Statistical calibration of the Carlit index in the Pontine Island of Zannone

The WFD, adopted by the European Community requires that Member States achieve and maintain a good ecological status of all water bodies by 2015. In the marine context, the ecological status has to be quantied applying indexes based on appropriate key biological elements. The CARLIT index is a car- tographic monitoring tool enabling the EQR2 to be calculated using macroalgae in coastal hard bottoms as a key biological element. Here we investigate the role of Cystoseira amentacea var.stricta: a key macroalgae involved in the index denition. We analyze the relation between the algae presence and geomorphological character- istics of Pontine Islands coast through standard logistic regression and autologistc models to account for spatial correlation