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Qattara Depression
Ale
xa
nd
ria
Mediterranean Sea
El-Alamein
Western Desert
Easte
rn D
esert
Matrouh
Matrouh
Moghra Oasis
0 40 80 120 16020Km
29°20'E29°10'E29°0'E
30°50'N
30°40'N
30°30'N
30°20'N
0 5 10 15 202.5Km± OBR core zone
OBR buffer zone
OBR transition zone
29°20'E29°10'E29°0'E
30°50'N
30°40'N
30°30'N
30°20'N
0 5 10 15 202.5Km± OBR core zone
OBR buffer zone
OBR transition zone
Land use/cover change (LUCC) is considered one of the most
important environmental issues of global concern. The
Northwestern desert of Egypt has been subjected to new
activities that may have led to changes in the landscape and
might have influenced the distribution of important species.
The main objectives of the current study are to: 1) Map LULC
in the region between 1988 and 2011; and 2) use the produced
LULC maps to predict the potential changes in the landscape
by year 2023 using the Markov chain-Cellular Automata
integrated approach.
Land use/land cover change analysis and prediction in the northwestern coastal desert of Egypt
Marwa Waseem Halmy1*, Paul E. Gessler2, Jeff Hicke2, Boshra B. Salem1
1Alexandria University, EGYPT; 2University of Idaho, USA (*email: [email protected])
I. Introduction III. Methods
II. Study Area
V. Conclusion
The study area is part of the Western Desert of Egypt located
to the west of Alexandria city extending 40 km westward to El-
Alamein and stretching 70 km from the Mediterranean coast to
Moghra Oasis (Fig. 1). This part of Egypt has been subjected
to different levels of modification. Until recent times grazing
and rain-fed agriculture constituted the main land use activities
in the area. Recently new land use forms have been practiced
in the area including tourism and irrigated agriculture.
Fig 1. Location of study area: a) the administrative boundaries of the
Egyptian governorates; b) part of the Northwestern coastal desert showing
location of the study area; and c) subset of Landsat TM imagery from 2011
representing the study area showing location of Omayed Biosphere
Reserve (OBR), core zones shown in red, buffer zone in green and
transition zone in blue.
Fourteen land use/land cover (LULC) classes were mapped for
three dates, 1988, 1999, and 2011. Landsat TM data and ancillary
data were classified using random forests (RF) ensemble
classification approach (Fig 2). The LULC maps produced were
then used for predicting future land use change using integrated
Markov-CA model. This was conducted in three steps: 1) applying
the Markov chain analysis to the 1988, 1999, and 2011 LULC
maps for calculating transition matrices; 2) calculating transition
potential maps for LULC classes; and 3) application of CA model
to the transition matrices and the transition potential maps to
predict the spatial distribution of LULC.
Fig 2. Framework of the steps used in the analysis of the data.
Random forest (RF) classifier produced LULC classification with
an overall accuracy over 90% and kappa index of more than 0.9.
The use of the Markov Chain-Cellular automata model was
successful in providing prediction of the LULC distribution for the
year 2011 and was comparable to the actual for 2011.
Year
(stage)
Overall
accuracy
Kappa
Mean
omission
/class (%)
Mean
commission/class
(%)
1988 (first) 92.53 0.92 6.96±7.46 7.90± 8.62
1999 (second) 93.77 0.93 5.98±4.07 5.09±6.46
2011 (third) 97.30 0.97 2.75±4.13 3.02±3.51
Table 1. Overall accuracy, kappa statistic, mean per class omission
and commission error for land use/land cover classification of the year
1988, 1999, and 2011.
The analysis of the distribution of LULC classes over the three
dates revealed dynamic changes in LULC (Fig 3 & Table 2). The
developmental activities resulted in three different stags each
dominated by different land uses. Grazing, non-irrigated
agriculture (rain-fed and orchards) and quarrying dominating the
first stage; summer resorts, built-up areas, both non-irrigated
agriculture (rain-fed and orchards) and irrigated agriculture and
quarrying dominating the second stage; and irrigated
agriculture, summer resorts, built-up areas and quarrying
dominating the third stage. The potential distribution of the LULC
classes by 2023 shows predicted expansion in the croplands
westward and northward. An expected increase in quarries and in
residential centers in the area is also revealed.
Fig 3. Land use/land cover distribution in the landscape
resulting from classification of Landsat TM image over three
different stages.
Period Persistence (%) Change (%)
1988-1999 88.50 11.50
1999-2011 88.40 11.60
Table 2. change and persistence percentage of the
landscape over the periods 1988-1999, and 1999-2011.
The analysis of the change in the spatial distribution of the
LULC reveals that the landscape has become patchier and
less naturalized. The natural land cover (rangelands, coastal
dunes, mixed barren lands, and wet & marsh areas) continues
to suffer from dissection and attrition, while the artificial and
semi-artificial land covers (resorts, built-up areas, quarries and
croplands) are undergoing creation and aggregation (Fig 4).
a)
-4-2
02
4
b)
-4-2
02
4
BU RE CR OA RL WT RS SM CD SF BA QR GD
c)
LULC
Are
a (%
) of
the
land
scap
e
-4-2
02
4
Fig 5. Net change for each LULC class as percentage of the
landscape area over the period a) 1988-1999; b) 1999-2011;
and c) 1988-2011.
The natural land cover is experiencing loss to the new land
uses. Built-up areas, croplands, resorts, and quarries each
exhibit gain over the entire study period (Fig 5), while
rangelands, the barren mixed lands and the coastal dunes
are declining. The shift towards the artificialization of the
landscape is expected to continue in the future as revealed
by the index of landscape conservation (ILC) (Fig 6). The
changes the landscape has experienced might continue
and will likely impact the distribution of species in the area.
Random forests succeeded in classifying the LULC using
integrated Landsat TM data with environmental variables.
This indicates the merit of using this technique in mapping
LULC in similar arid ecosystems. The change occurring in the
area is a reflection of the development strategy aiming at
expanding outside the heavily populated Delta through
developing the desert fringes. The resorts development on
the coastal dunes and the establishment of irrigation system
are likely the main causes of changes in the area as revealed
by the study. These changes are expected to continue and
might impact the species distribution in the area. This needs
to be further assessed taking into account the influence of
climate change. Understanding how the changes in the
landscape and climate change might influence important
species distribution will help guide conservation planning in
the area. The study can serve as guidelines for other studies
attempting to project LUCC in arid lands experiencing similar
land use changes.
IV. Results
1999
2011
LULC Maps
1988, 1999, 2011
Landsat TM 5
Integrated
spectral &
ancillary data
Classification
Random
Forests
Breiman (2001)
LULC prediction
using Markov-
chain/Cellular
automata
Projected LULC
maps 2023
1988
Fig 6. Index of Landscape Conservation (ILC) estimated for the
whole landscape over the years 1988, 1999, 2011 and 2023.
Fig 4. Past and potential change processes
working over the studied landscape.
a)
b)
c)
ESA Living Planet Symposium 2013, Edinburgh, UK.
0.8
0.82
0.84
0.86
0.88
0.9
0.92
1988 1999 2011 2023
ILC
Year
1988
2011
1999
Projected 2023
Attrition
Aggregation
Creation
Dissection
1988-1999
1988-2023
1999-2011
1988-2011