Global Change and Mountains: Consequences, Responses and Opportunities - Impact of Global Changes on Mountains: Responses and Adaptation - page 105

carried out in the region revealed that the amount of surface runoff from
cultivated and barren lands is much higher compared to the amount of
runoff from other categories of land, particularly, forests and horticulture
(Tiwari 1995, 2000, 2008, Rawat 2009).
The large-scale depletion of forest resources is causing great damage to
the underground water resources by reducing the water-generating capacity
of land to springs and streams in the region. Since, a large proportion of the
rainfall is lost through surface run-off without replenishing the groundwater
reserves, a large number of springs that support a variety of life-sustaining
activities are drying up fast in the region. The water resources of the region
are diminishing and depleting fast owing to the rapid land-use changes
and resultant reductions in groundwater recharge (Tiwari and Joshi 2012a,
Valdiya and Bartarua 1991, Tiwari 1995, 2000, Bisht and Tiwari 1996,
Wasson et al. 2008, Jianchu et al. 2008). In the Himalaya, these hydrological
imbalances are discernible in terms of:
1. The long-term decreasing trend of stream discharge (Tiwari and Joshi
2012a, Rawat 2009, Tiwari 2008);
2. Diminishing discharge and drying up of springs (Valdiya and Bartarya
1991, Rawat 2009, Tiwari 1995, 2000, 2002, 2008, 2010, Tiwari and Joshi
2012a, Tiwari and Joshi 2005, 2007, 2009);
3. Human impacts on surface run-off fl ow systems and channel network
capacity (Tiwari and Jangpangi 1962, Rawat 2009).
In addition to above-mentioned hydrological implications, the natural
risks of rapid land-use changes in the Himalaya are also clearly discernible
in terms of the dwindling capacity of lakes situated in and around the urban
areas through their accelerated silting and pollution in the region (Khanka
and Jalal 1984, Rawat 2009). Bathymetric investigations of Bhimtal and
Nainital Lakes situated in the Kumaon Himalaya revealed that the capacity
of these important lakes has respectively decreased by 5494 m 3 and 14150
m 3 during the last 100-110 years due to rapid siltation of the lakebeds. The
annual average rate of siltation in the Nainital Lake was 65.32 m 3 (Khanka
and Jalal 1984, Hashimi et al. 1994). Most of the lakes of the region are
heavily infested by weeds and invaded marshy conditions (Valdiya and
Bartarya 1991).
Rapid commercial and residential land development throughout the
North American Rocky Mountains has caused signifi cant, but poorly
assessed, ecological and social effects (Theobald et al. 1996). British Columbia
is a mountainous province, and most of its geographical area lies in high
Rocky and coastal mountain ranges which are among the youngest and
recent mountains systems of the Earth. Consequently, these vast mountains
tracts are geologically instable and ecologically vulnerable (Robinson 1991).
In the Canadian Rockies and coastal mountains in British Columbia the