On the difficulty of estimating dust deposition effects in the Mediterranean at ecological time scales

Aquatic Sciences Meeting, Aquatic Sciences: Global And Regional Perspectives - North Meets South, 22-27 February 2015, Granada, SpainThe surface Mediterranean is one of the most oligotrophic seas in the world. Chlorophyll and primary production tend to be very low and limited by inorganic nutrients. At the same time the Mediterranean basin receives a large amount of nutrients through aerosol deposition from its surrounding arid areas, especially from the Saharan desert, the main source area of mineral dust in the world. This has important consequences for the biogeochemical budget of the basin over geological time scales. At ecological time scales, the relative input of atmospheric nutrients is small for a given time and area. Hence, the effects of such inputs are difficult to detect. We have both extensively analyzed correlations between ocean chlorophyll and modeled Saharan dust deposition at the Mediterranean basin scale and done a battery of aerosol amendment experiments in order to elucidate the role of atmospheric deposition at ecological time scales. Albeit effects in the water column are small, they can be detected with statistical significance under certain conditions and are transmitted through the food webPeer Reviewe