MONITORING OF URBAN SPRAWL AND SPATIO-TEMPORAL VARIABILITY OF
LANDUSE/LANDCOVER CHANGE IN ASAN WATERSHED, DOON VALLEY, UTTARAKHAND,
INDIA
Abstract
Urban expansion is a global trend primarily determined by
overpopulation, particularly in developing countries like India. The
pattern and boundary of urban expansion could be observed and modelled
on a Spatio-temporal dimension in the Asan watershed, situated in
western Doon Valley, Uttarakhand, India. The specific objectives of the
present study are: 1) Monitoring Land Use Land Cover (LULC) change
detection and its impact on the hydrological regime of the watershed, 2)
Generation of urban growth pattern map to identify the urban expansion
along with the directions and distance from the watershed centroid. To
achieve the objectives, the four LULC maps of different years are
generated through Landsat and LISS-IV dataset from 1980 to 2016. The
eight classified classes of LULC includes: build-up (urban and rural),
cropland, fallow land, plantation, evergreen needle leaf forest,
deciduous broadleaf forest, mixed forest, and water bodies. The LULC
change analysis concludes that the built-up area continuously expanding
at an alarming rate, nearly four folds in the last 36 years. The major
areal portion of cropland and plantation are converted into build-up at
a faster rate after 1995 whereas the areal extent of water bodies are
also reduced. Based on monitoring of urban growth, the wind rose tool
revealed that the southwest direction is the dominant direction of the
urban expansion till 1980 and 1980-1995 which contribute 48% and
47.61% respectively of the total urban area of the watershed. However,
in the period 1995-2008 and 2008-2016, the eastern direction is
predominant, which contribute 36.44% and 35.27% respectively from the
total urban areal expansion. This reflects a situation where the eastern
direction is expected to dominate in the next years. Consequences of
urban expansion create pressure on the into the watershed which leads to
degradation of natural resources, forest environment and hydrological
elements of the watershed.