Table 3. Top-down calculations of mussel carbon budget for the mean expected harvest (ignoring seed stock) expressed as wet weight for two different trophic scenarios: years 1990, 2003. Values have been calculated by considering as a proxy the 1990 mussels physiological data, e.g., flesh dry weight % and carbon content. Globally, the carbon ingestion needed by mussels (F) is estimated as the sum of the carbon content of flesh dry weight (C, values from Brigolin et al. 2009), and the increase of carbon due to mean assimilation efficiency (D), both multiplied by the top-down trophic efficiency from mussels to phytoplankton (E, from Teramoto 1993, Townsend et al. 2000). In the lower part of the table the values of observed chlorophyll a converted to biomass (ratio Chl:C = 45) from year 2002 to year 2004 (simulation period) are reported to quantify the available biomass in each basin.