VERGER, Fernand (2009) Zones humides du littoral français. Estuaires, deltas, marais et lagunes. Paris, Belin, 448 p. (ISBN 978-2-7011-5201-1)

Geographer and professor emeritus at the École Normale Supérieure in Paris, Fernand Verger is an internationally known pioneer in the study of coastal geomorphology and the effects of sea-level rise on coastal regions. Over the last four decades, he has directed or directly influenced many of the leading coastal geomorphologists in France and Quebec. The fruit of a productive career, Zones humides du littoral français is an impressive synthesis of over 400 pages dealing with the physical and human geography of the origins and evolution of and human interaction with the coastal wetlands of France. It is also a work of profound organizational and illustrative beauty, with hundreds of archival maps, aerial photographs and coloured plates of the most well-known wetlands in France – Mont-Saint-Michel, Carentan, Poitou, L’anse de l’Aiguillon and the Camargue are ready examples. In addition, many of the maps and diagrams drawn by the cartographer Raymond Ghirardi are seen here for the first time and provide scientific and general views of coastal wetlands not found in any other publication.

Thanks to Verger’s fine penmanship, Zones humides du littoral français makes refreshing reading. Like many collected essays and Festchriften, which mark the closing stages of a scientific career, it could easily have been published as an edited compilation of the numerous texts authored by Verger over the last forty years. Thankfully, this is not the case. In an age of overspecialization and unwillingness to tackle original works of synthesis, Zones humides du littoral français represents the very best of what good geography used to do so effortlessly – blend space, time and the concerns of physical and human geography in works steeped in erudite reflection.

In the first section of the book (p. 6-123), the reader is introduced to scientific literature, description, terminology, and past and current problems associated with the study of coastal wetlands. Specifically, it focuses on sea-level change over the last 10,000 years, and on wetland soils, macro- and micro-wetland forms, flora and fauna, and past and current coastal wetland management practices. The second part of the book (p. 124-399) is divided into 15 chapters familiarizing the reader with various coastal wetlands. The chapters are organized spatially, beginning with the Flemish wetlands of the Pas-de-Calais and Picardie on the Atlantic coast, the coastal wetlands of Aquitaine in the south and finally, those on the eastern side of the country. From here, the reader follows France’s Mediterranean coastline, from Canet to the Rhone delta, to the coastal wetlands of the Côte d’Azur. Verger’s final chapter – a rare treat, indeed – explores the coastal wetlands of Corsica.

At a time of scientific uncertainty about the long-term future of coastal wetlands against a background of climate change, sea level-rise and human activity, Zones humides du littoral français affords a rare opportunity for readers to understand the importance of avoiding sweeping generalizations about coastal wetlands, their origins, and physical and anthropogenic development. Although France is a relatively small country, this sequential study of its coastal wetlands illustrates the diversity of the geomorphological processes at work as well as the diverse cultural practices that have taken place and are still active in these loci.

On the urgent question of climate and sea-level change, Verger emphasizes that it is important to remember that gradual sea elevation does not signify that this elevation is the same at every coastal location. The diversity of opinions concerning the effects of minor changes in sea level in coastal marshes should, in his opinion, also be underscored. Depending on the rate of sea-level rise and the amount of sediment, schorre, (vegetated marsh) can, he continues, erode or, conversely, grow (p. 33‑35). Whereas the predominant discourse among coastal geomorphologists in Quebec has for the last thirty years concentrated almost solely on erosion, in France, despite the vagueness of the recorded measurements, no-one, according to Verger, disputes that, in terms of mass and volume, the more than one-thousand-square-kilometre intertidal wetlands investigated here have become much more prone to sedimentation than erosion. This phenomenon has also been well attested in coastal Germany and the Netherlands (p. 39, 45). Coastal wetlands are historically dynamic environments and, with the aid of archival maps, aerial photographs and satellite images, writes Verger, geographers can study the formation and withdrawal of schorre over long stretches of time. This geohistorical approach demonstrates that, depending on location, some schorres are advancing, some receding, while others are subject, simultaneously, to the action of erosion and sedimentation (p. 57).

Of great interest to human geographers, these phenomena, observed at the beginning of the Holocene Epoch and used to explain gradual sea-level rise as well as the relatively constant sedimentation and growth of intertidal marshes in France, resulted in the sequential dyking of French marshes from the Middle Ages until the 1970s. These physical and cultural phenomena are masterfully recorded by Verger and Ghirardi (p. 190-194 ; 258-265). Although this Nature-Culture relationship in coastal wetlands has been investigated by only a select few in North America, the physical and cultural processes leading to the appearance of new schorre – which consistently forms along the edges of newly dyked marshes like Mont Saint Michel and the Anse de l’Aiguillon – were used as reference models by geomorphologists, ecologists, conservationists and agricultural engineers in New England and Quebec in order to rationalize the feasibility and economic value of dyking coastal marshes.

In its conclusion, Zones humides du littoral français examines the shift in scientific and cultural attitudes toward wetlands since the 1960s. This coincided with the awakening of ecological consciousness and the recognition, first by hunters and ornithologists, and then by ecologists, of the immense value of coastal wetlands in their natural state. In the 1970s and 1980s, these shifts initiated a transition, still in progress: the unipolar productivist assessment of the value of coastal wetlands started to give way to a multipolar sustainable vision of their ecological, economic and social value. This conceptual shift is set to lead the management of France’s coastal wetlands into the 21^st century.