GIS based land use planning for watershed management
Loading...
Date
2012
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
YSPU
Abstract
The present study was conducted in ‘Sd4e’ sub-watershed of Gambhar catchment located at 31
o
00’ to 31
o
03’N
latitudes and 77
o
00’ to 77
o
06’E longitudes in Solan district of H.P. India with the aim to analyse its land use through GIS
and assess phytosociological attributes, biomass and carbon stock of vegetation in forests/grasslands at different elevations
during the years 2007 and 2008. The sub-watershed was delineated into three elevations a) E1
(850-1150m b) E
2
(1150 -1600m) and c) E
3
(1600m & above). There are 26 villages in the sub-watershed of which five are located at E1
, 20 at E
2
and
01 is located at E
3. Population density in the sub-watershed is 210 persons/km
2
and sex ratio is 988. Reclassified DEM of the
sub-watershed revealed that 31.38% area is in elevation E
1
, 42.86% in elevation E
2
and 25.76% in elevation E3
. 80.97% area
of the sub-watershed is under steep slope greater than 25
0
, 5.64% area is under moderate slope of 5-15
0
and 4% area is levelland with gentle slope of 0-5
0
. Hydrology model suggested that water flow accumulation is high in the villages like Garu,
Kashmari, Chiyaman, Lachog and Nalkagaon whereas, moderate accumulation of water occurs in areas like, Damehar,
Denwanda, Banota and Gandrori. NDVI maps indicated that the vegetation has increased in the area from 1998 to 2010.
Land use change from 1998 and 2010 showed that areaunder dense and sparse forests have increased by 6.58%. Scrubland
and grassland area has decreased by 2.49% and 3.54%. Infrastructure has increased by 4.75% whereas cultivated area has
decreased by 6.62% while barren land marginally increased by 1.32%. The sub-watershed nurtures varioustypes of forests at
different elevations. Nine forests viz., chir pine,mixed and khair forests at elevation E1
, chir pine, mixed and ban-oak forests
at elevation E2
and ban oak, mixed and chir pine forests at elevation E
3
were selected for vegetation analysis. At each
elevation one grassland site was also selected to compare its vegetation with forests. In all, 61 plant species in which 7 trees,
25 shrubs, 21 grasses, 2 sedges, 2 forbs and 4 legumes were recorded in the study sites. The density, basal area and biomass
of herbage vegetation under different forests/grasslands at all the elevations increased gradually with the onset of rainfall in
July and attained their peak values by August/September. The density, basal area and biomass of herbage vegetation under
different forests/grasslands at all the elevations increased gradually with the onset of rainfall in July and attained their peak
values by August/September. The peak density and basal area of herbage in grasslands ranged from 649.60 to 1347.90
tillers/m
2
and 29.99 to 65.70 cm
2
/m
2
while, in different forests it varied from 351.20 to 1005.30tillers/m
2
and 14.87 to 43.94
cm
2
/m
2
. Biomass of herbage in grassland vegetation fluctuated from 1.785 to 5.402 t/ha and under different forests it ranged
from 0.637 to 4.657 t/ha. Total biomass (aboveground and belowground biomass of herbs + shrubs + trees) in
forests/grasslands at elevation E
1
showed the precedence: chir pine forest > mixed forest > khair forest > grassland. At
elevation E2
it was in the order: mixed forest > ban oak forest> chir pine forest > grassland and at elevation E
3
: ban oak
forest > mixed forest > chir pine forest > grassland. Total biomass in forests ranged from 116.97 to 459.9 t/ha. Carbon stock
accumulation in different forests/grasslands at elevation E1decreased in order: chir pine forest > mixed forest > khair forest
> grassland, at elevation E
2
it was in the order: mixed forest > ban oak forest> chir pine forest > grassland and at elevation
E
3
: ban oak forest > mixed forest > chir pine forest> grassland. Total carbon stock in forests (herbs + shrubs + trees) ranged
from 56.40 to 224.67 t/ha. Grasslands at different elevations produced around 1/5 to 1/22 of the carbon stock in forests
Description
Keywords
Watershed management, GIS, Land