quay enabling, by its colonization, the promotion of protection of concrete from chloride ions (gain on the aging of the structure which is avoided).
Figure 1.2. Eco-design project methodology (top blue arrow) compared to a standard approach (middle slice of the figure)12. For a color version of this figure, see www.iste.co.uk/pioch/marine.zip
We will therefore propose as a definition of eco-design of marine infrastructures the process of “designing sustainable maritime development projects with precise/specific technical and ecological functions13, which generate socioecosystemic co-benefits, without generating additional costs in the long term”.
It also seems important to us to address an aesthetic aspect for better integration into the underwater landscape. The aesthetic question of an object placed within a still “natural” environment, the seabed, seems essential to us. Indeed, addressing the “classic” needs of development meets precise rules of art, currently the subject of specifications, never integrating values of landscape aesthetics. However, the “beautiful” and “good” are always at the center of the concerns of humans, when they have the ambition to see their creations endure in the objective of being “well-made” and when they have the financial means to fully undertake this ambition. The morphologies of submerged elements are resolutely human and far from the soft forms usually found under the sea: cubes, trapezoids, beams, chaotic heaps, etc. A landscape approach would allow a better visual integration of these developments under the sea and undoubtedly a better acceptance of projects by the concerned actors and the general public. The contributions of bio-inspiration, more modest than the idea of biomimicry, can also usefully be called upon here, not only in terms of mechanisms that favor biodiversity (roughness, quality of materials, etc.), but also in terms of the overall visual aspect of a structure in a natural underwater environment. An eco-designed structure is a structure whose forms are bio-inspired and which integrates ecosystem conservation objectives into its functions, as well as its technical functions.
PIANC also emphasizes the need to design works according to the concept of sustainable development and publishes professional recommendations with this in mind (PIANC 2011a). This is the idea of “working with nature”, developed by Dorien Korbee, which is defined as:
an integrated process which involves working to identify and exploit win-win solutions which respect nature and are acceptable to both project proponents and environmental stakeholders. It is a philosophy which needs to be applied early in a project when flexibility is still possible (PIANC 2011b).
Nature-based solutions, popularized by the International Union for Conservation of Nature (IUCN), include infrastructure eco-design in their definition (Cohen-Shacham et al. 2016): “Nature-based solutions are actions built on ecosystems to address global challenges such as climate change or natural risk management”, for example, the biogenic seawall for coastline protection (Figure 1.3).
Figure 1.3. Diagram of the definition of nature-based solutions, proposed by the IUCN, where conventional infrastructure is cited as an application (Cohen-Shacham et al. 2016). For a color version of this figure, see www.iste.co.uk/pioch/marine.zip
Internationally, our definition of eco-design is related to the terms “green engineering”, “eco-engineering”, “nature-based solution” and “eco-design” (Pioch et al. 2018). It now seems interesting to us to better draw the spirit of this approach from the sources of inspiration of eco-design dedicated to marine environments, through the Japanese experience.
1.3. Japanese inspiration
It is in Japan, an archipelago country turned by necessity towards the sea, where the observation of nature is an art as much as a deep aspiration, that the ideas on the development of the seabed have been developed.
It was around the 17th century, during the reign of Emperor Jôo, that fish houses, reefs and artificial fishing habitats were built near the coast. It is within this culture of Sato-umi, literally “the sea where people live”, and this vision of a fertile and rich sea for those who know how to change it that the Japanese idea of eco-design was developed (Yanagi 2012).
The very root of the word œkodesign (oikos, from the Greek word for home or house) is completely in line with that of Sato-umi, based around the notions conveyed by ecumene14 and ecology. We can also find in this vision the inspiration developed by Rosenzweig and Michael (2003) for the ecology of reconciliation, where biodiversity and human development are closely intertwined in our “common home”.
1.3.1. Influence of the Japanese vision for sea-friendly development projects
François Doumenge15, in his book Le Japon et l’exploitation de la mer (1961), was impressed by “the incredible creativity of this people towards maritime productive development”. He emphasized the empirical and traditional approach of Asian societies, where the observation of nature, expressed in the Shinto spiritual tradition (or Kani-michi, the “voice of the gods”), gave a familiar closeness between humans and a deified nurturing nature, but in proximity, not in superiority (Doumenge 1961, 1966). In fact, the spirituality developed around nature and Shinto is more a way of life than a religion in the Western sense, according to Doumenge. This vision has also influenced Augustin Berque (1996). He admits in his reflections to having been inspired by the Japanese author Watsuji Tetsurō to clarify his vision of the ecumene where the human is intimately dependent on the natural environment. The sea (umi) is both a vital and respected environment because it is a place of intense spiritual activity where the kani (familiar deities) live and where the souls of the dead spend time. The Japanese view of the sea, and the underwater world, is also one that is comparable to our view of our earthly, poetic and scenic landscapes (Figure 1.4).
Moreover, the two basic principles of Japanese coastal maritime law (Amako 2015) are based on:
– the “Yoro Code” (養老律令 enacted in 757): “coastal areas are of common (public) use and are managed by the users themselves”;
– the “Ritsuryo Rules” (律令要約 enacted in 1741): “coastal areas are managed by delegation to local fishing communities”.
The management of natural marine environments closest to the activities carried out there, in this case fishing, is a marker structuring Japanese thinking.
Figure 1.4. Kushimoto Marine Park, protected for the value of underwater landscapes (photo: S. Pioch)
1.3.2. The Japanese Sato-umi
This particular view, and the predominance of the sea, is explained by the geography of Japan,
