon runoff, fl ash fl oods, river-line fl oods, soil erosion and non-seismic
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