Can We use a Landscape Approach to Assess Natural and Anthropogenic Perturbations of the Rocky Shore Ecosystems

Intertidal zone is a marine area which can be reached easily at low tide periods and consequently allows observation at the landscape scale, much larger than that of the subtidal zone. Then an intertidalscape approach can be developed, particularly on the rocky shores where a macroalgal and faunal zonation based on emersion rates help the understanding of structure and evolution of the ecosystem. In this paper, we give the baseline of a new approach of intertidalscape ecology from examples on the Brittany rocky shores and particularly by developing a visual index (Intertidalscape Boulder Field Index, IBFI) using the opportunistic behavior of the green macroalgae to characterize the hand-fishing impacts on the boulder field habitat of the low eulittoral zone, on the rocky shores of Brittany, France.