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The Human influence on the Mediterranean coast over the last 200 years: a brief appraisal from a geomorphological perspective

L’influence de l’Homme sur les littoraux méditerranéens sur les deux derniers siècles : un bref aperçu à partir d’une perspective géomorphologique
Edward J. Anthony
p. 219-226

Résumés

Les côtes de la Méditerranée ont été considérablement modifiées par l’Homme, surtout depuis deux siècles, entraînant leur déstabilisation géomorphologique. Les nombreux barrages et de multiples modifications touchant au fonctionnement des cours d’eau méditerranéens ont entraîné une réduction drastique des apports de sédiments nécessaires pour l’alimentation des plages et des dunes. Les littoraux et leurs plaines côtières souvent étroites ont été également massivement transformés par des ouvrages d’ingénierie, aggravant la déstabilisation. Ces modifications, notamment associées à la construction de marinas, de ports de plaisance et de plages artificielles, ont conduit à l’émergence de véritables littoraux artificiels. Les littoraux rocheux sont également de plus en plus sous la pression des constructions de résidences et d’infrastructures touristiques. La sauvegarde future des littoraux méditerranéens appelle à un meilleur ciblage des enjeux et une réévaluation des stratégies d’aménagement et de gestion.

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Notes de la rédaction

Article soumis le 21 mai 2012, accepté le 16 août 2012.

Texte intégral

I thank Christophe Morhange, Hervé Regnauld, and Mouncef Sedrati for their constructive reviews.

Introduction

1The geological context of the Mediterranean, comprising both active and passive margins, and the climate, have resulted in a highly diversified coastal morphology and active fluvial sediment supply to much of the coast. About 46% of the total length of the Mediterranean coastline (46,133 km) consists of depositional shores (Poulos and Collins, 2002), the rest consisting of rocky shores. Mediterranean rivers have commonly supplied sediments to narrow coastal barriers, sometimes with extensive lagoonal systems. On the rocky coastal sectors, narrow, stationary pocket beaches locked between bedrock headlands appear to be more stable features. On the basis of the very low tidal range and the wave regime, the Mediterranean coast may be considered as wave-dominated.

2Expressions of the relationship between Nature, cursorily defined here as the biophysical world, and Humans in the Mediterranean are ancient and diverse. The aim of this paper is to present a brief overview of the geomorphic human imprint on the Mediterranean coast over the more recent period covering the last two centuries, especially dominated by the modern era of socio-economic and cultural development strongly hinged on tourism, and which is reflected in the present fragile status of large stretches of depositional coast in the Mediterranean. This overview is necessarily incomplete, given the vast range of human interventions, both directly on the coast, and indirectly via modifications of river catchments that supply the sediment to the Mediterranean. The implications of human-induced changes in terms of the geomorphic functioning of the Mediterranean coast are briefly discussed.

Perturbation of river sediment supply and impacts on the coast

3The Mediterranean drainage basin incorporates more than 160 rivers with a catchment >200 km2, of which only a few are larger than 50 x 103 km2, an observation that emphasises the important role of the smaller rivers (Poulos and Collins, 2002). The Mediterranean river basins are characterised by high sediment yields (Vanmaecke et al., 2011). The magnitude of the important sediment supply by rivers is demonstrated by various observations (Poulos and Collins, 2002): (i) as mentioned above, nearly half (21,221 km) of the shores of the Mediterranean have been formed by sediment deposition; (ii) many Mediterranean deltas have prograded in recent times by, at least, several metres per year; and (iii) Holocene coastal (inner shelf) deposits of fluvial origin are some tens of metres thick. Overviews of changes in Mediterranean catchment characteristics induced by human activities over the last two centuries have been attempted (Poulos and Collins, 2002; Hooke, 2006). The construction of hundreds of dams around the Mediterranean Sea, especially over the last 50 years, has led to a dramatic reduction to approximately 50% of the potential (natural) sediment supply. Land-use changes in Mediterranean catchments especially land abandonment in the mountainous hinterlands has led to reforestation. Other activities have included artificial channel control and in-channel gravel and sand extraction.

4The impacts of the changes in river sediment budget on Mediterranean deltas and their adjacent shores have been documented in many case studies, notably concerning the deltas of the Nile, the Rhône, the Ebro, and the Po, fed by the largest river catchments in the Mediterranean. The most dramatic changes have been reported from the Nile delta, the fluvial sediment supply of which is considered to have been totally curtailed upstream of dams. Analyses of historical maps show that, during the 1800s, the Rosetta and Damietta delta promontories, the two modern branches of the delta, prograded by 3 to 4 km, in response to the large quantities of fluvial sediments delivered to the coast (Frihy and Lawrence, 2004). This accretion regime switched to one of erosion at the beginning of the 20th century, attributed primarily to the construction of two dams on the upper river in Aswan and barrages on the both the upper and lower Nile River that cut off almost all water discharge and the delivery of fluvial sediments to the coast (Frihy and Khafagy, 1991). Other factors have, however, also contributed to the extensive erosion of the delta shoreline during recent times. These include an abrupt decrease in water discharge and fluvial sediment yield during the 20th century resulting from low rainfall in the Nile catchment in Ethiopia and central Africa, sea-level rise, and local deltaic subsidence (El Banna and Frihy, 2009).

5The effects of sediment budget perturbations have been thoroughly documented for the Rhône delta (Antonelli et al., 2004; Maillet et al., 2006 a and b; Sabatier et al., 2006). An analysis of long-term (1841-1974) changes in the main Rhône prodeltaic lobe showed a reduction of sedimentation by a factor of 3.7, from 12.63 to 3.41 × 106 m3/a (Sabatier et al., 2006). These changes were found to result directly from a decrease in river sediment input related to a natural decreasing frequency of major floods at the end of the Little Ice Age (Arnaud-Fassetta and Provansal, 1999; Arnaud-Fassetta, 2003), reforestation of the catchment, and, since the 1950s, dam construction and dredging activities. A similar pattern has been reported from the Ebro delta, which, after several centuries of growth, evolved into an erosional regime a few decades ago as a result of the nearly total reduction of river sediment discharge due to dam construction in the lower reaches (Palanques et al., 1990). The Po delta, once subject to strong progradation, is now largely affected by chronic erosion resulting from a conjunction of reduction in sediment supply during the 20th century caused by dam constructions and riverbed sediment extractions, and subsidence caused by methane extractions and ground water abstraction (Simeoni and Corbau, 2009).

6The small Var delta on the French Riviera is a fine example of radical anthropogenic transformation of a delta (fig. 1).

Fig. 1 – A Google Earth image of the Var River delta on the French Riviera.
Fig. 1 – Une image Google Earth du delta du fleuve Var sur la Côte d’Azur.

Fig. 1 – A Google Earth image of the Var River delta on the French Riviera. Fig. 1 – Une image Google Earth du delta du fleuve Var sur la Côte d’Azur.

This is a fine example of radical human transformation of a Mediterranean delta. Changes in the course of the 20th century have included the construction of several barrages in the lower course of the river, total reclamation and extension of the delta plain through infill, and complete armouring of the shoreline for the construction of the international airport of Nice. Up to 3.5 km² of additional space was gained by reclamation of part of the steep, unstable muddy delta front. Part of this reclamation fill, including a harbour breakwater, collapsed on October 16 1979, causing numerous casualties (Julian and Anthony, 1996). The natural supply of fluvial gravel to the adjacent beaches has been completely cut off by the delta armouring, leaving present beach sediment budgets with zero natural inputs, resulting in chronic erosion that constantly needs to be contained by frequent nourishment.
Il s’agit ici d’un exemple éloquent de la transformation radicale d’un delta méditerranéen. Au cours du XXe siècle, plusieurs petits barrages ont été érigés sur le cours inférieur du Var, juste en amont du delta, et la plaine deltaïque a été complètement poldérisée et étendue pour accueillir l’aéroport de Nice, le tout ceinturé par une armure de défenses côtières. L’extension du site deltaïque, pour gagner un espace supplémentaire de 3,5 km², a été faite par le remblaiement du front deltaïque raide, composé de vases instables. Une partie de ce remblaiement, dont un port en construction, s’est effondrée le 16 octobre 1979, entraînant de nombreuses pertes de vie et des dégâts importants (Julian et Anthony, 1996). L’apport naturel de graviers fluviatiles vers les plages adjacentes s’est complètement tari, entraînant une érosion chronique de ces plages qui doivent être réalimentées périodiquement par des apports artificiels.

7Changes in the course of the 20th century included the construction of several barrages in the lower course of the Var (Julian and Anthony, 1996), reclamation and extension of the Var delta plain through infill, and armouring of the shoreline for the construction of the international airport of Nice (Anthony, 1994; Anthony and Julian, 1999). The natural supply of gravel to the adjacent beaches, especially that of Nice, has been completely cut off, leaving present beach sediment budgets with zero natural inputs, resulting in chronic beach erosion that needs to be contained by frequent beach nourishment (Anthony et al., 2011).

Modern shoreline changes induced by coastal socio-economic development

8The shores of the Mediterranean were often avoided by human societies in ancient times and in the Middle Ages for reasons of safety from invaders from the sea, from storms, and from mosquito infestation of backshore lagoons. Human appropriation of the coast has occurred to varying degrees depending on geology, technology, culture, climate and socio-economic pressures. In modern times, the occupation of many of the low-lying sectors of coast has resulted in their progressive destabilisation. Over the 20th century, this situation has been characterised in many ways and in many places in the Mediterranean by misguided patterns of development that have exacerbated coastal erosion while endangering coastal ecosystems. Problems of coastal destabilisation and erosion have, as indicated earlier, been due largely to long-term depletion of fluvial sediment. At the same time, massive engineering interventions with far-reaching consequences are products of urban, port and tourism development over the last few decades, as along the Tangiers (Sedrati and Anthony, 2007) and Tetouan coasts (Anfuso et al., 2007; Elmrini et al., 2012 a and b) of Morocco, the northeastern coast of the Nile delta (El Banna and Frihy, 2009), the Tuscany coast in Italy (Anfuso et al., 2011), the Catalonia coast in Spain (Jiménez et al., 2011) and the French Mediterranean coast (Anthony, 1994; Anthony and Sabatier, 2012, 2013), especially the low-lying barrier-lagoon Languedoc-Roussillon coast where mosquito infestation contributed to keeping development at bay until large-scale planned development involving joint state and private capital ventures was implemented in the 1960s.

9The most direct and most important development effect has been a drastic reduction of beach width due to the growth of urban fronts, and destruction of aeolian dunes (fig. 2), resulting in beach-dune sediment-budget perturbations.

Fig. 2 – Destruction of coastal dunes for the construction of tourist residences near Tetouan, Morocco (2006/5/27).
Fig. 2 – Destruction de dunes côtières près de Tétouan, Maroc (27/05/2006).

Fig. 2 – Destruction of coastal dunes for the construction of tourist residences near Tetouan, Morocco (2006/5/27). Fig. 2 – Destruction de dunes côtières près de Tétouan, Maroc (27/05/2006).

Photo courtesy of A. Elmrini.
Photo de A. Elmrini.

10A corollary of this has often been the onset of erosion, exacerbated by the incapacity of deltaic river mouths located updrift to supply fresh sediment, as seen in the previous section. Many river mouths have also been stabilised by engineering structures, and some used as leisure ports. Such development has often been relayed by the construction of groynes and breakwaters to contain erosion (fig. 3), commonly worsening the situation, generating problems downdrift that have led to a rather unfortunate multiplication of such engineering structures (Pranzini and Williams, 2013).

Fig. 3 – An example of large-scale shoreline modifications, Tuscany, northern Italy.
Fig. 3 – Un exemple de modifications du littoral à grande échelle, Toscanie, Italie du nord.

Fig. 3 – An example of large-scale shoreline modifications, Tuscany, northern Italy. Fig. 3 – Un exemple de modifications du littoral à grande échelle, Toscanie, Italie du nord.

The photographs show the Magra river mouth (a), Marina di Carrara harbour (b), Marina di Massa (c), Viareggio harbour (d), the Gombo and Morto Nuovo river mouths (e), the Arno river mouth (f), and the southern area of Marina di Pisa (g). Modified after Anfuso et al. (2011).
Les photographies montrent l’embouchure du fleuve Magra (a), le port de la Marina de Carrara (b), la Marina de Massa (c), le port de Viareggio (d), les embouchures des fleuves Gombo et Morto Nuovo (e), l’embouchure du fleuve Arno (f) et la partie sud de la Marina de Pise (g). Modifié d’après Anfuso et al. (2011).

11In countries like France and Italy, this illustrates a past situation, that has been changing in recent years, of lack of dialogue between communes, and the gap between sensible, ecosystem-based coastal management, viewed at least within the scope of sediment cells and sediment budgets, and a stilted and piecemeal administrative approach in managing the coast (Anfuso et al., 2011; Anthony and Sabatier, 2012). Urban coastal development has also strongly affected seagrass colonies that play a role in dissipating wave energy on Mediterranean shores. This is notably the case of Posidonia oceanica, largely destroyed in places by large-scale beach protection, beach nourishment, leisure harbour structures, urban waste discharge, and invasions by the seaweed Caulerpa taxifolia.

12Within this modern context of significant human impact on the Mediterranean coast, two noteworthy aspects need to be underscored: (i) there has been overall preservation of rocky shores, and (ii) coastal engineering has not just involved structural and beach nourishment solutions to problems of erosion, but also the large-scale development of entirely "artificial" shores, where the original shore type has been totally modified by humans (Anthony, 1994). Direct engineering intervention on hard-rock shores in the Mediterranean (fig. 4) is generally limited to short stretches offering suitable locations for leisure harbour development or providing foundations for the construction of small artificial beaches.

Fig. 4 – Photograph of a progressively transformed rocky coast in the Esterel Massif, French Riviera (2012/4/1).
Fig. 4 – Photographie d’une côte rocheuse en transformation progressive dans le Massif de l’Estérel, Côte d’Azur (01/04/2012).

Fig. 4 – Photograph of a progressively transformed rocky coast in the Esterel Massif, French Riviera (2012/4/1).Fig. 4 – Photographie d’une côte rocheuse en transformation progressive dans le Massif de l’Estérel, Côte d’Azur (01/04/2012).

13These are generally short embayed sectors, sometimes initially characterised by natural pocket beaches (e.g., Anthony, 1994; Bowman et al., 2009). There are, however, limited sectors of soft rocky shores that have also been significantly affected by human intervention, as on the Apulian coast of southeast Italy (Andriani and Walsh, 2007). ‘Artificial’ shorelines correspond to: (i) many leisure harbours, constructed especially since the 1980s, (ii) reclamation fill for various types of development, notably residential, as in Monaco, but also related to tourism, as in the case of marina constructions, and transport, as in the case of Nice Airport on the French Riviera (fig. 1), and (iii) artificial beaches. Artificial shores generally blend entirely with urban fronts. The term “techno coast” has been used to categorise stretches of artificial urban shores in Naples and its environs that have been modified to such an extent by engineering that the physical attributes of the original shore are no longer visible or preserved (De Pippo et al. (2008). Urban tourism in the Mediterranean over the last four decades has been characterised, in particular, by a significant development of artificial beaches, especially in the dominantly rocky sectors of the Mediterranean coast of France (Anthony, 1994) and Spain (Ojeda and Guillèn, 2008), and in Italy (Bertoni and Sarti, 2011).

Discussion and conclusions

14The coastal impacts of river-catchment modifications in the Mediterranean have been exacerbated in the 20th century by direct anthropogenic pressures on the depositional shores of the Mediterranean, following the boom in world tourism. The attractiveness of the shores of the Mediterranean basin is today highlighted by its position as the world’s leading tourism and leisure destination. Accommodating this position has involved the construction of numerous leisure harbours, and the implementation of shoreline stabilisation works. In reality, this has involved both direct shoreline appropriation by economic, notably tourism-based, development, and engineering efforts aimed at stabilising shores that are now increasingly prone to erosion from deficit in river sediment supply and perturbation of longshore drift (Pranzini and Williams, 2013).

15Rocky shores in the Mediterranean have been largely exempt from engineering. It may be argued, in some ways, that the high costs of physically modifying them has led to the preservation of over 50% of the rocky shores of the Mediterranean. Anthony (1994) showed, for instance, from Principal Components Analysis, a clear opposition in the eastern half of the highly tourism-oriented French Riviera in southeastern France, between rocky shores on the one hand, and both natural and artificial beaches, on the other. The breath-taking views offered by bold rocky shores have contributed to the attractiveness of the Mediterranean, but the extensive presence of these rocky shores, which are commonly inaccessible or untransformable, especially along the mountainous western Mediterranean, is also a factor that has brought pressure to bear on the more accessible beach, dune and barrier-lagoon sectors. The picturesque backdrop on bold shores is however, leading to increasing pressures on these shores from housing and tourist infrastructure.

16The geomorphology of the coast of the Mediterranean is characterised, thus, by, extreme natural diversity to which human societies have also contributed through large-scale modifications and the emergence of artificial shores. The geomorphic dimension of human intervention is, thus, extremely important in both the physiognomy and the stability of the Mediterranean coast and will become more so as sediment supply pressures are likely to become aggravated by sea-level rise. One outcome of the present situation of human pressures and shoreline diversity is that it embodies severe shortcomings in management that call for the rapid implementation of sound principles of integrated coastal zone management, involving both policy (e.g., Markandya et al., 2008; González-Riancho et al., 2009; Sanò et al., 2010) and hazard mitigation (e.g., De Pippo et al., 2008; Armaroli et al., 2012). There is a need to balance strategies across a wide range of levels of economic development that concern not only the prosperity of high-revenue urban shores notably open to tourism, but also low-revenue shores, generally of ecological value. Future sustainable development of the Mediterranean coast can only be achieved via an approach encompassing a wide interdisciplinary spectrum that necessarily includes coastal morphodynamic processes, fluvial source-to-coastal sink sediment considerations and coastal sediment budget calculations. This perspective will require a clear identification of the stakes of the future, including those related to the impacts of climate change, sea-level rise, especially along the deltaic coasts, and a better evaluation of management strategies that need to be deployed, including those relating to urbanisation and infrastructure development.

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Annexe

Version française abrégée

La géomorphologie des rivages de la Méditerranée illustre, par excellence, l’étroite imbrication entre la Nature et l’Homme. Le contexte tectonique de la Méditerranée, marqué par des marges aussi bien passives qu’actives et par une sismicité notable, ainsi que son climat, confèrent à ses rivages et ses nombreuses îles des caractéristiques morphologiques très diversifiés, et un régime d’apports de sédiments souvent très actif, caractérisé par le développement de nombreux deltas fertiles. Le littoral méditerranéen est, aujourd’hui, en grand partie, déstabilisé par des activités anthropiques. Depuis deux siècles, l’influence de l’Homme sur les littoraux méditerranéens a été dominée par deux faits majeurs : 1) des modifications importantes du régime des fleuves, conduisant à des perturbations du bilan d’érosion de ces fleuves et 2) une emprise directe sur le littoral par une occupation croissante, notamment de caractère urbano-touristique, et ses corollaires en termes d’ingénierie côtière. La construction de nombreux barrages, à des fins agricoles et hydro-électriques, et de multiples modifications touchant au fonctionnement de très nombreux cours d’eau méditerranéens ont entraîné une réduction drastique des apports de sédiments nécessaires pour l’alimentation des plages et des dunes. Le cas le plus remarquable est celui du Nil, avec la construction du barrage d’Assouan, mais de nombreux autres deltas sont affectés par ces rétentions de sédiments. En même temps, l’appropriation, par l’Homme, des rivages méditerranéens souvent délaissés par le passé pour des raisons de sécurité, a entraîné une déstabilisation progressive des plages et des dunes. Cette appropriation a pris de l’ampleur au XXe siècle. L’attrait touristique du littoral méditerranéen est mis en exergue par sa position aujourd’hui comme première destination de plaisance et de loisir au monde. Cette emprise de l’Homme se solde par des dérives en matière de développement économique qui, dans bien des cas, aggravent l’érosion littorale relevant de pénuries de sédiments liées aux transformations des cours d’eau pourvoyeurs. Ces modifications impliquent notamment des restructurations importantes du littoral par voie d’ingénierie. Les grands travaux de l’époque moderne concernent essentiellement l’aménagement urbain et des accompagnements à l’aménagement portuaire qui gagnent du terrain depuis quelques décennies, que ce soit pour des raisons de commerce international ou pour des loisirs. Les modifications du trait de côte, notamment associées à la construction de marinas, de ports de plaisance et de plages artificielles, ont conduit à l’émergence de véritables littoraux artificiels. Dans certains cas, la mise en place de digues et d’épis pour contenir l’érosion a eu un effet multiplicateur en déplaçant toujours le problème du bilan sédimentaire au sein des cellules de transit littoral, illustrant ainsi la déconnexion malheureuse entre ces unités sédimentaires et la gestion administrative du trait de côte axée largement sur une approche communale individuelle. Les littoraux rocheux ont été jusqu’ici très largement exempts des interventions d’ingénierie mais les pressions liées à la construction de résidences et d’infrastructures touristiques sont néanmoins de plus en plus fortes sur ce type de littoral en Méditerranée. La sauvegarde future des littoraux méditerranéens passe par une approche interdisciplinaire allant de la connaissance de leur fonctionnement morphodynamique jusqu’à la législation. Cette approche nécessitera une bonne maîtrise des données de site impliquant des études expérimentales et la modélisation, et un décloisonnement entre la dimension « physique » (géomorphologie, hydrodynamique, fonctionnement écosystémique, bilans sédimentaires) et « humaine » (gestion, aménagement, législation, développement socio-économique). Cette démarche appelle à un meilleur ciblage des enjeux du futur, y compris ceux afférant aux impacts du changement climatique, et une meilleure réévaluation des stratégies d’aménagement et de gestion, y compris la prédiction de l’ampleur et de la localisation des demandes en matière d’urbanisation et d’infrastructures côtières.

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Table des illustrations

Titre Fig. 1 – A Google Earth image of the Var River delta on the French Riviera. Fig. 1 – Une image Google Earth du delta du fleuve Var sur la Côte d’Azur.
Légende This is a fine example of radical human transformation of a Mediterranean delta. Changes in the course of the 20th century have included the construction of several barrages in the lower course of the river, total reclamation and extension of the delta plain through infill, and complete armouring of the shoreline for the construction of the international airport of Nice. Up to 3.5 km² of additional space was gained by reclamation of part of the steep, unstable muddy delta front. Part of this reclamation fill, including a harbour breakwater, collapsed on October 16 1979, causing numerous casualties (Julian and Anthony, 1996). The natural supply of fluvial gravel to the adjacent beaches has been completely cut off by the delta armouring, leaving present beach sediment budgets with zero natural inputs, resulting in chronic erosion that constantly needs to be contained by frequent nourishment. Il s’agit ici d’un exemple éloquent de la transformation radicale d’un delta méditerranéen. Au cours du XXe siècle, plusieurs petits barrages ont été érigés sur le cours inférieur du Var, juste en amont du delta, et la plaine deltaïque a été complètement poldérisée et étendue pour accueillir l’aéroport de Nice, le tout ceinturé par une armure de défenses côtières. L’extension du site deltaïque, pour gagner un espace supplémentaire de 3,5 km², a été faite par le remblaiement du front deltaïque raide, composé de vases instables. Une partie de ce remblaiement, dont un port en construction, s’est effondrée le 16 octobre 1979, entraînant de nombreuses pertes de vie et des dégâts importants (Julian et Anthony, 1996). L’apport naturel de graviers fluviatiles vers les plages adjacentes s’est complètement tari, entraînant une érosion chronique de ces plages qui doivent être réalimentées périodiquement par des apports artificiels.
URL http://geomorphologie.revues.org/docannexe/image/10654/img-1.png
Fichier image/png, 1,0M
Titre Fig. 2 – Destruction of coastal dunes for the construction of tourist residences near Tetouan, Morocco (2006/5/27). Fig. 2 – Destruction de dunes côtières près de Tétouan, Maroc (27/05/2006).
Crédits Photo courtesy of A. Elmrini.Photo de A. Elmrini.
URL http://geomorphologie.revues.org/docannexe/image/10654/img-2.png
Fichier image/png, 947k
Titre Fig. 3 – An example of large-scale shoreline modifications, Tuscany, northern Italy. Fig. 3 – Un exemple de modifications du littoral à grande échelle, Toscanie, Italie du nord.
Légende The photographs show the Magra river mouth (a), Marina di Carrara harbour (b), Marina di Massa (c), Viareggio harbour (d), the Gombo and Morto Nuovo river mouths (e), the Arno river mouth (f), and the southern area of Marina di Pisa (g). Modified after Anfuso et al. (2011). Les photographies montrent l’embouchure du fleuve Magra (a), le port de la Marina de Carrara (b), la Marina de Massa (c), le port de Viareggio (d), les embouchures des fleuves Gombo et Morto Nuovo (e), l’embouchure du fleuve Arno (f) et la partie sud de la Marina de Pise (g). Modifié d’après Anfuso et al. (2011).
URL http://geomorphologie.revues.org/docannexe/image/10654/img-3.png
Fichier image/png, 698k
Titre Fig. 4 – Photograph of a progressively transformed rocky coast in the Esterel Massif, French Riviera (2012/4/1).Fig. 4 – Photographie d’une côte rocheuse en transformation progressive dans le Massif de l’Estérel, Côte d’Azur (01/04/2012).
URL http://geomorphologie.revues.org/docannexe/image/10654/img-4.png
Fichier image/png, 1,7M
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Edward J. Anthony, « The Human influence on the Mediterranean coast over the last 200 years: a brief appraisal from a geomorphological perspective », Géomorphologie : relief, processus, environnement, vol. 20 - n° 3 | 2014, 219-226.

Référence électronique

Edward J. Anthony, « The Human influence on the Mediterranean coast over the last 200 years: a brief appraisal from a geomorphological perspective », Géomorphologie : relief, processus, environnement [En ligne], vol. 20 - n° 3 | 2014, mis en ligne le 01 janvier 2016, consulté le 27 juin 2017. URL : http://geomorphologie.revues.org/10654 ; DOI : 10.4000/geomorphologie.10654

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Auteur

Edward J. Anthony

Aix-Marseille Université – Institut Universitaire de France – CEREGE UM 34 – Europôle de l’Arbois – BP 80 – 13545 Aix-en-Provence Cedex 4 – France (anthony@cerege.fr).

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