Increased Anthropogenic Activity in the Mediterranean Since the Opening of the Suez Canal

Abstract

Humans depend on oceans and seas’ marine ecosystems for important and valuable goods and services, but human use has also altered the marine environment through direct and indirect means. Land-based and ocean-based human activities vary in their intensity of impact on the marine environmental conditions and their spatial distribution across the scape. Since opening the Suez Canal, the spatial distribution of such a human-made environmental change needs to be understood and quantified to be able to evaluate tradeoffs between the canal and the protection of the Mediterranean marine ecosystem. Such temporal and spatial evaluation will help to improve and rationalize the spatial management of the Mediterranean Sea of human activities. Evaluation of the ecological impact of the Suez Canal on the Mediterranean Sea requires a method for translating the impact into marine impacts and spatial data of the activities.

Humans depend on oceans and seas’ marine ecosystems for important and valuable goods and services, but human use has also altered the marine environment through direct and indirect means.¹ Land-based and ocean-based human activities vary in their intensity of impact on the marine environmental conditions and their spatial distribution across the scape. Since opening the Suez Canal, the spatial distribution of such a human-made environmental change needs to be understood and quantified to be able to evaluate tradeoffs between the canal and the protection of the Mediterranean marine ecosystem. Such temporal and spatial evaluation will help to improve and rationalize the spatial management of the Mediterranean Sea of human activities. Evaluation of the ecological impact of the Suez Canal on the Mediterranean Sea requires a method for translating the impact into marine impacts and spatial data of the activities.

The Mediterranean Sea is a marine biodiversity “hotspot” threatened by historical and current pressures that have led to significant changes in marine ecosystems and conflict users (Coll et al., 2012; Lotze et al., 2010).² Since opening the Suez Canal in 1869, with such intense pressure from multiple users and stressors, the Mediterranean is characterized as a sea “under siege.” Whereas shipping as a main human footprint at sea is a powerful means of the global economy, the majority of alien species in the eastern Mediterranean entered through the Suez Canal.

The central role of the Mediterranean in the historic maritime scene was diminished following the geographical discoveries of the fifteenth century, but it regained its prominence when the Suez Canal opened in 1869. The development of the Middle East oil field and the ascendance of the Southeast Asian economies in the latter part of the twentieth century reasserted the Mediterranean as a major shipping route. Today, “Suez Canal” is a subject that has captured the imagination of both academics and politicians and is often presented as part of a narrative of technological progress in the nineteenth century, shifted the Mediterranean realm of human activity. As a result of the opening of the Suez Canal, the human impact on the marine environment of the Mediterranean Sea has significantly increased, which has led to an increase in activity on land as well as an increase in marine activity, mainly related to shipping in the region. The marine-human pressures vary in their intensity of impact on the marine ecosystems of the Mediterranean Sea (see Fig. 2) and their spatial distribution across the seascape depends on the coastal human population (see Fig. 1). Understanding and quantifying the spatial distribution in local and regional scales of change in human impact since opening the Suez Canal is needed for the evaluation of tradeoffs between human uses of the Mediterranean Sea and marine ecological status. Such mapping helps improve the spatiotemporal management of the Mediterranean Sea.³

Fig. 1

Population density in the Mediterranean Sea basin, 2008⁴

Fig. 2

Spatial distribution of cumulative human pressures to marine ecosystems of the Mediterranean Sea⁷

Anthropogenic Activity in the Mediterranean Sea

The total population of the Mediterranean countries grew from 276 million in 1970 to 412 million in 2000 (a 1.35% increase per year) and 466 million in 2010. The population is predicted to reach 529 million by 2025. Four countries account for about 60% of the total population: Turkey (81 million), Egypt (100 million), France (62 million), and Italy (60 million). The Mediterranean region’s population is concentrated near the coasts. More than a third live in coastal administrative entities totaling less than 12% of the surface area of the Mediterranean countries. The population of the coastal regions grew from 95 million in 1979 to 143 million in 2000. It could reach 174 million by 2025. The concentration of population in coastal zones is heaviest in the western Mediterranean, the western shore of the Adriatic Sea, the eastern shore of the Aegean-Levantine region, and the Nile Delta. Overall, the concentration of population in the coastal zone is higher in the southern Mediterranean countries. This is also where the variability of the population density in the coastal zone is highest, ranging from more than 1000 people/km² in the Nile Delta to fewer than 20 people/km² along parts of coastal Libya.

Mapping Human Impacts in the Mediterranean Sea

Marine ecosystem management requires spatial and temporal information about current impacts and their causes. The first step toward understanding the impact of the Suez Canal as a human footprint on the Mediterranean marine environment is to determine the impact of individual and cumulative factors of human activity on the sea (see Fig. 2). The opening of the Suez Canal led to the development of the maritime industry and played an important role in globalization since the distances between Asia and the European continent were significantly reduced. Before the opening of the Suez Canal, for example, the countries of the Levantine region were more “isolated.“ The opening of the Suez Canal and the development of maritime industries led to the development and accessibility of the Levantine region to the world.

Figure 3 highlights the cumulative impacts of 22 human activities, such as shipping, invasive species, oil spills, and more, with direct impact on the Mediterranean Sea environment. The Alboran and Levantine seas have the highest average of anthropogenic cumulative impact, the western Mediterranean and the Black Sea the lowest. Most of Egypt’s and the southern part of Israel’s coastlines had medium–high to very high impact. Areas subject to high impact are: 20% of the entire Mediterranean Sea and 60–99% of the territorial waters of EU member states. Only less than 1% remains relatively unaffected by human activities.⁵ Regions of medium–high to very high impact (20.5% of the total area) are found within the Alboran Sea, the Gulf of Lyons, the Sicily Channel and Tunisian Plateau, the Adriatic Sea, off the coasts of Egypt and Israel, along the coasts of Turkey, and within the Marmara and the Black Sea (Fig. 2). Areas of very low to low impact account for a total of 13.6% of the total surface area and are present within the central Tyrrhenian Sea, parts of the northern and central Adriatic Sea, the southern Levantine Sea, and the eastern and western sides of the Black Sea (Fig. 2). A majority (65.9%) of the Mediterranean and the Black Sea are subject to the medium cumulative impact.⁶

Fig. 3

Average impact scores for each stressor in 2013 by ecoregions of the Mediterranean Sea¹⁰

As shown in Fig. 2, the coastal zone of the Nile Delta and the northern outlet of the Suez Canal is characterized by a high level of anthropogenic pressure on the marine ecosystem. The high-pressure zone extends from the western coast of Egypt to the southern coast of Israel. Moreover, the opening of the canal led to the development of new sea routes in the Mediterranean and to many ships carrying various types of cargo, thus creating new pressure hotspots on the marine environment of the Mediterranean. As a result, various sources of pollution appeared along the new sea routes, such as oil spills,⁸ light pollution,⁹ etc. In Fig. 2, the trace of paths is clearly visible along the central part of the Mediterranean Sea.

Mediterranean Sea Stressors

All Mediterranean ecoregions are influenced by both natural climatic and anthropogenic factors, but the relative influence of various individual factors differs significantly in different ecoregions of the Mediterranean Sea (Fig. 2). Anthropogenic-climatic factors contribute most to the cumulative impact in the Mediterranean ecoregions (Fig. 3), although their contribution is relatively small in the Alboran and Adriatic Seas, for example. Direct impacts from human activities at sea, such as bottom fishing, and ocean pollution, as well as from land, are the main activities that contribute to cumulative impacts in the Mediterranean. The Levantine region represents a hotspot of environmental problems in the Mediterranean. Sea level rise is one of the significant problems in this region, accounting for 47% of all cumulative impacts. Organic, inorganic, and nutrient pollution is mainly concentrated in the Levantine region. Nighttime light pollution, despite having a minor impact on much of the Mediterranean, is a significant contributing factor. As expected, the problem of invasive species in the Levantine region is a hotspot and accounts for 37% of the problems in the entire Mediterranean. Many factors, including climatic factors, may be secondary products of the opening of the Suez Canal, but also the definition of change, such as rising ocean levels and biophysical changes in seawater, can also affect the operation of the Suez Canal.

The management and conservation of the Mediterranean region require synthesis of spatial data on the distribution and intensity of human activities and the overlap of their impacts on marine ecosystems. The analytical process and maps provide flexible tools for regional and Mediterranean efforts to allocate conservation resources; to implement ecosystem-based management; and to inform marine spatial planning, education, and basic research in the region.

Suez Canal

One of the main influences of the opening of the Suez Canal was manifested in the large number of ships in the southeastern Mediterranean. Figure 4 shows a map of the density of the total flow of ships in the Suez Canal area for 2020 (data from marine traffic).

After its opening and later expansion, the canal became one of the main ship arteries not only in the Mediterranean and Red Seas but also throughout the world. On average over the past 10 years, an average of 15,000–19,000 ships pass through the Suez Canal per year, or 40–50 per day (Fig. 5). Approximately two-thirds of the total flow of incoming and outgoing ships sail toward the Black Sea, the Mediterranean Sea, and the Strait of Gibraltar, and a third is distributed to the ports of the Levantine countries. The capacity of the Suez Canal, which on average can allow for one ship to pass in one direction in most sections, leads to some ships being forced to wait in line.

Fig. 4

Map of the overall shipping traffic density in the vicinity of Suez Canal in 2020¹¹

Fig. 5

The number of ships that passed through the Suez Canal in a year¹²

Oil Pollution

The shipping industry is the backbone of global trade and value chain, and the Suez Canal is one of the main arteries.¹³ One of the negative consequences is the release of oil and oil products, accidentally or intentionally spilled from ships.¹⁴ Since the late 1960s, scientists have recognized that maritime transport is the main source of oil pollution in the oceans and, in particular, one of the greatest threats to the Mediterranean environment.¹⁵

As shown in Figs. 6 and 7, the Suez Canal area is mainly due to a high concentration of deliberate releases rather than oil spills from tankers. Moreover, a high concentration of pre-drainage plumes can also be traced from the Suez Canal in accordance with the dominant routes toward the Mediterranean Sea and the Aegean Sea.

Fig. 6

The distribution of 385 Regional Marine Pollution Emergency Center (REMPEC) spills in the Mediterranean Sea for the period 1977–2000¹⁶

Fig. 7

The distribution of 2066 European Maritime Safety Agency (EMSA) oil spills in the Mediterranean Sea for the period 2015–2017¹⁷

Artificial Nighttime Light Pollution

Artificial lights at night pose a major threat to multiple species. However, this threat is often disregarded in conservation management and action because it is difficult to quantify its effect. The increasing availability of high spatial-resolution satellite images may enable us to better incorporate this threat into future work, particularly in highly modified ecosystems such as the coastal zone,¹⁸ and assessment of the shipping activities (Polinov et al., 2022) (Fig. 8).

Fig. 8

Nighttime light pollution in the Mediterranean region. Each color represents domination of artificial lights in specific years over others: Blue = 1992, Green = 2003, Red = 2013, White = no significant changes, Black = no artificial lights

Conclusion

A new era of maritime activity in the Mediterranean was launched with the opening of the Suez Canal. Due to increased ship traffic, pressure increased on the surface of the sea, in the water column, as well as on the seabed. Despite the advancement of science and access to vast amounts of data, the assessment of human activity remains little studied. The impact of human activity has manifested itself not only in the increased number of ships passing through the Suez Canal, but also in local problems surrounding the canal, while most of them could still be defined as a research gap.

Notes

• 1. Benjamin S. Halpern, Shaun Walbridge, Kimberly A Selkoe, Carrie V. Kappel, Fioenza Micheli, Caterina D’Agrosa, John F. Bruno, et al., “A Global Map of Human Impact on Marine Ecosystems,” Science 319, no. 5865 (2008): 948–52. https://doi.org/10.1126/science.1149345.

• 2. Fiorenza Micheli, Benjamin S. Halpern, Shaun Walbridge, Saul Ciriaco, Francesco Ferretti, Simonetta Fraschetti, Rebecca Lewison et al., “Cumulative Human Impacts on Mediterranean and Black Sea Marine Ecosystems: Assessing Current Pressures and Opportunities,” PLoS ONE, 8, no. 12 (2013): e79889. https://doi.org/10.1371/journal.pone.0079889.

• 3. Benjamin S. Halpern and Rod Fujita, “Assumptions, Challenges, and Future Directions in Cumulative Impact Analysis,” Ecosphere 4, no. 10 (2013): art 131. https://doi.org/10.1890/ES13-00181.1.

• 4. “Population Density and Urban Centers in the Mediterranean Basin,” GRID Arendal, 2013. https://www.grida.no/resources/5900 (accessed October 24, 2021).

• 5. Benjamin S. Halpern, Melanie Frazier, John Potapenko, Kenneth S. Casey, Kellee Koenig, Catherine Longo, Julia Stewart Lowndes et al., “Spatial and Temporal Changes in Cumulative Human Impacts on the World’s Ocean,” Nature Communications 6 (2015): art 7615. https://doi.org/10.1038/ncomms8615.

• 6. Micheli et al., “Cumulative Human Impacts.”

• 7. Ibid.

• 8. Guido Ferraro, Annalia Bernardini, Matej David, Serge Meyer-Roux, Oliver Muellenhoff, Marko Perkovic, Dario Tarchi, and Kostas Topouzelis, “Towards an Operational Use of Space Imagery for Oil Pollution Monitoring in the Mediterranean Basin: A Demonstration in the Adriatic Sea,” Marine Pollution Bulletin 54, no. 4 (2007): 403–22. https://doi.org/10.1016/j.marpolbul.2006.11.022; Guida Ferraro, Serge Meyer-Roux, Oliver Muellenhoff, M. Pavliha, J. Svetak, Dario Tarchi, and Kostas Topouzelis, “Long Term Monitoring of Oil Spills in European Seas,” International Journal of Remote Sensing 30, no. 3 (2009): 627–45. https://doi.org/10.1080/01431160802339464; Semion Polinov, Revital Bookman, and Noam Levin, “Spatial and Temporal Assessment of Oil Spills in the Mediterranean Sea,” Marine Pollution Bulletin 167 (2021): 112338. https://doi.org/10.1016/j.marpolbul.2021.112338.

• 9. Michael H. Depledge, Céline A. J. Godard-Codding, and Robert E. Bowen, (2010) “Light Pollution in the Sea,” Marine Pollution Bulletin 60, no. 9 (2010): 1383–85. https://doi.org/10.1016/j.marpolbul.2010.08.002; Chao Sun, Yongxue Liu, Saishuai Zhao, and Song Jin, “Estimating Offshore Oil Production Using DMSP-OLS Annual Composites,” ISPRS Journal of Photogrammetry and Remote Sensing 165 (2020): 152–71. https://doi.org/10.1016/j.isprsjprs.2020.05.019; Semion Polinov, Revital Bookman, and Noam Levin, “A Global Assessment of Night Lights as an Indicator for Shipping Activity in Anchorage Areas,” Remote Sensing 14, no. 5 (2022): 1079. https://doi.org/10.3390/rs14051079.

• 10. Based on supplementary material 3 of Halpern et al. “Spatial and Temporal Changes.”

• 11. “Marine Traffic.” www.marinetraffic.com (accessed April 9, 2022).

• 12. “Suez Canal Authority.” https://www.suezcanal.gov.eg/English/Navigation/Pages/NavigationStatistics.aspx (accessed April 9, 2022).

• 13. Jihong Chen, Wentao Bian, Zheng Wan, Zaili Yang, Huiying Zheng, and Paopao Wang, “Identifying Factors Influencing Total-Loss Marine Accidents in the World: Analysis and Evaluation Based on Ship Types and Sea Regions,” Ocean Engineering 191 (2019): 106,495. https://doi.org/10.1016/j.oceaneng.2019.106495; G. Zodiatis, M. De Dominicis, L. Perivoliotis, H. Radhakrishnan, E. Georgoudis, M. Sotillo, R. W. Lardner et al., “The Mediterranean Decision Support System for Marine Safety Dedicated to Oil Slicks Predictions,” Deep-Sea Research Part II: Topical Studies in Oceanography 133 (2016): 4–20. https://doi.org/10.1016/j.dsr2.2016.07.014.

• 14. Jeff B. Curtis, “Vessel-Source Oil Pollution and Marpol 73/78: An International Success Story?” Environmental Law, 15, no. 4 (1985): 679–710. https://www.jstor.org/stable/43265739; Tsz Leung Yip, Wayne K. Talley, and Di Jin, “The Effectiveness of Double Hulls in Reducing Vessel-Accident Oil Spillage,” Marine Pollution Bulletin 62, no. 11 (2011): 2427–32. http://doi.org/10.1016/j.marpolbul.2011.08.026.

• 15. J. Teal, “Oil Spill Studies: A Review of Ecological Effects,” Environmental Management 8, no. 1 (1984): 27–43; Roberto Danovaro, “Pollution Threats in the Mediterranean Sea: An Overview,” Chemistry and Ecology 19, no. 1 (2003): 15–32. https://doi.org/10.1080/0275754031000081467; Ferraro et al., “Long Term Monitoring of Oil Spills.”.

• 16. Polinov, Bookman, and Levin, “Spatial and Temporal Assessment of Oil Spills in the Mediterranean Sea.”

• 17. Ibid.

• 18. Tessa Mazor, Noam Levin, Hugh P. Possingham, Yaniv Levy, Duccio Rocchini, Anthony J. Richardson, and Salit Kark, “Can Satellite-Based Night Lights Be Used for Conservation? The Case of Nesting Sea Turtles in the Mediterranean,” Biological Conservation 159 (2013): 63–72. https://doi.org/10.1016/j.biocon.2012.11.004.