The Shoreline between Nature and Society, a Changing Heritage - Vulnerability of Coastal Ecosystems and Adaptation - page 193

Figure 5.8. Green algae (Ulva lactuca) in Brittany, summer 2008. This type of
pollution is representative of the emergence of a form of agriculture that is closely
integrated within the industrial world (phosphate fertilizers and animal feed
sometimes obtained from industrial fishing). The different volumes indicate the
dissymmetry within Brittany with its short and steep rivers flowing into the Channel.
The algal bloom in spring and summer is occasioned by a disruption of the balance.
This constitutes a threat for biodiversity but is also difficult to resolve without
affecting social dynamics
5.3.5. The sediment deficit and the growing demand for sediments
with its effects on coastlines and the foreshore
The need for marine aggregates, silicates and calcareous sand (or
corals) in building industry, roads and for the refilling of beaches is
growing. This only gives rise to a few conflicts, but it presents itself as
a challenge for the future. In a similar way as States basing their
economy on oil and mining explore the continental margins, the sandy
resources are coveted by national authorities and private companies
that are aware of the difficulty in obtaining these resources. The
sources of sediments are first of all the continental shelves but as these
have been widely used and the regulations around extraction are as