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INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES
Volume 3, No 3, 2013
© Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0
Research article ISSN 0976 – 4380
Submitted on January 2013 published on March 2013 552
Land use and cover change assessment using Remote Sensing and GIS:
Dohuk City, Kurdistan, Iraq (1998-2011) Jambally Mohammed
School of Planning, University of Duhok, Dohuk, Kurdistan region of Iraq
ABSTRACT
Land cover undergoes continuous changes around the world, especially in highly populated
areas. This phenomenon can be attributed to human activities including population growth
and the need of more housing. Dohuk, like many other cities in Iraq, has undergone a rapid
urban growth mainly due to the population growth after 2003. With the absence of efficient
urban planning systems and regulations in the past, this city has witnessed uncontrollable
urban growth with adverse environmental impact. This growth has encroached upon
peripheral agricultural lands, caused considerable lack of open spaces, and resulted in a
degraded urban environment, e.g. higher proportion of concrete and asphalt surfaces and
increased temperature in summer. This paper follows an integrated approach of using remote
sensing and geographic information system (GIS) to measure and analyze the urban growth
in Dohuk city over three periods of time (1998, 2007, 2011). Its main goals are to
demonstrate the effective use of such modern techniques in mapping, identifying, and
assessing land use/land cover (LULC) changes and urban growth trend and in addressing the
current lack of urban growth information by providing relatively accurate data to help the
planners in identifying the driving forces behind current LULC changes and in managing the
urban growth in a more systematic manner. Spatial patterns of LULC change were identified
through LULC classification and change detection analyses conducted on multi-temporal
Landsat Thematic Mapper (TM) data. Three Landsat satellite images for the study area for
1998, 2007 and 2011 were processed and classified into three LULC categories: Vegetation,
Barren Land, and Urban/Built-up Land. The results show a remarkable increase in the
urban/built-up area with corresponding decreases in the barren land and vegetation areas
during 1998 and 2011. The paper also demonstrates that the city is growing rapidly which
could assimilate more agricultural and rural areas.
Keywords: Land Use/Cover, GIS, Remote Sensing, Urban Growth, Landsat imagery, Dohuk.
1. Introduction
Urbanization is a significant global phenomenon and it becomes a great concern for many
parts of the world. Thompson Warren defines this concept as the "movement of people from
agricultural-based communities to other larger communities that primarily depend on
government, trade, manufacture" or personal interests as main activities (Sociology Guide,
2012). Urbanization is an inevitable process in the areas that experience rapid economic
developments and population growths. Urban growth accelerates movement of residential
and commercial land uses to rural areas, thus creating noticeable effects on land use through
sprawl (Rimal, 2011). It has an adverse impact on the urban map, especially when it involves
movement of large populations from rural to urban areas which creates a subsequent increase
in the urban population and conversion of other types of land to uses associated with the
growth of populations and economy (Sociology Guide, 2012). Urban growth and urban
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 553
development or urbanization are two major factors that influence land uses and plague most
urban areas throughout the world. They bring unrestrained impact on land use/land cover
(LULC) change and patterns, and create critical imbalances among patterns. LULC changes
have become the main challenge of the present world, and they create severe threats for major
cities of the world (Rimal, 2011). Masser (2011) noted that monitoring and evaluating urban
change is a major issue in urban planning and management throughout the third world.
An unplanned urbanization process is now a major problem, especially in the developing
countries where there is lack of consistent and reliable data including spatial data. Such
situation is highly evident in Iraq where conflicts, political and factional instability, and
subsequent internal displacements and migration; population growth; and improved economic
opportunities are the driving forces behind the high level of urban growth, particularly in the
big cities of the northern Kurdistan Region that enjoys a complete state of security and
economic stability. Reference (Guttenberg, 1959) indicated that land use is a key term in the
language of city planning. A success of urban planning requires a proper regulation of land
uses in order to avoid uncontrollable urban growth or sprawl. It is also known that land use
plans are implemented through land use ordinances and regulations, such as zonings, and that
the urban growth boundary is one form of land-use regulation for controlling sprawl and
random movements from urban centers towards agricultural countryside. However, such
means were not effective in Dohuk or are still not strongly enforced there. This could also be
attributed to the absence of an efficient system for acquiring data about the local urban
movements and patterns.
In view of these facts, there should be a wise and rational use of lands in order to make a
balance between the life necessities that use lands as a source. While urban areas are usually
dominated by human influence and the associated land use patterns, an efficient method
should be used to deal with land use change processes. Such method certainly formulates the
basis of any sound urban planning and should be built upon reliable data. Policy makers and
planners need to make use of all available tools and data to detect LULC changes and urban
growth trends to make sound and precautious urban plans and sprawl control/mitigation
systems. Reliable and accurate data are required for development of urban plans; however,
such data cannot be easily obtained without using an efficient technology such as satellite
imagery. Remote sensing, which is the extraction of information about an object on the earth
without making physical contact with it (Robert, 2007; John, 2007), is considered as a
powerful tool in the change detection of the land surface; therefore, urban growth is highly
involved in remote sensing and GIS applications (Al Fugara, B. Pradhan and T. Mohamed,
2009; Geymen and Baz, 2008; Treitz and Rogan, 2003). Masser (2011) also demonstrated
that GIS is an appropriate tool for applications in the field of urban planning and management
because it integrates information from different sources. Remote sensing and GIS have been
proved to be effective and accessible means for extracting and processing spatial information
obtained from satellite and aerial images for monitoring urban growth. The correlation
between population growth and urban growth can be determined from the Landsat-derived
change maps (Masser, 2011).
This study intends to determine the extent of LULC change in Dohuk city throughout the
period under study (1998-2011), to highlight the driving forces behind these changes, and to
suggest appropriate recommendations to address the current rapid urban growth. While
accurate and LULC information/databases are not available for the study area, this paper uses
the powerful technology of remote sensing and GIS to process three Landsat satellite
imageries for the detection, measurement, and analysis of LULC changes in this part of Iraq.
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 554
2. Study area
The study focuses on Dohuk, a city located between latitudes (N 36º48’32’ and N 36º53’15’)
and longitudes (E 42º55’29’ and 43º0’34’), as shown in figure 1. Dohuk is situated in the far
northwest of Iraq, about 470 km north of Baghdad, the capital of Iraq. This city is the center
of Dohuk province, one of the three provinces of Iraqi Kurdistan Regional Government
(KRG), and the center of Dohuk district, one of the six districts of Dohuk province. Dohuk is
a city of interest, notably because of its historical and geographical characteristics. It has a
strategic location since the international strategic transport road that connects Iraq to Turkey
and Syria passes through its territory. Dohuk is situated in a wide valley extended between
two opposing mountain ranges, namely Bekher Mountain in the north and Zawa Mountain in
the south, as shown in figure 2. From the east, it is bordered by Etit village at the foothill of
Mamseen Mountain. From the west, it is opened to Semel agricultural plain. Therefore, it
takes the shape of an irregular long triangular strip and it is elongated from east to north-west.
Two small streams flow through Dohuk with decreased water level in summer. Both rivers
meet in the south-west of the city to form Dohuk River that flows into Mosul Lake, about 22
km south west of Dohuk. The water of these streams is used for irrigating the fruit farms that
historically spread on their banks. Dohuk Dam was built over Dohuk valley catchment to the
Figure 1: Location of the study area
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 555
north of the city during 1980-1988 for irrigating vast rain-fed agricultural lands, which are
located to the west of the city center and extend up to neighboring Semel district (Chatty,
2010; Brendan, M. John and S. Khaled, 2005; Wikipedia). However, this dam has not been
used for the intended irrigation purposes and the targeted agricultural lands have been
gradually converted into urban uses. The dam does not fall within the study area
Dohuk has undergone a fundamental change in LULC patterns due to accelerated economic
development since 2003. Urban growth has been speeded up and considerable agricultural
lands have disappeared. This urban march has greatly accelerated especially because of lack
of appropriate land use planning including a balance between urban/built-up and other land
uses especially green cover. As a result, Dohuk has been growing at unprecedented rates,
creating extensive urban landscapes and facing growing problems of urban growth and loss
of open spaces and vegetation. This city has expanded remarkably over the last 35 years.
Landlocked by mountains on three sides, Dohuk has grown as a 2 x 2 km small compact town
with an agricultural rural-characteristic community of an estimated population of 70,000 in
1977 to an approximately 15 x 3 km city of over 400,000 persons now. The greatest urban
development took place during 1973-1984, 1986-1994, and 2006-2011. The initial settlement
was historically established in a central location in the valley between the two mountains,
shown in figure 3. It was initially inhabited by a limited number of families who occupied
certain close-knit neighborhoods. This location was surrounded by eleven villages with a
radius distance of about four km. Since 1970s, the compact city center started to expand
taking a radial shape and encroaching upon the agricultural lands primarily in the western and
eastern parts inside the valley. Over time, more residential neighborhoods were established
around the city center, and the expansion moved further during 1980s to annex the southern
parts to reach the foothills of Zawa Mountain. The expansion had doubled towards the
Figure 2: Aerial image of the study area, 2010
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 556
western open spaces in late 1990s, registering slower population densities. After 2000, the
city began to expand further toward the western plains, eastern countryside, and marginal
lands at the foothills of the two mountains, as shown in figure 4. (Dohuk Urban Planning
Directorate, 2007). Due to insufficient land allocation and policies to cope with the
challenges of shelter delivery and poor living conditions of the people, informal settlements
and slums, characterized by weak housing structures and poor services, have plagued the city
at the periphery. Still some new areas had been developed as informal settlements that were
originally villages located within Dohuk periphery and later annexed to the city urban extent.
The population density in Dohuk ranged from less than 50 persons per hectare to more than
250 persons per one hectare, based on the residential areas in 2007. For example, in older
neighborhoods, which were established around the city center prior to 1990s, the population
density reached over 250 persons per hectare (Dohuk Urban Planning Directorate, 2007).
With the improved living conditions, increased marriages, and subsequent need of new
families to separate from nuclear families, the need arouse for more housing. With the
economic boom witnessed by the region after 2003, there has been an increased reduction in
the amount of lands allocated for open spaces or conservation, and there has been a
remarkable encroachment of urban development upon these zones. According to Master Plan
Dohuk City 2007, about 68% of Dohuk area was residential in 2006 and that this city has
preempted eight out of eleven villages on its periphery to annex them as urban quarters (see
Figure 3: Views of Dohuk city in 1950s and in 2007
Figure 4: Development Phases of the study area (Source: Master Plan Dohuk City, 2007)
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 557
figure 5). Because of the high value of land and inability of most inhabitants to acquire larger
parcels of lands, the prevalent housing types in Dohuk is attached, single-family, 1-2 story
houses (usually 200 sq. meter). The houses are often are placed wall-to-wall and back-to-
back with relatively no open spaces in between. As a result, the compact horizontal expansion
has been the common housing mode.
3. Methods and materials
3.1. Data preparation
The study area is limited to the current administrative border of Dohuk city which was
digitized and processed by the author using ArcMap 9.3.1, the latest version of Google Earth
image as well as the handy functions of Erdas Imagine 9.2. Meanwhile, a combination of
softwares (Elshayal Smart Web on Line Software, Global Mapper, and Ozi Explorer) was
used to download (from Google Earth), rectify, and project two satellite images for the city
for October 2004 and May 2010 for use in processing the Landsat images. The study is based
on three 7-band TM images (with a resolution of 30 x 30 m pixel) acquired for the study area
(on 13 June 1998, 14 June 2007, and 3 July 2011) from Landsat 4 and Landsat 5. These
images were obtained with path/row 17/34 from the U.S. Geological Survey website. Using
Erdas Imagine, five bands (1, 2, 3, 4 and 5) of each image were stacked, rectified to Universal
Transverse Mercator coordination system (WGS 1984, zone 38N), and masked to the
boundary file to subset the study area. The processed images are presented in figure 6.
3.2. Image classification
Multispectral image classification is used in remote sensing to categorize all pixels in an
image to produce thematic maps of the existing land cover (Levin, 1999). Spectral
information represented by the digital numbers in one or more spectral bands is used to
classify each individual pixel. Two types of classification (supervised and unsupervised) are
used for processing satellite images. Each of these methods groups the pixels of an image into
homogeneous classes in order to portray the spatial distribution of different features detected
Figure 5: Peripheral villages around historical Dohuk city center
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 558
Figure 6: Masked Landsat images of the study area
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 559
by the satellite sensor. The choice of the methodology depends on the strategy of sampling
pixels and the analyst’s knowledge of the study area (Favretto, 2006). The supervised
classification depends on the experience and accuracy of the user and his optical capability in
detecting the signature differences between various patterns in the satellite image while the
unsupervised classification doesn’t require a direction from the user and it depends on the
computer to separates the pixels into classes (Sabins, 1997). Since the supervised
classification does not efficiently differentiate between various LULC patterns, the
unsupervised classification was used in this study to provide more accurate results. The three
masked TM images were classified into 50 classes, which were later recoded into three major
categories: Vegetation, Barren Land, and Urban/built-up Land, following the land cover
classification scheme defined by Anderson et al (Anderson, Hardy, Roach and Witmer, 1976).
Shapefiles of major roads and streets within the study area in 1998, 2007, and 2011 were
digitized, processed, and superimposed (forced) on the respective classified imagery to
produce the final LULC map. The author's familiarization with the study area, availability of
Google Earth's imagery for 2004 and 2010, and ground control points have helped in proper
identification of the LULC classes. A set of rules was set to ensure a proper classification
process. For example, the land used as a parking lot or a dirt road was classified under
Urban/Built-up, an agricultural field cultivated to cereal crops or a natural pasture land was
classified under Barren Land, and a park with green turf or a regularly vegetated grapevine or
almond farm was classified under Vegetation. The classified images are presented in figure 7.
3.3. Accuracy assessment
Accuracy assessment is a valuable tool and a critical step for determining the quality of the
information derived from remotely sensed data. This process defines the degree of coherence
of the classified image with the ground truth (Congalton, & Green, 1999; & Martellozzo &
Clarke, 2011). The accuracy of an image classification depends on the number of samples
taken for each class and the quality of reference images used for analysis. The accuracy
assessment usually evaluates the effectiveness of classifiers (Ngigi et al., 2008) with the help
of field data by testing the statistical significance of a difference through computation of
kappa coefficients (Congalton, Oderwald & Mead, 1983) and the overall accuracies. A
considerable number of (reference) pixels are taken from the classified image and compared
with a reference map of higher authority to evaluate correctness of the classification process
(Jensen, 1996). This comparison is built on an error matrix (overall accuracy) and use of a
sampling strategy for selection of pixels. The Kappa coefficient ranges from 0 to 1; values
higher than 0.7 are considered acceptable, while those equal to or lower than 0.4 identify a
very low correlation between the classified image and the ground truth (Jensen, 1996).
Table 1: LULC classification scheme for the study area
LULC Type Description
Vegetation
Irrigated fruit orchards, rain-fed forest trees (deciduous and evergreen), irrigated
and rain-fed grapevines, rain-fed almond farms, plant nurseries, parks, gardens,
and playgrounds with green turf.
Barren Land
Seasonal croplands (wheat, barley, etc.), sparsely vegetated rain-fed pastures and
grasslands, mountainous and rocky areas, and other lands that are not disturbed by
urban development or encroachment.
Urban/
Built- up
Land
Residential, commercial, services, utilities, public and private infrastructure;
buildings, roads, concrete and asphalt surfaces, built-up and other lands disturbed
by development or human intervention.
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 560
Figure 7: Classified Landsat images of the study area
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 561
The accuracy for each of the three classified images was assessed taking as a reference
available images and maps of respective time period. This process was supplemented with
previous knowledge and ground checks. Accuracy assessment was performed for a total of 50
pixels on each classified image, using random sampling strategy for selection of the pixels. In
addition, a set of ground control points (150) was collected from well-known locations and
landmarks such as old public buildings and hills in the study area with a hand-held GPS
receiver in the summer of 2012. Of these field data, 60% were used for classification, while
the balance was used for the accuracy assessment. This information was supplemented with
Google Earth and the author’s previous and current knowledge of the object scene of the
study area.
Table 2: Summary of error matrixes for the classified images for the study area
Reference Map Image Overall
Accuracy
Kappa
Index
Topographic map 1998 + Google Earth image
2004 + ground control points Landsat 1998 85.33% 0.7473
TerraServer image 2007 + ground control points Landsat 2007 86.00% 0.7834
Google Earth image 2010 + ground control points
(ground checks) Landsat 2011 90.00% 0.8438
The results indicate that the overall accuracy for the three classified Landsat images is above
the minimum acceptable level of accuracy (85%) to be used for efficient LUCC analysis and
modeling (Pontius, 2003). This is the accuracy value for reliable land-cover classification set
by Anderson et al. (Anderson, Hardy, Roach and Witmer, 1976). The Kappa coefficient, a
measure of agreement, can also be used to assess the classification accuracy (Congalton,
1991). This coefficient often appears to be low (Muzein, 2006) as it considers both the actual
agreement in the error matrix and the chance agreement (Congalton, 1991). Kappa coefficient
calculated for the three images for 1998, 2007 and 2011 are 0.74, 0.78 and 0.84, respectively;
these are acceptable values since they are above the threshold of 0.7 (Jensen, 1996).
3.4. Image analysis
Remote sensing techniques have been proved as a valuable tool in mapping urban areas and
becoming data sources for the analysis and modeling of urban growth and land use change
(Batty and Howes, 2001). Remote sensing provides spatially consistent data sets with large
geographical coverage, high spatial detail, and high temporal frequency (Martin, 2003). It can
also provide consistent historical time series data (Batty and Howes, 2001). There are many
techniques that can be used for urban LULC mapping for change detection from satellite data
(Masek, et al., 2000). However, selection of a good change detection method could be
sometimes difficult (Lu and Weng, 2004). Therefore, effective image classification for urban
LULC mapping and change detection depends on many factors, with main consideration
given to the selection of available multi temporal data, processing and method of image
classification.
In this study, LULC change detection and analysis are based on a series of afore-mentioned
data and image processing operations. Spatio-temporal LULC detection and analysis were
carried out using unsupervised pattern classifier. Unsupervised classification with 50 sample
points was run on a composite of five bands (1, 2, 3, 4 and 5) for each of the three Landsat
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 562
images. The produced LULC thematic layers were used as a basis for the detection and
analysis of urban change in the study area by grouping the spatial features associated with the
LULC into three major categories: Vegetation, Barren Land, and Urban/Built-up Land, as
illustrated in figure 7 and table 3. LULC change results are also obtained by comparing the
reclassified raster images of two time periods (Anurag, 2012). For this end, ESRI ArcGIS
with its Spatial Analyst Extension was used for proofing the LULC detection and analysis
done in Erdas Imagine. Overlay analysis was done using the raster calculator tool in ArcGIS.
The classified raster maps of LULC data for the three respective years were subtracted from
each other to find areas of LULC change over two time spans (1998-2007 and 2007-2011), in
addition to an overall span (1998-2011), as presented in Figure 8. For example, the
reclassified raster image of 2007 was subtracted from the respective image of 1998 to find
out the changes in LULC (the three categories) during 1998-2007. To isolate areas of change,
the produced image was reclassified, maintaining the cells in the areas with changes. The
same procedure was applied to the two reclassified images of 2007 and 2011, and also of
1998 and 2011 to detect the LULC changes during 2007-2011 and 1998-2011, respectively.
The three final images present an overall picture of the degree and directions of changes in
LULC in the study area. On the basis of these images, the change in the urban/built-up land
cover was detected and mapped for the three periods of 1998, 1998-2007, and 2007-2011.
Figure 9 shows three new reclassified rasters over the respective periods as superimposed on
each other to produce a final map that outlines changes in the urban/built-up land cover
during the afore-mentioned three periods.
4. Results and discussion
4.1. Change detection analysis
An estimation of the area of each classified LULC type or surface was made on the basis of
the number of existing pixels. The three LULC types were computed by multiplying the pixel
dimensions (30m x 30m) by the total number of pixels on respective surfaces. As shown from
Table 3 and Figure 10, a remarkable increase was registered for the urban/built-up land in
parallel to decreases in the barren land and vegetation during 1998-2007 and 2007-2011. The
area of urban/built-up land registered a continuous, but irregular, increase of 191% during
1998-2007 and 40% during 2007-2011. Oppositely, the area of barren land decreased on a
steady basis by -11% during 1998-2007 to -22% during 2007-2011. As for the area of
vegetation, there was a decrease of -50% during 1998-2007 but it was reversed to an increase
of 26% during 2007-2011.
Table 3: Area classified for each land cover type for the study area
Class
Area
1998 2007 2011
Acre Sq.
Km % Acre
Sq.
Km % Acre
Sq.
Km %
Vegetation 4,795 19 20.65 2,393 10 10.30 3,025 12 13.03
Barren Land 16,260 66 70.01 14,523 59 62.53 11,374 46 48.98
Urban/built-
up Land 2,169 9 9.34 6,308 26 27.16 8,825 36 38.00
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 563
Figure 8: LULC change in the study area
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 564
The total percentages of changes, presented in table 4, in the urban/built-up land, barren land,
and vegetation during 1998-2011 are 231%, -32%, and -24%, respectively. The increase in
the urban/built-up area is attributed to the population growth and immigration of large
populations from the rural areas and other parts of Iraq with deteriorated security sit uation to
the study area, improved living conditions of the local people and the subsequent increased
demand on housing, and extensive horizontal expansion of the study area. Such urban
expansion was made at the expense of barren land and vegetation. It is to be noted that the
increase in the vegetation cover gained during 2007-2011 was attributed to more attention
paid by the government to improving the green cover by rehabilitating/establishing parks and
gardens, planting more trees, and encouraging vertical expansion through construction of
apartment complexes with acceptable proportions of green cover (trees, parks, green turf).
In general, the biggest increase in the urban/built-up land is observed in the western area, a
solid indicator that the rapid urban growth of this city will continue in that direction to
assimilate more agricultural lands and annex neighboring Semel town. This is evident, as
shown in figure 9, from the existing topography – enclosure by mountains form the north and
the south – that pushes the urban growth more in the western direction.
Table 4: Observed growth in LULC types (in km2)
LULC Class 1998-2007 2007-2011 Total
Vegetation -50% 26% -24%
Barren Land -11% -22% -32%
Urban/Built-up Land 191% 40% 231%
4.2. Driving forces
There are several factors that have directly and indirectly caused considerable changes to
Dohuk LULC. Population growth is a major one. The total population of this city has steadily
increased by 54% during 1998-2007 and by 14% during 2007-2011, with an annual growth
Figure 9: Urban/Built-up extent of the study area
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 565
rate of 6.8% in early 2000s. This increase can be attributed to the promoted birth growth as
the inhabitants are mostly governed by inherited social traditions that encourage early age
marriages and having more children. This accounts for the average family size to reach 6.7
persons in 2000s. This tradition, combined by improved living conditions of the residents and
a stabilized region, has led many individuals to get married at early ages (Dohuk Urban
Planning Directorate, 2007; UNDP, 2004). During fourteen years (from 1998 to 2011),
Dohuk urban population grew by 76%, about three times less than rate (231%) of urban/built-
up growth. This means that land was being inefficiently used.
Table 5: Urban growth vs. population growth in the study area
1998-2007 2007-2011 Total
Urban/built-up growth 191% 40% 231%
Population growth 54% 14% 68%
Immigration for employment and better living opportunities is another fact that has
contributed to the increased urban growth in Dohuk. Since mid 2000s, large numbers of the
rural population immigrated to Dohuk, seeking better employment opportunities and access
to services. This can justify the fact that the population of this city represented about 30% of
the overall population of Dohuk province in 2006 (Dohuk Urban Planning Directorate, 2007;
Swiss Refugee Council, 2007). Compulsory displacement of people functions similarly.
Dohuk has received an influx of people displaced from the central and southern troubled Iraqi
areas, especially Baghdad where there have been widespread violence and collapse of law
and order after 2005. Dohuk, like other KRG areas, has enjoyed since 2003, a safe and stable
situation and prosperous business opportunities that have attracted such great numbers of
internally displaced people (IDPs). For example, there were 11,482 IPDs in Dohuk city in
2007 (UNHCR, 2007).
Improved economy, living conditions, and purchasing power of the inhabitants have also
contributed to the rapid growth of the study area. Since 2003, Kurdistan region including
Dohuk has experienced an economic boom because of a combination of factors including the
Figure 10: Trend of LULC change in the study area, 1998-2011
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 566
established government and public administration, staple political and security situation, and
favorable business environment. This boom is largely attributed to the increased financial
resources provided for KRG provinces. Unlike the previous period (before 2003) when
Dohuk province mainly depended on tax revenues generated from the imports and
international trade with Turkey, now Dohuk receives a stable share of funds from KRG
budget, which is about 17% of the total annual Iraqi oil-based budget (USAID, 2008). As a
result, the number of public employees with good earnings has increased remarkably in
Dohuk. This factor together with the free distribution of housing land plots to the employees
has enabled many of them to have access to new houses.
5. Conclusions and recommendations
The present study has detected and assessed the trend of urban LULC in Dohuk city, using an
integrated approach that included GIS and remote sensing tools as well as statistical
calculations. It has demonstrated an effective utilization of this approach in detecting LULC
change and assessing extent of urban growth without depending on costive and inefficient
land surveys. It has shown a considerable increase in the urban/built-up area during 1998-
2011. It has presented a clear picture of a potential occurrence of sprawl toward the western
plain in view of the current urban growth trend. This growth is expected to increase with
more encroachment upon agricultural lands and open spaces, if a wise urban planning
approach is not developed and enforced. Meanwhile, the study has addressed the gap in the
lack of information about the existing LULC types which can assist the planning authorities
in formulating a solid planning system for the growth of the study area. The output of this
research can be used as a model to trigger similar initiatives at official levels, namely by the
planning authorities, in an effort to detect and measure LULC change, and address current
urban problems.
In view of the study results, a set of recommendations are presented here for creating a
balance between the urban/built-up and green cover in Dohuk and ameliorating its urban
environment and climate. A holistic approach needs to be adopted for increasing the green
cover in the city at the expense of cement and asphalt surfaces. This can be achieved through
various means such as plantation of more trees, especially on sidewalks in the residential
areas and on public/private properties. This also requires community awareness in the
adverse impact of current inefficient urban form and the importance of establishing an
environment friendly city. Meanwhile, a study needs to be conducted on the possibility of
reforesting the barren slopes and foothills of Bekher and Zawa mountains. Accordingly, an
action plan can be developed to bring back the green cover to at least some portions of the
two mountains on an efficient and sustainable manner. A more rational and favorable vertical
housing approach with international standards should be enforced and encouraged to
minimize the horizontal compact development. In addition, affordable green, environment-
friendly housing projects should be encouraged. Most importantly, the planning and decision-
making authorities must integrate new technologies, such as remote sensing and GIS into
their decision making process. Using remote sensing data and information to understand the
dynamics of the urban environment may contribute to better urban policy and management.
Acknowledgements
The author would like to thank the Department of Geography at Texas Tech University,
Texas, USA for their generous assistance in enabling him to acquire a high-resolution
TerraServer imagery for the study area which was used as part of this study. Special thanks
Land use and cover change assessment using Remote Sensing and GIS: Dohuk City, Kurdistan, Iraq
(1998-2011)
Jambally Mohammed
International Journal of Geomatics and Geosciences
Volume 3 Issue 3, 2013 567
go to Dr. Tina Delahaunty, Associate Professor at the same department for taking great
efforts in providing guidance and in supervising major steps of the implementation of this
study.
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