Image Processing Reference
In-Depth Information
Chapter Summary
As the earth's population increases, cities will continue to grow and spread.
However, this continual growth comes with a range of environmental draw-
backs which are typically magnified in developing countries. Examples of
these drawbacks include rapid and haphazard urban sprawl and increasing
population pressure in megacities often infringes upon agricultural and/or for-
est land. Analyzing agricultural and urban land use is important for ensuring
that development does not encroach on productive agricultural land, and to
likewise ensure that agriculture is occurring on the most appropriate land and
will not degrade due to improper adjacent development or infrastructure.
The multi-temporal multi-spectral analysis of satellite remote sensing data
facilitates the process of monitoring land use in both agricultural and urban
settings but the application varies between developed and developing coun-
tries. In alignment with other chapters in the topic discussing the context of
developing countries, this chapter discussed the impact of rapid urban growth
on land use changes, especially on the agricultural land in Turkey and the
way in which remote sensing is used to assess and monitor these changes
using a case study from Büyükçekmece in Istanbul. Büyükçekmece has been
experiencing expansion of informal settlements and continuous population
growth (40% in some regions) due to (i) intensive migration from the other
parts of Turkey, (ii) the building of new transport networks such as Trans-
European Motorway (TEM) which crosses Büyükçekmece, and (iii) natural
population growth and rapid urbanization over a period of 15 years.
The chapter showed how land use changes associated with this growth
could be detected using simple change analysis techniques such as image dif
ferencing and vegetation indices. Comparing with many analytical tech-
niques introduced in earlier chapters in the topic, the techniques introduced
in this chapter are considered much less sophisticated. Nevertheless, and as
previously discussed in Chapter 13, the results of the analysis showed how it
is possible with relatively simple techniques to utilize urban remote sensing
in generating reliable measures and new layers of information that otherwise
not readily available in developing countries.
LEARNING ACTIVITIES
Study Questions
•
The case study discussed in this chapter utilized NDVI - a ratio-based vegetation
index - to understand change in agriculture lands between 1998 and 2002 in a
sub district within Istanbul.
