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GIS
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Assessment of Map Cetainty on Urban Growth using Remote Sensing and GIS Integration
3. The Application
The application investigates the certainty of some local maps currently used in planning
and management of Ha Noi. These local maps published in the early 1990s include the
topographic maps of HSMC (1989) and of DMCD (1994) and the report by VUTAP (1995).
The study area is the Lang Ha and Thanh Cong wards in the rapid urbanized fringe of Ha Noi
City where the comparative RS products are available from Swedish Space Cooperation (SSC)
project in Ha Noi. This product provided up-to-date information on changes of water surfaced
areas during the 1979-1989 period (Paulsson et al., 1995). The question is if the local maps also
describe such land use changes. The application only assesses the elevation element in the local
maps. The tools used include Arc/Info for map transform and overlay, Excel and Surf for geo-statistic
analysis and Mapinfo for display.
For integration, the selected maps are registered and transformed into the base system of
the DMCD map. The VUTAP and SSC data are input (digitized and scanned) and interactively
registered to the DMCD control points. The variation analysis uses map overlay. Figure 2 shows
the elevation variation between the value of each DMCD elevation point and the averaged value
of the HSMC elevation points, which fall within the 50m-radius buffer around such DMCD
points.
Figure 2: Comparison of Elevation Data between DMCD Map and HSMC Map
Source: DMCD, 1994; HSMC, 1989
These elevation variation is then interpolated into contour model demonstrating the
increase trend of DMCD elevation values compared to those of the HSMC map as well as the
data distortion due to the lack of DMCD data over water area. The composite map overlay on
Figure 3 shows a considerable convergence of the selected data on the urban growth in the area.
The elevation increase relatively match with the decreased water areas identified by the SSC
data. Generally, the elevation contents in the local maps are reliable in describing the land
leveling phenomena and its occurred area. Some uncertainties due to the time scale between RS
data and the local maps, the lack of DMCD elevation value on water surface, the elevation
modeling at 1:10,000 and 1:2,000 scale (point number and location), the rapid urban change
when the maps were being produced, should be further investigated.
Figure 3: The Decreased Water Area and Elevation Increase in Lang Ha Thanh Cong
4. Conclusion
The urban growth in developing countries like in Viet Nam is rapidly happening but the
local maps are often uncertain for planner to plan for the process. The paper discusses the
integration method using RS product and GIS tools for rapid assessment of the local maps. The
application shows the ascertained map contents that could be used for further studying the urban
growth pattern, the impact of water bodies reduction on open space and drainage, and the map
inconsistencies for future improvement. The integration method demonstrates relative
advantages by its low cost and flexible use of different data and tools. We believe that it will be
useful and applicable by the local planner in assembling, verifying data certainty and successive
data utilization in the planning process.
Reference from Journals:
- Stein, W.G.M. Bastiaanssen, S. De Bruin, A.P. Cracknell, P.J. Curran, A.G. Fabbri, B.G.H.
Gorte, J.W. van Groenigen, F.D. van De Meer, and A.Saldana, 1998. Integrating spatial
statistics and remote sensing. International Journal of Remote Sensing, Vol. 19, No. 9,
1998, pp. 1793-1814.
Reference from Books:
- NIURP, 1992. Ha Noi Population Databook. National Institute for Urban and Rural Planning
and United Nation Fund for Population Assistance (UNFPA), Ha Noi.
- HSO, 1998. 1998 Statistical Yearbook. Ha Noi Statistical Office.
- VUTAP, 1995. The Phuong of Ha Noi. First edition, The Viet Nam Urban Transport Assistance
Project, Ha Noi.
Reference from Other Literature:
- Aggarwala, Rajendra K., John D. Nystuen, Andrea I. Frank, and Jyothi Palathinkara, 1997.
Using GIS to Evaluate the Quality of Digital Map Databases of Road Networks.
Proceeding paper at Conference on Computer for Urban Planning and Urban
Management CUPUM 1997 Bombay India pp. 493-502.
- DMCD, 1994. Ha Noi City 1:10,000 Scale Map. The Defense Ministry Cartographic
Department, Ha Noi.
- HSMC, 1989. Dong Da District 1:2,000 Scale Map. The Ha Noi Survey and Mapping Company,
Ha Noi.
- Nghi, Duong Quoc, 1999. Integrating Land-Related Information for Urban Planning and
Management in Ha Noi City, Viet Nam, doctorate thesis progress report, Space
Technology Research and Applications Program, Asian Institute of Technology,
Bangkok, Thailand.
- Paulson B. and Ahcrona E., 1995. Monitoring Urban Growth in Developing Countries Through
Satellite Remote Sensing. Final report, Swedish Space Corporation, Solna, Sweden.
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