Abstract:
Zorit River is located in South West of Guna Mountain that is more of highly affected by
runoff. The increase in the cultivation of the highland areas of Zorit river watershed
increase degradation and erosion of upper parts of the river and also since there is
different land use practice on the upper part of the watershed which causes not
only degradation but also it causes shitting of river direction. The main objective of the
study is assessing channel morphology changes in Zorit River by evaluating the impacts
of land use land cover change (width, and channel length), identify the main cause of
channel morphology change in the river reach and indicate the downstream plan form
Zorit River. To see the change from the time series of the past river meanders and
changes Google earth pro was used. To compare the plan forms of Zorit River Current
River cross sections were taken at different intervals from Google earth and the past cross
sections were developed from the old topographic map of the study area. For the data
preparation Environment for Visualizing Images (ENVI 5.1) and Arc- GIS 10.8 were
used. The result of land use /land cover classification indicated that the forest land, shrub
land and bare land declined by 0.7 %, 7.4% and 1 % from 1990 to 2008, 2%,13.1% and
3.2% from 1990 to 2020 and 1.3%,5.7% and 2.2% from 2008 to 2020 while agricultural
land and built-up area was increased by 8.8 % and 0.4 % from the year 1990 to 2008
,17.9% and 0.4% from 1990 to 2020 and 9.1% and 0.1% from 2008 to 2020 respectively.
The channel shifts its direction 136 m to the left bank (east ward direction) and to the
right bank 145.27 m (westward direction). The Sinuosity index of Zorit River is 1.03,
1.02 and 1.03 in the year 1990, 2008, and 2020 between reach 1 and 2 respectively. This
revealed that the three years of river center line shows straight river channel pattern
downstream of the junction of the new river course to the past one. Hence, land use/ land
cover change and the increase in sinuosity index could affect the channel morphology
without manmade (hydraulic) structures like dams and bridge.
Key words: ‘Plan form change, GIS, watershed, Morphology, Zorit River’