A roadmap to knowledge-based maritime spatial planning.

The Cells of Ecosystem Functioning are natural units of management and conservation, allowing for an ecosystem-based maritime spatial planning based on an accurate knowledge of marine biodiversity and ecosystem functioning which, however, is presently insufficient and fragmentary. A five-step roadmap to fill current knowledge gaps and make ecosystem-based marine sustainability possible is proposed: Step 1: make the inventory of biodiversity. Step 2: unveil the roles of species. Step 3: understand the ecological relationships that link species with each other and with the physical environment. Step 4: frame marine biodiversity and ecosystem functioning in a five dimensional spatial and temporal context (the Cells of Ecosystem Functioning). Step 5: plan our activities so as to preserve a healthy state of ecosystems. EU legislation has drawn a careful map to guide us along this road, with a series of directives that, if successfully enforced, will be conducive to knowledge-based marine sustainability.