577
5. The wetlands are mapped often by using
IRS P6 LISS III data. They provide data in
four spectral bands: green, red, near-infra
red (NIR) and short-wave infrared (SWIR),
with 23.5-m spatial resolution and 24-day
repeat cycle. The spatial resolution is suitable for 1:50,000 scale mapping. The state
of Assam, for example, is covered in 17 IRS
LISS III scene.
6. Some amount of fi eld observations, called
‘ground truth’, are required in RS techniques, in order to convert into meaningful
information. Such work involves visiting a
number of test sites, usually taking the satellite
images. The location of the features is
recorded using the GPS.
7. Standard Survey of India (SOI) topographical maps are generally used for reference
purpose. Lineage data of National Wetland
Maps at 1:250,000 scale are used for
reference.
8. The mode can be geostationary, permitting
continuous sensing of a portion of the earth
or sun‐synchronous with polar orbit covering
the entire earth at the same equator crossing
time. The Landsat series of satellites have a
repeat period ranging from 16 to 18 days,
whereas in the case of IRS, it is 22 days.
Satellites cover the same area and provide
continuous coverage of a fi xed area.
9. A GIS is a system of software and procedures to facilitate the management, manipulation, analysis, modeling, representation
and display of geo‐referenced data to solve
complex problems regarding planning and
management of resources.
10. A function of an information system is to
improve one’s ability to make decisions. An
information system is a chain of operations
starting from planning the observation and
collection of data, storage and analysis of the
data, to the use of the derived information in
some decision-making process. A GIS is an
information system which is designed to
work with data referenced to spatial or geographical coordinates.
11. Standard methodologies are adopted in GIS
works.
(a) Database creation and organisation
through generation of spatial framework in
GIS environment, (b) geo-referencing of
satellite data, (c) identifi cation of wetland
classes as per the classifi cation system given
in a standard (e.g. NWIA) manual and mapping of the classes using a knowledge-based
digital classifi cation and on-screen interpretation, (d) generation of base layers (rail,
road network, settlements, drainage, administrative boundaries) from satellite image
and ancillary data, (e) mosaicing/edge
matching to create database at different
levels, (f) coding of the wetlands following
the standard classifi cation system and codification as per the (NWIA) manual and
(g) preparation of map.
12. In this step, the raw satellite images are
converted to specifi c map projection using
geometric correction. This is done using
archive geometrically corrected LISS III data
(ISRO- NRC land use/land cover project).
Standard image processing softwares are
used for geo-referencing.
13. The wetlands are delineated through image
analysis. These formed the foundation for
deriving all wetland classes and results.
Consequently, a great deal of emphasis had
been laid on the quality of the image
interpretation.
14. Upon completion of the inventory stage,
complex queries on multiple layers can be
performed using spatial and aspatial analysis
techniques.
15. More advanced spatial and modeling techniques are required to support the decisions
of managers and policymakers. This involves
shifting of emphasis from basic geographical data handling to manipulation, analysis
and modeling in order to solve real-world
problems.
16. There are also alternative methodologies in
GIS technology.
17. Microwave remote sensing tools have an
important role to play in applications relating to wetland monitoring and mapping. In
optical RS, the visible and infrared part of
the electromagnetic spectrum is used to
26.13 Inference
5. The wetlands are mapped often by using
IRS P6 LISS III data. They provide data in
four spectral bands: green, red, near-infra
red (NIR) and short-wave infrared (SWIR),
with 23.5-m spatial resolution and 24-day
repeat cycle. The spatial resolution is suitable for 1:50,000 scale mapping. The state
of Assam, for example, is covered in 17 IRS
LISS III scene.
6. Some amount of fi eld observations, called
‘ground truth’, are required in RS techniques, in order to convert into meaningful
information. Such work involves visiting a
number of test sites, usually taking the satellite
images. The location of the features is
recorded using the GPS.
7. Standard Survey of India (SOI) topographical maps are generally used for reference
purpose. Lineage data of National Wetland
Maps at 1:250,000 scale are used for
reference.
8. The mode can be geostationary, permitting
continuous sensing of a portion of the earth
or sun‐synchronous with polar orbit covering
the entire earth at the same equator crossing
time. The Landsat series of satellites have a
repeat period ranging from 16 to 18 days,
whereas in the case of IRS, it is 22 days.
Satellites cover the same area and provide
continuous coverage of a fi xed area.
9. A GIS is a system of software and procedures to facilitate the management, manipulation, analysis, modeling, representation
and display of geo‐referenced data to solve
complex problems regarding planning and
management of resources.
10. A function of an information system is to
improve one’s ability to make decisions. An
information system is a chain of operations
starting from planning the observation and
collection of data, storage and analysis of the
data, to the use of the derived information in
some decision-making process. A GIS is an
information system which is designed to
work with data referenced to spatial or geographical coordinates.
11. Standard methodologies are adopted in GIS
works.
(a) Database creation and organisation
through generation of spatial framework in
GIS environment, (b) geo-referencing of
satellite data, (c) identifi cation of wetland
classes as per the classifi cation system given
in a standard (e.g. NWIA) manual and mapping of the classes using a knowledge-based
digital classifi cation and on-screen interpretation, (d) generation of base layers (rail,
road network, settlements, drainage, administrative boundaries) from satellite image
and ancillary data, (e) mosaicing/edge
matching to create database at different
levels, (f) coding of the wetlands following
the standard classifi cation system and codification as per the (NWIA) manual and
(g) preparation of map.
12. In this step, the raw satellite images are
converted to specifi c map projection using
geometric correction. This is done using
archive geometrically corrected LISS III data
(ISRO- NRC land use/land cover project).
Standard image processing softwares are
used for geo-referencing.
13. The wetlands are delineated through image
analysis. These formed the foundation for
deriving all wetland classes and results.
Consequently, a great deal of emphasis had
been laid on the quality of the image
interpretation.
14. Upon completion of the inventory stage,
complex queries on multiple layers can be
performed using spatial and aspatial analysis
techniques.
15. More advanced spatial and modeling techniques are required to support the decisions
of managers and policymakers. This involves
shifting of emphasis from basic geographical data handling to manipulation, analysis
and modeling in order to solve real-world
problems.
16. There are also alternative methodologies in
GIS technology.
17. Microwave remote sensing tools have an
important role to play in applications relating to wetland monitoring and mapping. In
optical RS, the visible and infrared part of
the electromagnetic spectrum is used to
26.13 Inference