Micro-watershed development plans using Remote Sensing and
GIS for a part of Shetrunji river basin, Bhavnagar
A. K. Sharma and R. R. Navalgund
Space Applications Centre, Ahmedabad.
A. K. Pandey and K. K. Rao
U. T . D. Barkatullah Vishwavidhyalaya, Bhopal
Micro-watershed level planning requires a host of inter-related information to be
generated and studied in relation to each other. Remotely sensed data provides valuable
and up-to-date spatial information on natural resources and physical terrain parameters.
Geographical Information System (GIS) with its capability of integration and analysis
of spatial, aspatial, multi-layered information obtained in a wide variety of formats
both from remote sensing and other conventional sources has proved to be an effective
tool in planning for micro-watershed development. In this study an approach using remote
sensing and GIS has been applied to identify the natural resources problems and to
generate locale specific micro-watershed development plans for a part of Shetrunji
river basin in Bhavnagar district, Gujarat. Study of multi-date satellite data has
reveled that the main landuse /landcover in the area is rainfed agriculture, wasteland
with/without scrubs in the plains and undulating land and scrub forests with forest blanks
on the hills. Due to paucity of ground water for irrigation, the rainfed agriculture area
lacks sufficient soil and moisture to support good agriculture. The agriculture areas along
the streams are constantly washed and undergo sheet erosion, thus converting valuable
agricultural land into unproductive wastelands. For a major part of the year, the hills
remain barren except for few small areas displaying a variety of thorny scrubs and few
scattered trees growing along the less assessable slopes. Few varieties of grasses also
spring up during the monsoon. The degraded ecosystem has affected the life of the residents
within the micro-watersheds. There is always a scarcity of fuel, fodder and water for
drinking and domestic use. The depleting vegetation cover has resulted in excessive soil
erosion exposing barren rocky wastes. The steep rocky hill slopes facilitate high runoff
leading to poor ground water recharge and increased siltation in the village tanks and
ponds. According to the local people even today shepherds from adjoining taluka regularly
visit to graze hordes of sheep and cattle. In addition to this thereis the problem of the
ever-increasing human and livestock population. Thus a heavy pressure exists on the scarce
biotic resources of the study area. The main actions suggested for development of land
and water resources in the area are being implemented by Mahajanam in consultation with
Study area details
The study area covering 34 micro-watersheds (28,250 ha.) is a part of Shetrunji river basin
in Bhavnagar district, Gujarat and is located between longitude 710 42' &
710 55' East and latitude 210 20' & 210 35' North.
Encompassing Palitana town and 20 other villages with a total population of 69,428 heads
(Census, 1991) it receives 454 mm of average annual rainfall. The Shetrunjay hills and the
Hastigiri hill are two prominent hills in the study area. The Shetrunjay hills about 603
m above mean sea level (amsl) and Hastigiri hills, 431 m (amsl) with ancient temples are
places of religious and tourist interests.
indian Remote Sensing Satellite (IRS) LISS-III data at 1:50,000 and 1:25,000 scale of
December 1996, January and April 1997 and October, 1988 and collateral data such as
Topographical maps at 1: 50,000,Geological / Hydrogeological,Water level and quality
maps climate, rainfall data and Census data, etc. have been used
The methodology comprises an integrated approach using multi-date satellite datafor
preparation and study of multi-thematic maps at 1:50,000 scale namely Hydrogeomorphology,
landuse/landcover (1:25,000 scale), soil, slope, ground water level and quality, etc.
Based on subject domain decision rules for land and water management,the integration
of the natural resources and demographic theme has been carried out in GIS to identify
the problem areas and to providing prescriptions for solving them. The action plan maps
thus generated were consequently validated in the field in consultation with local
experts. Action plan maps for selected 18 microwatersheds (13940.29 ha.) have been
generated at 1:25,000 scale using PAN+LISS III merged data where implementation of plans
is to be carried out by Mahajanam.
Theme map details
The details of different theme maps prepared are as below
The hydrogeomorphological map comprised seven landform types namely flood plain (7.69 % area),
denudational hills (15.10 % area) and residual hills (0.45 % area) over basalt, pediments
(2.07 %), buried pediments (64.97 %) and valleys (5.55 %) dissected plateau (4.16 %) and
lineaments. The ground water prospects within different landforms vary from good in the
plains and valleys to poor and poor to nil in the denudational hills and residual hills.
Landuse /land cover classification using kharif, rabi and summer season satellite data
reveled the spatial extent of built up land (3.42 %), forest land (16.88 %), agriculture
land (66.85 %), waste land (12.15 %) and others like waterbodies/ stream (0.70 %) etc.
The forestland comprised scrub forest (4.08%) and forest blanks (12.80 %). Further
classification of forest blanks as forest blanks with good grass (4.37 %), moderate
grass (4.84 %) and poor grass (3.60 %) was possible.
Surface water body, drainage and watershed map showing all 34 micro-watersheds and
average slope map with seven slope categories have been prepared using SOI topographical
maps with 20m contour interval.
The soil map obtained from National Bureau of Soil Survey and Landuse Planning (ICAR),
Nagpur showed soils of hilly terrain, soils of pediments and soils of piedmont plains
belonging to six series.
Analysis of 17 year (1980 to 1996) monthly rainfall data for five stationswas carried out.
The area receives 454 mm average annual rainfall with 25 rainy days.