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GIS techniques for carrying capacity study of Damodar River Basin
In addition to the above sources of
map data, specially prepared maps from other organistions participating in CCDRB
project have also been used. Map data prepared by the following organisations
has been used in the creation of DRB geographic database.
- Central Mining Research Institute, Dhanbad
- National Environmental Engineering Research Institute, Nagpur
- Centre for Inter-disciplinary Studies of Mountain & Hill Environment,
University of Delhi, New Delhi.
Any qualifying attribute data in
the printed maps used for creating DRB geographic database and related
publications of the respective agencies has been integrated with the spatial
data. Demographic data from census tracts has also been integrated at the block
and town levels of DRB. In addition, project specific data collected by the
following agencies has been integrated with maps of DRB.
- Central Mining Research Institute, Dhanbad
- National Environmental Engineering Research Institute, Nagpur
- Metallurgical and Engineering Consultants Ltd., Ranchi
- National Institute of Small Mines, Calcutta
- Indian School of Mines, Dhanbad
Macro Database
Creation
The broad methodology used to create digital data for DRB
thematic layers of the macro database is the following
- digitising of individual map sheet tiles
- construction of polygon topology wherever required
- editing of digitised themes
- association of names/attribute data with spatial features
- geo-referencing, mosaicking and edge matching of individual tiles
- clipping with DRB boundary
- symbolisation
Steps (a) to (d) complete the creation of
digital data for the individual tiles. Step (e) merges the individual tiles to
create a composite thematic layer for entire DRB area.. Step (f) eliminates
spatial features outside DRB area in the composite map. The final step
symbolises the map data by suitable coloring and symbol association. In the case
of satellite data, steps (a) to (d) above are replaced bu processing of imagery
and vectoristaion of the raster output.
Land
For land related
geographic data of DRB, thematic layers under the following categories were
created in the geographic database.
- DRB
- Administrative Units: Districts and Blocks
- Settlements
- Transport Network
- Slope
- Landuse Land Capability
- Soil
- Geology
- Geomorphology
- Agro-Ecology
- Ecology
The total area of DRB computed from the digital boundary
is 23,370.97 square kms and spans across two states, Bihar and West Bengal.
Digital data at two levels of administrative units, namely districts and block,
were created for DRB. Table 1 below lists the districts of DRB and area values
for each district within DRB.
Block boundaries are not available in SOI
1:250,000 sheets but can be found in maps published as part of District/Census
handbooks. These maps are not geo-coded and are not at a scale of 250,000, but
at varying scales depending upon the map. Block boundaries from district/census
handbooks were digitised and geo-referenced to the district boundary map. DRB
has a total of 99 blocks from the districts of Bihar and West Bengal.
The transport network of DRB comprises national highways, metalled and
unmetalled roads from SOI publications and railway lines, both broad and metre
gauges.
Table 1: Districts of
Damodar River Basin
District
|
State
|
Area within DRB
(sq
kms)
|
Dhanbad
|
Bihar
|
2996.8
|
Giridih
|
Bihar
|
5376.81
|
Hazaribag
|
Bihar
|
6631.53
|
Palamau
|
Bihar
|
736.97
|
Ranchi
|
Bihar
|
910.24
|
Santhal Pargana
|
Bihar
|
571.05
|
Bankura
|
West Bengal
|
1564.67
|
Burdwan
|
West Bengal
|
2113.61
|
Howrah
|
West Bengal
|
726.16
|
Hooghly
|
West Bengal
|
359.87
|
Purulia
|
West Bengal
|
1383.26
|
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