There are various ways to assess the world's coastal ecosystems. The most pleasant would be to look at the idyllic and remarkable landscapes where land and sea meet. Yet one cannot ignore the consequences of unsustainable human development and activities in these fragile areas.
On a very small part of our oceans, these ecosystems, which come in a wide diversity of landscapes–wetlands, lagoons, estuaries, bays, or mangroves–represent nearly a third of both the ecological and economic resources of our planet. This richness, both qualitative and quantitative, is rooted in their interface. Of limited depth, subjected to physical constraints (wind, erosion, storms), nourished by the continental inputs, these heterogeneous ecosystems produce a wide biological diversity renewed by its close links to the sea. The diversity, accessibility, and richness of these privileged spaces have since the beginning of time attracted human populations. But the consequences of this long-standing migration pattern are becoming increasingly apparent: green and red tides, anoxia, invasive and toxic exotic species, extinct or endangered species, the disappearance of certain resources... These environments also undergo chronic and acute pollutions that leave the waters and living resources unsanitary and incompatible with human use. Climate change adds already perceptible threats to the overall integrity of these ecosystems.
Because they are naturally complex and diverse and subjected to a multitude of local and global constraints, it is imperative to conduct multidisciplinary research to understand how these ecosystems work and to anticipate their future sustainability. This research must be anchored on complementary approaches. The oldest one is observation. On the French coasts, observation is conducted under the auspices of CNRS' INSU (Institut National des Sciences de l'Univers) and the Ifremer surveillance networks. Assessing the evolution of the marine coastal ecosystems depends on the ongoing and improving technological characteristics of these networks.
Another essential approach is experimentation, which is required to understand the processes that govern diversity, interaction, and adaptation of these complex ecosystems and their components. National and international programs and institutions, including CNRS, through INSU and the Scientific Department of Environment and Sustainable Development, lend their support to understanding these changes, mostly caused by human activity. Such cooperation helps implement the much-needed federation of research communities and provides them with experimental platforms allowing to simulate anthropic forcing and to measure their effects.
Finally, computer modeling gives researchers a dynamic tool for integrating observational data, experimentation, and the coupling of given components and the related processes. This is an excellent means of establishing evolutionary scenarios for marine coastal ecosystems. These scenarios, by their content and objectives, must also be approached using an interdisciplinary cooperation between coastal oceanography and social and human sciences.
Observation, experimentation, and modeling, is the fundamental three-pronged approach not only for predicting and anticipating changes, but also for explaining and conserving the wealth of areas that are essential to humanity. And from this research, we should be able to construct a reasoned sustainable management strategy for the future.
1. Ecosystèmes lagunaires (CNRS / Université Montpellier II / Ifremer).
2. Ecosphère Continentale et Côtière.