**Anthropogenic Induced Geomorphological Change Along the Western Arabian Gulf Coast**

Ronald A. Loughland1, Khaled A. Al-Abdulkader1, Alexander Wyllie and Bruce O. Burwell *1Environmental Protection Department, Saudi Aramco Saudi Arabia* 

#### **1. Introduction**

190 Studies on Environmental and Applied Geomorphology

U.S. Fish and Wildlife Service. 1980. *Habitat Evaluation Procedures Handbook: Habitat as a Basis* 

U. S. Water Resources Council. 1983. *Economic and Environmental Principles and Guidelines for* 

Vannote, R.L., Minshall, G.W. , Cummins, K.W., Sedell, J.R., & Cushing, C.E. 1980. The river continuum concept. *Canadian Journal of Fisheries and Aquatic Sciences* 37:130-137. Walters, C. 1997. Challenges in adaptive management of riparian and coastal ecosystems.

Ward, J.V. & Stanford. J.A. 1983. Serial Discontinuity Concept of Lotic Ecosystems. Pages 29

Ward, J.V., Tockner, K., & Schiemer, F. 1999. Biodiversity of floodplain river ecosystems: ecotones and connectivity. *Regulated Rivers: Research & Management* 15:125–139. Welcomme, R. L. 1979. *Fisheries ecology of floodplain rivers*. Longman, London, United

WEST Consultants, Inc. 2000. *Upper Mississippi River and Illinois Waterway cumulative effects* 

Whited, D.C., Lorang, M.S., Harner, M.J., Hauer, F.R., Kimball, J.S., & Stanford, J.A. 2007.

Wiley, M.J., Osborne, L.L., & Larimore, R.W. 1990. Longitudinal structure of an agricultural

Williams, B. K., Szaro, R. C., and Shapiro, C. D. 2009. *Adaptive Management: The U.S.* 

*Canadian Journal of Fisheries and Aquatic Sciences* 47:373-384

U.S. Department of the Interior, Washington, DC.

and Wildlife Service, Department of Interior, Washington, D.C.

http://www.fws.gov/policy/ESMindex.html

Council, The White House, Washington, D.C.

http://www.consecol.org/vol1/iss2/art1/

Rock Island District, Rock Island, Illinois.

Science, Ann Arbor, Michigan.

Kingdom. 325 pp.

*Ecology* 88:940–953.

*for Environmental Assessment: 101 ESM*. Division of Ecological Services, U.S. Fish

*Water and Related Land Resources Implementation Studies*. U.S. Water Resources

*Conservation Ecology* [online]1(2):1. Available from the Internet. URL:

– 42 in T.D. Fontaine and S.M. Bartell eds. *Dynamics of Lotic Systems*, Ann Arbor

*study, Volume 1 and Volume 2*. Environmental Report #40 for the Upper Mississippi River – Illinois Waterway System Navigation Study. U.S. Army Corps of Engineers,

Climate, hydrologic disturbance, and succession: drivers of floodplain pattern.

prairie river system and its relationship to current stream ecosystem theory.

*Department of the Interior Technical Guide*. Adaptive Management Working Group,

The term "Anthropocene" (the geological age since the industrial revolution) popularized by the Nobel Prize winner Paul Crutzen is apt for the change that has occurred along the Saudi Arabian Coast of the Arabian Gulf. Goudie and Viles (2010) expand on this concept emphasizing the impact of man on the landscape. This Chapter identifies and quantifies changes in the coastal ecosystems of the Arabian Gulf since 1967, and highlights those remaining valuable natural habitats and environmental assets. There is a paucity of data on coastal changes along the Western Arabian Gulf coast, possibly due to restricted access to coastal areas. The authors however have had a unique opportunity to undertake repeated visits to coastal areas and with the use of remote sensed imagery have been able to document changes.

The genesis of this coastline is principally due to the movement of the Arabian Tectonic Plate which began in the Middle to Late Cretaceous period when it collided with the Eurasian Plate. The result of the compression caused by this collision was the subduction of the Arabian Plate during the Tertiary and the formation of what is now termed the Zagros Fault Zone located in present day Iran (AlNaji, 2009, Haq and Al-Qahtani, 2005). This, with the separation of the African Continental Plate possibly due to the thinning of the crust (Seber et al., 2009, Hansen et al., 2006, Daradich et al., 2003) resulting in a north-westerly tilting and the formation of the Arabian Gulf basin. Erosion of the uplifted plate resulted in the deposition of paleo-deltaic features clearly visible in digital elevations models derived from the space Shuttle Radar Topography Mission (SRTM) data in the current day Eastern Province of Saudi Arabia. During the Quaternary the plate became more arid and the Aeolian influence became more dominant and resulted in the formation of massive ergs that are a major landform of the Arabian Peninsula such as the Rub Al Khali Desert. The west and east coasts of the Gulf are completely different in their structure and geomorphology because of their tectonic origins.

Coastal processes are largely wind driven as the maximum significant wave height is less than 1.5 meters; maximum mean wave period of 3-5 seconds; tidal speed less than 0.3 m/s; and maximum range in tidal water level is from 0.5 – 2.5 meters (Rakha et al., 2007) which are all slight when compared to open ocean levels. This low energy environment is

Anthropogenic Induced Geomorphological Change Along the Western Arabian Gulf Coast 193

Map 1. Basic Land Cover and Land Use as at 2010. The background image of Map 1 is enhanced using a digital elevation model (DEM). Although the shadowing effect gives the impression of significant relief, in reality the landscape is relatively flat and has little impedance to the movement of Aeolian driven sands from the north to the south – see

Section 2.

confirmed by Summerfield (1991); and Viles and Spencer (1995). Current movements along the coastline are from north to south (Kampf and Sadrinasab, 2005, Brown, 1986). There are typical geomorphological long-shore drift features, such as the Ras Tanura Peninsula, as described by Davidson-Arnott (2010) that have been created by this anti-clockwise movement in the northern Arabian Gulf. These features are observed on the satellite imagery based maps of the northern coastline.

Parallel to the industrial growth of the region was the development of remote sensing technology that has allowed for a historic record of the impact of development on the coastal zone. This technology has provided a unique opportunity to document the changes in some coastal regions from a relatively pristine coastline to a highly developed coastal zone. The human population of the Saudi Gulf coastline has expanded exponentially, mostly as a result of hydrocarbon development in the Eastern Province. Residential, commercial, agricultural and industrial land use has thrived in a phase of economic development unknown in the history of Saudi Arabia and continued growth is predicted over the next two decades. The population in the Eastern Province grew from a few hundred thousand in the 1970s, approaching almost 3 million in 2010 (Lahmeyer, J.J., 2006). The Saudi Arabian Gulf coast has also changed significantly since 1967 as a result of the economic growth.

Development to meet increasing demands for residential, commercial and industrial expansion in the coastal zone is illustrated throughout the region. Recent changes in coastal geomorphology adjacent to highly developed coastal areas such as Dammam-Al-Khobar, Tarut Bay and Jubail are local examples of this development. Industry also places an enormous demand on the coastal zone for transport, ground water extraction, power generation, desalinization, sewerage and waste disposal.

Agriculture in the coastal zone (e.g., Qatif Oasis) has an indirect nutrient enrichment affect on the quality and productivity of marine waters such as those in Tarut Bay. The nutrient rich effluent originates from irrigation, particularly following fertilizer applications and can often enrich the natural biota within this coastal embayment (Basson, et. al. 1977). Map 1, Basic Land Cover and Land Use as at 2010, illustrates the development of the landscape in 2010 obtained from satellite imagery. The agriculture and development information in this map are digitized from enhanced satellite imagery; the sabkha derived by supervised classification techniques and density slicing; and partial development subjectively defined by infrastructure and land and water use.

This Chapter firstly describes the current situation and attempts to measure the change since the 1967 Corona imagery was acquired (Tarut Bay description is from 1934 and 1955). We then present a current risk matrix along with a short discussion on restoration programs, environmental awareness, public participation and the government legislative initiatives designed to protect the environment. The Chapter is concluded with a summary and conservation recommendations that will benefit the environmental assets of the Kingdom of Saudi Arabia.

#### **2. Surface geomorphology of the Eastern Province of Saudi Arabia**

The Eastern Province of the Saudi Arabian landform is characterized by sand movement across gravel plains, sabkha and limestone scarps. The landscape is dominated by sand sheets and widely rolling fossil sand dunes (Barth, 1999). The climate of the Eastern

confirmed by Summerfield (1991); and Viles and Spencer (1995). Current movements along the coastline are from north to south (Kampf and Sadrinasab, 2005, Brown, 1986). There are typical geomorphological long-shore drift features, such as the Ras Tanura Peninsula, as described by Davidson-Arnott (2010) that have been created by this anti-clockwise movement in the northern Arabian Gulf. These features are observed on the satellite

Parallel to the industrial growth of the region was the development of remote sensing technology that has allowed for a historic record of the impact of development on the coastal zone. This technology has provided a unique opportunity to document the changes in some coastal regions from a relatively pristine coastline to a highly developed coastal zone. The human population of the Saudi Gulf coastline has expanded exponentially, mostly as a result of hydrocarbon development in the Eastern Province. Residential, commercial, agricultural and industrial land use has thrived in a phase of economic development unknown in the history of Saudi Arabia and continued growth is predicted over the next two decades. The population in the Eastern Province grew from a few hundred thousand in the 1970s, approaching almost 3 million in 2010 (Lahmeyer, J.J., 2006). The Saudi Arabian Gulf coast has also changed significantly since 1967 as a result of the economic growth.

Development to meet increasing demands for residential, commercial and industrial expansion in the coastal zone is illustrated throughout the region. Recent changes in coastal geomorphology adjacent to highly developed coastal areas such as Dammam-Al-Khobar, Tarut Bay and Jubail are local examples of this development. Industry also places an enormous demand on the coastal zone for transport, ground water extraction, power

Agriculture in the coastal zone (e.g., Qatif Oasis) has an indirect nutrient enrichment affect on the quality and productivity of marine waters such as those in Tarut Bay. The nutrient rich effluent originates from irrigation, particularly following fertilizer applications and can often enrich the natural biota within this coastal embayment (Basson, et. al. 1977). Map 1, Basic Land Cover and Land Use as at 2010, illustrates the development of the landscape in 2010 obtained from satellite imagery. The agriculture and development information in this map are digitized from enhanced satellite imagery; the sabkha derived by supervised classification techniques and density slicing; and partial development subjectively defined

This Chapter firstly describes the current situation and attempts to measure the change since the 1967 Corona imagery was acquired (Tarut Bay description is from 1934 and 1955). We then present a current risk matrix along with a short discussion on restoration programs, environmental awareness, public participation and the government legislative initiatives designed to protect the environment. The Chapter is concluded with a summary and conservation recommendations that will benefit the environmental assets of the Kingdom of

The Eastern Province of the Saudi Arabian landform is characterized by sand movement across gravel plains, sabkha and limestone scarps. The landscape is dominated by sand sheets and widely rolling fossil sand dunes (Barth, 1999). The climate of the Eastern

**2. Surface geomorphology of the Eastern Province of Saudi Arabia** 

imagery based maps of the northern coastline.

generation, desalinization, sewerage and waste disposal.

by infrastructure and land and water use.

Saudi Arabia.

Map 1. Basic Land Cover and Land Use as at 2010. The background image of Map 1 is enhanced using a digital elevation model (DEM). Although the shadowing effect gives the impression of significant relief, in reality the landscape is relatively flat and has little impedance to the movement of Aeolian driven sands from the north to the south – see Section 2.

Anthropogenic Induced Geomorphological Change Along the Western Arabian Gulf Coast 195

southwards – toward the heavily populated Jubail Industrial City and the Dammam metropolitan area. This assumption has health, logistic and maintenance repercussions on

Map 2. Sand Transportation Zones affected by Prevailing Winds. (Adapted from Barth,

Natural coastal change in this relatively low energy environment would involve the transportation of marine sediments and terrestrial sands from north to south over an extended period of time. Mobile dune systems would be expected to traverse the landscape and be initially arrested and slowed by sabkha and surface water with the following dunes

2001, Image Global Land Cover Landsat circa 2000)

the populous of the region.

Province has changed over time with cyclic periods of changing temperature and moisture regimes (Chapman, 1971). It is currently in an arid phase where temperatures range from highs of 47°C in summer to lows of 3°C in winter with restrictive rainfall of less than 100 mm per annum. Wind patterns play a major role in the natural surface landscape development. Holm (1960), Chapman (1971) and Barth (1999 and 2001) all refer to the importance of the wind regime in the movement of sand across the region. The dominant winds come from high energy north-west direction sourced from the Mediterranean and occur from November to February with equally high energy summer Shamals from June to August and are primarily responsible for the inland movement of sand across the Province. Evidence of the directional influence of the prevailing winds creates striations caused by aeolian erosion and are clearly visible on exposed rock (see Figure 1). North of Dammam, coastal convection winds tend to move sand inward before it is transported south, whereas south of Dammam the shallower Gulf of Salwa has lesser convection influence and the sand dunes occur closer to the coast.

Fig. 1. Exposed Aeolian Weathering at Dhahran

Barth (2001) suggests four zones of sand balance within the Eastern Province (see Map 2). There is a potential sand deficit to the north; a negative sand budget in an area that is being denuded of vegetation caused by overgrazing resulting in the reactivation of fossil dunes; a balanced sand budget where sand coming in from the north is equal to sand leaving to the south; and a region of accumulation to the south. The background LANDSAT image also illustrates the generalized landforms based on the presence of absence of sand in the regime (Map 3). Another illustration of this sand movement across the region is the changes suggested by Barth (1999). He suggests that overgrazing has reduced the vegetation cover to such an extent that previously stable fossil dunes have once again become active. It is not unreasonable to assume that the dominant winds will likely increase the sand movement

Province has changed over time with cyclic periods of changing temperature and moisture regimes (Chapman, 1971). It is currently in an arid phase where temperatures range from highs of 47°C in summer to lows of 3°C in winter with restrictive rainfall of less than 100 mm per annum. Wind patterns play a major role in the natural surface landscape development. Holm (1960), Chapman (1971) and Barth (1999 and 2001) all refer to the importance of the wind regime in the movement of sand across the region. The dominant winds come from high energy north-west direction sourced from the Mediterranean and occur from November to February with equally high energy summer Shamals from June to August and are primarily responsible for the inland movement of sand across the Province. Evidence of the directional influence of the prevailing winds creates striations caused by aeolian erosion and are clearly visible on exposed rock (see Figure 1). North of Dammam, coastal convection winds tend to move sand inward before it is transported south, whereas south of Dammam the shallower Gulf of Salwa has lesser convection influence and the sand

Barth (2001) suggests four zones of sand balance within the Eastern Province (see Map 2). There is a potential sand deficit to the north; a negative sand budget in an area that is being denuded of vegetation caused by overgrazing resulting in the reactivation of fossil dunes; a balanced sand budget where sand coming in from the north is equal to sand leaving to the south; and a region of accumulation to the south. The background LANDSAT image also illustrates the generalized landforms based on the presence of absence of sand in the regime (Map 3). Another illustration of this sand movement across the region is the changes suggested by Barth (1999). He suggests that overgrazing has reduced the vegetation cover to such an extent that previously stable fossil dunes have once again become active. It is not unreasonable to assume that the dominant winds will likely increase the sand movement

dunes occur closer to the coast.

Fig. 1. Exposed Aeolian Weathering at Dhahran

southwards – toward the heavily populated Jubail Industrial City and the Dammam metropolitan area. This assumption has health, logistic and maintenance repercussions on the populous of the region.

Map 2. Sand Transportation Zones affected by Prevailing Winds. (Adapted from Barth, 2001, Image Global Land Cover Landsat circa 2000)

Natural coastal change in this relatively low energy environment would involve the transportation of marine sediments and terrestrial sands from north to south over an extended period of time. Mobile dune systems would be expected to traverse the landscape and be initially arrested and slowed by sabkha and surface water with the following dunes

Anthropogenic Induced Geomorphological Change Along the Western Arabian Gulf Coast 197

Some coastal habitats are under severe threat as a result of coastal development, and these areas are mostly within close proximity to human development or activities. Examples include salt marsh, mangrove and seagrass habitat areas. As mangroves have limited distribution, occurring in the central and northern areas within embayments surrounded by major development, they are under even greater risk of impact. The last major stands of mangrove occur in the Tarut and Musalmiyah Embayments with the largest trees occurring on and around Tarut Island. These mangrove ecosystems have been subjected to various impacts as a result of coastal development, with the most serious being smothering by land filling and as a result all mangrove habitats should be considered for immediate protection. Simultaneously aggressive mangrove rehabilitation programs need to be conducted to safeguard the genetic diversity of the mangrove populations and sustain fisheries and bird

Subtidal muddy and sandy habitats are productive components of the marine ecosystem and are often ignored because attention usually focuses on more colorful and high profile habitats such as coral reefs. Seagrass habitats are widespread within the low energy subtidal areas of the coast and unfortunately vast areas of subtidal habitat are impacted each year through dredging and reclamation work. Reducing the footprint of dredging and reclamation operations on the productive shallow water habitats of the Gulf would be environmentally beneficial. Avoidance of nonessential marine dredging and reclamation works within these areas is the best strategy to minimize damage to these ecosystems.

Aerial photography and freely available satellite imagery were used to determine coastal

All LANDSAT satellite imagery used was downloaded with geo-location properties included. ASTER data were geo-referenced using the satellite ephemeral data and block adjusted where necessary. The 1934 aerial photography was 3rd order polynomially georeferenced using common features located on the 1967 Corona imagery and the 1955 uncontrolled mosaic was triangulated to the same Corona data. All data were projected to

The coastline for each data set was determined using heads-up digitizing techniques from data enhanced to discriminate the land-water interface. Land use/cover classes (developed, agriculture and partial developed) were captured in the same way. Caution was exercised in compiling coastline changes due to the differing spatial resolutions of the imagery used; the methods of geo-location; and the state of the marine environment at acquisition. Some adjustments were necessary to increase the accuracy of the data. From the initial observations of the imagery it became obvious that there had been little change between 1934, 1955 and 1967 with minor changes detected in the 1972/73 data. A base coastline was established using the 1967 Corona data set that covered 95% of the coastal region of the Saudi Arabian Gulf. The area of sabkha was initially determined by Mah (2004) using supervised classification techniques. Small areas of in-fill were determined using a density slicing technique and both results combined into a single dataset. All coastal and land cover

**4. Detecting change over time along the Gulf coastline** 

change. These types of data and related dates are listed in Table 1.

UTM Zone 39 in WGS84 datum.

**3. Development of the coastal zone** 

populations.

continuing their southeasterly journey. However, transitional sands are being severely impacted through development requirements contributing to a lessening of the balanced sand budget referred to previously. The natural process pales into insignificance when the anthropogenic changes that have occurred since 1967 are taken into consideration.

Map 3. Generalized Geomorphologic Units of the Eastern Province (Image Global Land Cover Landsat circa 2000)
