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MAPPING AND CARTOGRAPHY
FROM SATELLITE
CHALLENGES AND PERSPECTIVES
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Prof. U.
R. Rao
Member, Space Commission
Bangalore-560 094, India.
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1.0
Introduction
Since the beginning of civilisation, amps have been
the most effective means of describing events and information. The term
map has its genesis in the Latin word "Mappa" which means a
piece of table cloth or a napkin, used as parchment roll by Greeks and
Romans for preparing their maps during warfare. Sketchy maps and
illustrations used to record land ownership and revenue information in
the past, later gave rise to cadastral maps. Assessment of crop yield and
fixing the governmental share became a major activity of revenue
administration, which depending upon the whims and fancies of jagirdars
often resulted in a tussle between the peasantry and the
revenue-collectors. The credit for systematizing the revenue collection
system goes to Todar Mul, who as the Revenue Minister under Akbar, evolved
new arrangements for revenue administration, including authoritative
patta preparation. Since the early roots of the modern day cadastral maps
owe their origin to Todar Mul Bandobast, it is only natural that this
prestigious annual memorial lecture of INCA is named after this legendary
figure.
With the passage of time and the discovery of
printing paper, map making achieved a new dimension - permitting the
inclusion of additional information as charts and symbols leading to the
birth of a separate discipline - Cartography. Cartographic conventions
have evolved over the centuries, reflecting the development of our
civilization and culture and responding to the challenging demands for
authentic geographic information systems. Over the years, it has undergone
major transformations, from maps portraying topographic description of
the terrains, to the inclusion of thematic mapping, dealing with the
statistically derived information on various relevant dynamic resources.
Transition in mapping from the historical artistic portrayal to the
complex thematic cartography has been the natural evolution, which is as
much due to the availability of better information as due to the
development of computerised cartography techniques, which have made it
possible to represent data and information in digital formats for
processing in the computer using specialised software packages. With the
availability of satellite-based remote sensing data on resources over
large areas in real time replacing tedious ground based and aerial
surveys, and development of the Global Positioning System (GPS)
integrated into the inertial platform and cameras, the dream of
cartographers to carry out thematic mapping without the use of time
consuming ground surveys became a reality.
Historically beginning with the clay tablet
inscription of the Babylonian era in 2500 BC, map making on a two
dimensional surface was extensively practiced by the ancient
civilisations in Egypt,
India and China. It
was however left to the great astronomer Nicolaus Copernicus, who with
his astronomical observations correctly hypothesized the earth as a near
spherical planet circling around the Sun in a circular orbit, to put
cartography in its proper perspective. In spite of the great impetus to
cartography provided by the military commanders and civil engineers, the
non-availability of maps with high precision was a distinct disadvantage.
I leave it to the imagination of the learned audience on the consequences
to the world of today if Columbus, through
mistaken understanding, had not discovered America five hundred years
ago. The advent of space era has totally revolutionised the science of
cartography by making it possible to repetitively monitor the physical
resources of our planet in real time to enable the mapping of dynamic
changes.
Cartography has now evolved into a multifaceted
discipline encompassing a body of techniques for representing a variety
of information and their spatial as well as temporal relationships.
Involvement of scientists and technologists belonging to a number of
disciplines has vastly enriched the science of cartography. Perceptions
of cartography may differ while mathematicians see it as a branch of
applied mathematics, image analysts view it as an outcome of image
processing techniques. Computer scientist may see cartography as
challenge in graphics and software-based representation;
photogrammetrists and surveyors may see it as a technique to accurately
represent earth's geodesic features and precisely measure geographical
features. Planners on the other hand are bound to use cartography as it
has developed in the recent past, for displaying and retrieving
developmental information.
Parallel technological developments in data capture
methods and production technology, have resulted in unprecedented
progress altering the concept of cartography resulting in the inclusion
of digital mapping, satellite imaging, digital image analysis, geographic
information systems and more recently global positioning systems. New map
products have appeared in the form image maps, holograms, three dimension
stereo on video terminals and digital file stored on compact discs. The
main impact of these developments has been to change conventional
cartography into a multi-faceted modern discipline responsive to the
needs of the dynamically changing world scenario.
The process of map making encompasses two distinct
parts - the first is concerned with the preparation of a variety of
accurate and precise maps used for basic reference and control such as
large-scale topographic maps of the land which are used for a variety of
resource applications like hydrographic mapping, soil mapping, geological
mapping, aeronautical charts etc., the second refers to preparation of
larger variety of maps used for general and educational purposes, mainly
the small scale thematic maps used as Atlases, road maps, administrative
maps etc.
The evolution of parametric mapping in conjunction
with the developments in computer technology and statistical techniques
have for the first time enabled cartographers to respond to the
challenges of geo information engineering. The introduction of digital
technology has in addition to making it possible to represent terrain
geomorphological features using digital elevation models, has enabled the
representation of a variety of thematic features on a digital base which
can then be manipulated by the planners for accurate representation of
the dynamic changes in thematic cartography. The ability to tap a variety
of databases, to store such information between different agencies and
integrate the totality of information, which form crucial elements of the
Geographic Information System (GIS), is the most powerful attribute of
digital cartography. This in turn, has necessarily led to the definition
of minimum standards for data models and exchange formats and even the
use of expert system for timely extraction of basic information required
by individual users. In this talk, I propose to briefly address the
impact of satellite technology on cartography and how the two together
have responded to the need for accurate mapping and quick retrieval of
thematic information towards initiating developmental processes.
The importance of thematic maps which integrate
information on all economic and social factors of importance and their
geographical distribution, for initiating region specific developmental
activities was first recognised by Finland as early as 1899.
Since then, the movement of thematic cartography has spread all over the
world, albeit slowly, from 12 countries in 1960 to over 100 countries in
1990s. The availability of a variety of resource information from space
based platforms has made thematic maps, our basic tool for carrying out
most of the human activities in a systematic scientific manner. These
include:
Modernisation, expansion, upgrading and development of transportation
means, including roads, railways, ports and airports
Solving problems of rural to urban migration
Security and defence related activities such as definition of national
boundaries, exclusive economic zone (EEZ), emergency and relief measures
under disaster situation.
Development of power and telecommunication networks
Agricultural management and development of irrigation and water supply
Protection of environment from ecological disasters such as flooding,
desertification and erosion.
Landuse, land management
Exploitation of non-renewable resources
Provision of cultural and social services
2.0 The Global Status of Mapping
In spite of the significant efforts made by
surveyors/cartographers world over, large scale topographical maps are
not available for many areas of the world. The lack of detailed
topographical maps of the global landmass is a serious gap in the
existing information system. Most developed countries such as North America and European countries are well
mapped at various scales ranging from the most accepted scale of 1:50,000
and 1:25,000 to larger scales of 1:5,000 and 1:10,000. On the other hand,
the developing countries, with agro-based economies are yet to be fully
mapped even at the basic scale of 1:50,000. UN Global statistical data of
1989, clearly brings out, as seen in Table-1, the slow progress in
mapping, particularly in large areas in Africa, Latin America and Asia, which are yet to be mapped on a larger scale.
Table-1
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Scale
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Coverage (%)
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Annual Progress (%)
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1:25,000
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13
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0.3
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1:50,000
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42
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1.2
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1:100,000
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42
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0.8
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1:200,000
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80
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-
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The updating of the maps worldwide
are far from satisfactory with only 3% of the maps being regularly
updated. The reasons for the serious lacuna in the availability of the
detailed topographical maps especially in the developing countries are:
a) Lack of regular and detailed surveys of the entire
land mass excepting in a few selected regions in the advanced countries
b) Non-existence of a mechanism for regular updation
of these maps due to the large lead time required for planning and
carrying out aerial and ground based surveys.
c) Non-standardisation of mapping scales, legends,
projection ;formats, etc.
d) Lack of automation for handling large volume of
digital data
e) Limited organizational capabilities and lack of
financial resources
In spite of the recognition of the importance of
mapping at scales of 1:1,00,000 or large for carrying out developmental
activities and exploitation of natural resources, complete coverage of
the earth even at the coarser scale is expected to take 100 years at the
present scale of progress. The only way to avert this situation is to
considerably increase the rate of mapping and map revision through
increased application of remote sensing technology.
3.0 Satellite Remote Sensing and Thematic Mapping
Satellite based Remote Sensing has become an
invaluable source of spatial data on natural resources which can provide
timely information on their present status as well as their dynamic
changes. Remotely sensed satellite imageries provide the most authentic
information to map and monitor land features, natural resources and
dynamic aspects of human activities needed for the preparation of
thematic resource maps. Stereoscopic RS data are now available which are
best suited for generating Digital Elevation Models (DEM) to extract
elevation information at desired scales. The availability of a number of
remote sensing satellites such as IRS (India), LANDSAT (USA), SPOT
(France), MOS-1 (Japan), ERS-1 (ESA) providing continuous data has
greatly helped in the development of modern cartography, facilitating
timely mapping and change detection in a variety of application areas -
agriculture, hydrology, geology, drought and flood monitoring, marine
studies, snow studies, land use mapping, urban growth analysis etc.
Table-2 provides an overview of mapping activities carried out in
different countries using RS data.
Rapid developments during the last three decades
have led to the formulation of operational procedures for utilising
remote sensing data for various resources management activities.
Extensive use of data from the Indian Remote Sensing Satellites - IRS-1A
and IRS-1B by the Department of Space (DOS), along with concerned user
departments/agencies' has enabled operational use of RS techniques in a
number of national-level projects in different resource management areas
covering diverse themes such as forestry, wasteland mapping, agricultural
crop acreage and yield estimation, monitoring and management of flood and
drought disasters, landuse/land cover mapping, wasteland mapping, water
resources management, groundwater targeting, marine resources survey,
urban planning, mineral targeting and environmental impact assessment.
Table-2 provides an overview of the utilisation of RS data in various
developing countries of the world. Thus, Satellite data forms the basic
input for the preparation of thematic cartographic maps which are
essential for planning developmental activities of a region.
3.1 Forestry Preparation of forest maps on 1:25,000
scale for the entire country, using satellite data of 1972-75 and 1985-87
was one of the first projects to be carried out in India, which clearly brought
out the reduction in the closed forest cover from 14% to 11% of the
geographical area during the period. Awareness of depletion of forest
cover brought out by the thematic forest maps enabled the execution of
necessary corrective measures resulting in 0.5% increase in the forest
cover as observed in 1989-91, in spite of the serious deficit in fuel
wood on a country wide basis. Selected forest areas have also been
thematically mapped for identifying forest types, biomass assessment and
monitoring of forest plantation etc., at scales of 1:50,000. The fact
that the annual sedimentation load carried by Indus, Ganges and Brahmaputra rivers alone, is almost 2,400 m.t., one
third of the total sediment carried by all the rivers in the world, is a
striking evidence of the serious soil erosion problem in hilly areas of
the country resulting from extensive deforestation. It is only through
repetitive and constant monitoring of forest cover that we can hope to
arrest this large scale depletion of top soil.
3.2 Wasteland Mapping A nationwide wasteland mapping
on 1:50,000 scale has been carried out for the National Wasteland
Development Board. Actions have been initiated by concerned developmental
sectors of the country to reclaim the culturable waste lands which
account for almost 25 m.ha. through afforestation, fodder development and
appropriate agricultural practices. In the context of providing food
security to the growing population, reclamation of cultivable wastelands
for productive use assumes a great significance.
3.3 Landuse Mapping A major project at National
level, for generating districtwise landuse/land cover information on
1:250,000 scale using IRS data for spatial planning and management of
lands under different agroclimatic zones, has been completed. This study,
for the first time brought out accurate information on agricultural
landuse including cropping pattern, fallow lands, surface water bodies
etc., which are valuable inputs to the decentralised five yearly planning
process of the country. Detection of rapid depletion of pasture lands,
increase in the fallow lands, vanishing of surface water bodies and
general degradation of large tracts of once productive lands have firmly
established the need for continuous monitoring of land usage and timely
preparation of thematic maps.
3.4 Soil Mapping Satellite remote sensing has been
utilized for preparing small scale soil resource maps of the country.
Preparations of maps showing details like soil classification and land
capability have been taken up for selected areas, to assist in optimal
agricultural development in these areas.
3.5 Groundwater targeting Space remote sensing has
been very effectively used in India for identifying
prospective groundwater zones for optimal exploitation of ground water.
Using hydrogeomorphological maps, prepared on 1:250,000 scale using
satellite data, groundwater potential zones could be delineated. Over
200,000 borewells have been drilled in about 160,000 problem villages of
the country using space remote sensing inputs. A sample analysis of over
17,000 wells drilled initially had established a success rate of 92% as
against 45% achieved using conventional mehthods.
3.6 Flood Mapping Satellite remote sensing is being
successfully used in the country for obtaining near real-time information
about areas affected by floods in all the major flood-prone river basins
(Brahmaputra, Ganga, Kosi, Godavari
etc.). Repetitive monitoring of the flood inundation pattern over the
years has helped delineation of areas prone to perennial flood-risk, for
taking long-term flood control measures like providing embankment and
identifying vulnerable areas likely to be affected by the meandering
rivers causing extreme risk to lives and livestock. Quantitative
estimation of the damage to agricultural crops and other infrastructural
facilities due to floods are also routinely assessed. Use of ERS-1 data
has added a new dimension by enabling the monitoring of flood affected
areas under cloud cover.
3.7 Geological Mapping A number of remote sensing
based studies have been carried out in the country for geological
applications in general and specifically for delineating areas having
potential new mineral sites. One of the major projects carried out for
identifying areas for mineral search at regional level using 1:100,000
scale maps, was in the South Indian Peninsular shield, covering an area
of 400,000 sq.km. under the project Vasundhara. A systematic digital
geo-scientific data base has helped in arriving at certain promising
target sites for further exploration. Likewise target areas for mineral
exploration (base metals, tin, iron-ore, bauxite in about 1,00,000
sq.km., in Orissa State), oil exploration (in North-Eastern and
Southern parts of India)
and radioactive minerals (in Western, Central, South-Western and Northern India) have also been identified using
satellite remote sensing.
3.8 Urban Planning Practically all the major cities
in the country with more than 1 million population, have been mapped on
1:250,000 and 1:50,000 scales to monitor the rapid changes taking place
in the urban expansion, a basic input required for respective planning of
mega cities. GIS based studies for the Bombay Metropolitan Region and the
National Capital Region (Delhi)
have demonstrated the utility of the multi-parameter data-base in
arriving at useful guidelines for urban planning including siting of
drainage facilities with appropriate capacity to meet the future growth
requirements. Remote sensing has also been successfully applied to align
road/rail in the country, as in the case of ring-road alignment for Bangalore city at a
fraction of a cost and time compared to conventional methods.
3.9 Coastal Mapping Entire Indian coastline has been
mapped on 1:50,000 scale using satellite data with regard to coastal
landforms, landuse and land cover. Prospective sites for aquaculture have
been identified besides apprising aspects like suspended sediment
dynamics, coastal currents, near-shore bathymetry, areas under mangroves
etc., thus providing inputs for better management of the coastal areas.
In the context of the limited capability to increase marine fishery
potential and the need for improving aquaculture to meet proteing demands
of the growing population, coastal mapping becomes very important.
Preliminary maps showing the extent of coral reefs have also been
prepared using IRS data.
3.10 Fisheries Prospect Mapping Fisheries prospect
charts are prepared routinely, using NOAA data, based on mapping of
thermal fronts derived from sea-surface temperature and are furnished to
all the fishing centres of the maritime States in India. This has resulted in
the increased marine fish catch by almost a factor of two to three in
practically all the fishing centres in India.
3.11 Drought Assessment and Monitoring District wise
fortnightly drought assessment bulletins are issued on a regular basis,
for 240 drought-prone districts of the country under the project National
Agricultural Drought Assessment and Monitoring System (N-ADAMS), using
NOAA data. These bulletins have been providing valuable assistance to
district authorities and agricultural resource planners for advance
detection of the extent and severity of agricultural drought conditions,
essential for planning appropriate remedial measures on near real-time
basis.
4.0 Elevation from RS Data Cartographic mapping,
apart from the thematic information, also requires elevation information
which is generally represented as contours on topographic maps. SPOT
satellites with their capability to provide digital stereo data, have
already established the feasibility of obtaining elevation information
for deriving Digital Elevation Models (DEM), which can be used for
generating contours, slopes and other terrain related derivatives. SPOT
data has been used to generate elevation information at 20 m intervals
which is the normal requirement for topographical maps on 1:50,000 scale.
However, factors such as base-to-height ratios of the original
stereoscopic images, image quality, terrain relief, availability of
control points, etc. affect the elevation accuracy of DEMs created from
SPOT. Orthoimages (image equivalents of orthophotos) have also been
generated using geocoded SPOT imagery and DEM models, for extracting
planimetric information, generating map products and merging with GIS
database.
Technological developments taking place for
obtaining high resolution stereo imagery from satellites, are likely to
gradually eliminate the dependency on aerial photography, in the future.
Spatial resolution, often termed as Pixel Size, is the prime factor which
determines the accuracy of mapping from satellite data. Detailed studies
carried out on the relationship between pixel size and elevation
information, have established the relationship:
PS = _1__ * B * 0.3 CI 0.36 H
Where PS is the Pixel Size, B/H is the Base to Height ratio and CI is the
Contour Interval, which is generally a function of the map scale. For
example while map of 1:2,50,000 scale is inadequate to integrate
information on CI at 100 m level, more accurate representation of CI at
20 m or 10 m intervals would require maps of 1:50,000 and 1:25,000
scales. From the above equation, it is clear that to obtain a contour
interval of 10 m on the 1:25,000 scale map, with a B/H ratio of 0.6,
pixel size needs to be about 5.0 m. The relationship between pixel-size
and contour-interval is shown in Table-3.
Table-3
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Scale
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CI(in
m)
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Pixel
Size(in m)
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Possible
error In height (in m)
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250,000
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100
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50
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15
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50,000
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20
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10
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3.33
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25,000
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10
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5
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1.5
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25,000
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5
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2.5
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0.75
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10,000
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2
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1.0
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0.30
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IRS-1C/D satellites, to be launched next year,
having a resolution of about 6 m, will permit generation of contour maps
at 10 m intervals on a scale 1:25,000. Realisation of 1 m pixel size
envisaged for the future satellites, to be launched in the coming years,
will hopefully eliminate the need for aerial photography altogether by
providing contour maps at 2 m intervals.
5.0 Advances in RS Technology The high resolution
second generation Indian Remote Sensing Satellites IRS-1C and 1D having
about 20 m resolution in the multispectral and 6 m in the panchromatic
bands with stereo viewing and more frequent revisit capabilities, have
been specifically designed keeping in mind thematic cartography and DEM
requirements of Indian Cartographers. Along with GPS data, IRS-1C will
facilitate the generation of detailed digital cartographic database with
digital terrain models to help cartographers in evolving appropriate
engineering solutions to complex problems involved in micro-development.
Similar developments are also envisaged in the next generation Landsat-7
and SPOT (3 or 4) satellite systems which will help in the generation of
thematic maps at 1:25,000 scale are better.
US policy to license to private companies to build
and operate remote sensing satellite systems and sell those imageries in
the domestic and foreign markets, have encouraged formation of a few
private remote sensing satellite system ventures such as Eyeglass
International, USA and Worldview International, USA. Likewise smaller
satellite platforms providing 1 m resolution panchromatic data, with only
cartography in view are also being planned by a few countries such as Russia and Israel. Advances in
semi-conductor technology, resulting in the development of 10 to 20 k
linear element CCD arrays have made it possible to obtain 1 m stereo
imaging from space platforms with a revisit capability of 2-3 days.
Before the end of this decade, availability of such value added products
for 3D simulations, DTM's and thematic mapping are expected to become
available enabling cartographers to benefit from these advances, which
can revolutionise the status of cartography on a world wide basis.
Parallel developments in allied fields - Geographic
Information Systems (GIS), Digital Elevation Modelling (DEM) and Global
Positioning Systems (GPS) technologies have resulted in easy integration
of various layers of area specific thematic maps. Use of proper network
of carefully selected Ground Control Points (GCPs) have greatly assisted
in accurate location of various terrain features on the topomaps.
6.0 Evolution of Integrated Cartographic Mapping
Rapid developments in the evolution of appropriate GIS packages have
facilitated the integration and synthesis of different data sets within
the cartographic frame work, making digital maps an important tool in
developmental planning and decision making process. In India,
satellite based remote sensing inputs have become the key to initiate
integrated sustainable development at micro level. The first phase for
this approach consists of preparing a set of resource maps using remote
sensing data on surface water body, ground water potential, wasteland
status, soil maps including erosion status, potential ground water
recharge sites, existing land use including agricultural crop inventory,
Forestry status and meteorological information. Combining these with the
socio-economic factors, integrated land and water resource maps for each
watershed are built up identifying high priority areas for development of
agriculture, fuel and fodder, soil conservation and afforestation, type
and location of recharging strategies depending on the terrain and the
availability of underground water potential. Based on the site specific
surveys using remotely sensed information and conventional data, each
watershed is further sub divided into 400 - 500 microlevel units
depending on soil characteristics for identifying suitable conservation
and management practices and suggesting alternate cropping strategies for
optimal exploitation of soil and water resources. For example, land units
in the drought prone area having a very fertile deep soil, which is well
drained, but constrained by lack of irrigation facilities, have been
recommended for rain-water harvesting and ground water exploration,
whereas those lands having moderate soil depth, gentle slope undergoing
large scale erosion have been suggested for applying soil conservation
measures through contour tillage, strip cropping, etc. Likewise in the
hilly areas where the lands are characterized by moderate to steep
slopes, severe erosion and unsuitable for agriculture, afforestation
along with fuel and fodder plantation has been suggested (Rao, 1993).
With the held of the Planning Commission and active
participation of user departments, 157 districts in the country have been
taken up under the Integrated Mission on Sustainable Development (IMSD)
programme for preparing locale-specific action plans. Actual
implementation of the IMSD in a few selected watersheds like the one at
Anantapur or Akola,
have already provided highly encouraging results. Barren areas where even
drinking water was a scarcity in summer, have now become green with two
crops being grown and the level of water going up by as much as 3 meters.
While historically establishment of ground control
points have been the accepted practice in all photogrammetric surveys,
development of aerial triangulation and sophisticated block adjustment
methods helped in considerably reducing this highly time consuming
requirement. Since the very beginning, it has been the dream of
photogrammetrists to free themselves from the constraints of ground
surveys and devise a system which would permit mapping from aerial
photographs, without the need for costly and time-consuming ground surveys.
The availability of Global Positioning System (GPS), integrated onto
satellite sensors and inertial platforms, capable of providing the
position coordinates with sufficient accuracy has virtually eliminated
the need for ground control surveys in photogrammetric mapping. Use of
differential GPS systems and appropriate statistical methods of analysis
have improved the attainable accuracies of GPS system. GPS based system
is the only practical method available when particularly dealing with
inaccessible, highly heterogeneous areas, where large topographic maps
are not available, and where suitable control features for ground based
navigation by triangulation are difficult to find.
7.0 Conclusions Recent technological innovations in
satellite sensors, evolution of GIS and GPS services and development of a
variety of spatial and temporal query based languages have enabled
generation of better quality maps and digital terrain models with
flexibility of handling, updating and use in various applied studies.
Further efforts are already in progress to generate topomaps in digital
form so as to permit updation through inputs from conventional ground
surveys, aerial photos and satellite stereo coverage. Even though the
potential cost advantages of deriving thematic mapping from satellite
imagery is currently to some extent offset by the low resolution of
satellite sensors, rapid technological advances taking place now hold a
great promise for topographic and thematic map production at a fraction
of the cost involved in conventional mapping. A global database of the
entire planet of 10(4m2 area, even with data field representation of just
16 bits for square meter, would demand 2 x 105 gigabytes needing 4
million tapes or 50,000 optical discs for its storage. Compilation of
such vast data bases, no doubt, require development of faster processors,
high density memory devices, efficient data structures and high speed
communication links. Fortunately advances in semi-conductor and laser
technology has already enabled us to reach femto-second capability. The
advent of digital photogrammetry has already established its superiority
over conventional analog and analytical photogrammetric data processing
instruments, due to its capabilities for online and real time enhancement,
contrast alteration, enlargement/reduction, better accuracy and
interactive manipulation. With this potential, the digital photogrammetry
has become the converging corner where improved satellite sensor
technology and ground systems come together to provide accurate
representation of spatial resource information. The flexibility of
handling, updating and disseminating the necessary information to the
scientist, planner and administrator in a timely manner permitting them
to undertake developmental activities and monitor the consequential
effects has revolutionised cartography on a permanent basis. These
developments have also removed the earlier distinction between map makers
and map users by promoting customised cartography where maps are produced
by the user himself with commercially available simple PC systems.
Developing countries, in particular, with little or
no infrastructural facilities can greatly benefit by directly adopting
the latest techniques to generate maps using high tech space products and
desk top computers. Modern cartography is probably the best example to
illustrate how developing countries such as the African nations can take
a quantum jump in technology, without going through the step by step
process followed elsewhere and thus convert this very disadvantage into a
decisive advantage.
If the initiation of sustainable integrated
management strategies at microlevel is the only solution to provide food
and economic security to the exponentially growing population, it is
equally imperative to have timely methods of constant monitoring and
assessment of the results of the developmental processes initiated, in
order to make appropriate remedial mid course corrections. The world, in
the past, has already been the victim of the negative repercussions of
the very developmental processes such as the classical green revolution
employed for increasing food productivity. Late recognition of the
detrimental ecological effects of human activity has, in most cases, made
the reversal of environmental changes very expensive and time consuming,
if not impossible. The unique characteristics of modern thematic
cartography is the intensive collaboration and integration of a variety
of disciplines working towards a common goal to provide real time
assessment of interplay between a large number of interdisciplinary
activities which cannot always be modeled and predicted because of their
basic non linear nature. Cartography has thus become as essential tool
for the development of the complex society, for the benefit of entire
human kind.
TABLE-2 : MAPPING ACTIVITIES USING REMOTE
SENSING DATA
|
COUNTRIES (Nodal RS
Centre/Agency)
|
Major Mapping Activities using
RS Data
|
Type of Satellite Data used for
Mapping
|
|
ASIAN
COUNTRIES
|
|
Bangladesh Bangladesh
Space Research & Remote Sensing Organisation, (SPARRSO)
|
Flood
Control Crop inventory Coastal mangrove afforestation
|
NOAA/AVHRR
Landsat TM
|
|
China National Centre
for Remote Sensing (NCRS)
|
Soil erosion Forest resources Flood control
Crop yield Geology & Non-renewable resources exploration Urban
environment Environment Impact assessment
|
NOAA/AVHRR
Landsat TM, SPOT, SLAR, SAR
|
|
India Indian Space
Research Organisation (ISRO) & National Remote Sensing Agency
(NRSA)
|
Agriculture
*Crop Inventory *Shifting cultivation Forest Monitoring Wasteland
monitoring Environmental Monitoring *Urban sprawl *Land degradation
Drought monitoring Ground water targeting Surface water inventory Snow
area mapping Flood affected area mapping Soil categorisation Landuse
mapping Geological mapping Coastal monitoring
|
IRS
Landsat TM SPOT, ERS-SAR NOAA/AVHRR
|
|
Indonesia
Indonesian National Aeronautics & Space Institute, LAPAN
|
Forest resources Urban
Planning & Development Crop inventory Geology & Mineral
exploration Coastal zone & marine resources Global &
environmental change
|
NOAA/AVHRR
Landsat MSS
|
|
Countries
(Nodal RS Centre/Agency)
|
Major
Mapping Activities Using RS Data
|
Type
of Satellite Data Used for Mapping
|
|
Malaysia Malaysian Centre
for Remote Sensing
|
Land
use Soil erosion/watershed Coastal changes Geology & mineral
exploration Ground water exploration
Forest resources
Agroclimatic Impact studies
|
NOAA/AVHRR
Landsat MSS SPOT-1 SLAR
|
|
Mongolia
|
Snow
cover studies Environmental & disaster monitoring Water & land
management Forest fire alarm Crop
yield estimation
|
Landsat
MSS Landsat TM COSMOS (USSR)
Meteor (USSR)
NOAA, GMS
|
|
Nepal Nepal
Remote Sensing Centre
|
Forest
Soil conservation/watershed
|
Landsat
MSS Landsat TM
|
|
Pakistan Space & Upper
Atmosphere Commission (SUPARCO)
|
Agriculture
Forestry Water resources Geology/geomorphology Environmental &
landuse
|
Landsat
MSS Landsat TM SPOT NOAA AVHRR
|
|
Philippines National Mapping
& Resource Information Authority
|
Forest
Landuse/agriculture Coastal zone management Geology Information
management
|
Landsat
MSS Landsat TM SPOT NOAA AVHRR
|
|
Sri
Lanka Centre for Remote Sensing
|
Forest
Tea acreage & condition Land use
|
Landsat
TM SPOT
|
|
Thailand Thailand
Remote Sensing Centre
|
Forest & environment
Coastal zone Watershed Landuse/land cover Disaster assessment
|
Landsat
MSS Landsat TM SPOT MOS-1
|
|
Vietnam National Centre
for Scientific Research, NCSR
|
Coastal
studies Flood Forestry Ground water Landuse/land cover Crop inventory
|
GMS
NOAA AVHRR Landsat
|
|
SOUTH AMERICA (Society for Latin
American specialists on Remote Sensing, SELPER) Brazil Institute of
Space Research (INDE)
|
Mineral &
Geology Forest Crop inventory
Ocean & Environmental studies
|
Landsat
TM SPOT
|
|
Argentina Argentina's
National Commission for Space Research (CNIE)
|
Crop
evaluation Geological & mining surveys Flood studies Forest evaluation Water resources & pollution
|
Landsat,
MSS Landsat TM NOAA/AVHRR
|
|
Egypt Remote Sensing
Centre, RSC
|
Drainage
Geology, mines, petroleum & minerals, soil, vegetation & land
use Ground water potential Town planning & coastal studies
|
Landsat
MSS Landsat TM NOAA/AVHRR SPOT
|
|
Kenya (ARSC)
|
Crop
monitoring Soil surveying Habitat mapping Forest,
geological Disease & pest application Coastal studies
|
Landsat
TM Landsat MSS
|
|
Nigeria (ARSC)
|
Forest & wildlife
Vegetation & landuse Geomorphology etc.
|
Landsat
MSS Landsat TM SLAR
|
|
Nigeria (ARSC) Countries
(Nodal RS Centre/Agency)
|
Forest & wildlife
Vegetation & landuse Geomorphology etc.
|
Major
Mapping Activities using RS Data Landsat MSS Landsat TM SLAR
|
|
Type
of Satellite Data used for Mapping
|
|
Australia Australian Liaison
Committee on Remote Sensing by Satellite, ALCORS
|
Mineral
exploration Crop inventory Pasture condition & assessment
Vegetation classification Forestry & rangeland monitoring
|
Landsat
TM Landsat MSS SPOT, NOAA/AVHRR ERS, MOS, JERS
|
|
|
