Threats to the coastal zone
This article provides a review of human activities which put pressure on coastal ecosystems and habitats. It discusses generic modifications to coastal ecosystems in relation to specific human activities and introduces the various threats resulting from poorly managed activities.
Content
The sections of chapters can be accessed via the following links: Living resources
Biodiversity – Invasive species
Conclusion
Living organisms are an essential link in the turnover of biogeochemical cycles through costal systems. They are themselves vulnerable to rapid changes which take place in the coastal zone due to anthropogenic activities, but changes in the structure of populations of organisms will in turn affect the geochemistry of the habitat, to a point where such cycles might become dysfunctional. The consequences of such changes taking place in costal ecosystems may have consequences at global level leading to an unbalance in fluxes of energy and minerals at the interface between land and sea. The dynamics of such systems are very high and complex meaning that conservation is not just concerned with fixing the coast line to its physical actual limits, fighting erosion and sea-level rise. Because costal systems are alive, they are able to cope with changes of any sorts, but what counts is more the rate of change than the nature of the change. What makes the anthropocene unique is the rapidity of changes inflicted by humans to natural systems. Threats of all sorts from human activities onto ecosystems are now well documented but action remains difficult and uncertain because of a lack of understanding of the scale and of the speed of observed changes. Notably, the variability of natural systems is difficult to include in any political reasoning which relies on the certainty of statements for decision making. Through improving the scientific understanding of the performance of coastal ecosystems in terms of fluxes of energy and matter in relation to human impacts, integrated coastal management should become more able to predict the effects of measures taken and find adapted responses to fast evolving demands from society.
