Increasing frequency of Saharan rains over northeastern Spain and its ecological consequences

Desert areas in North Africa are important sources of mineral dust to the atmosphere, which upon deposition can influence oceanic and terrestrial biogeochemical cycles and affect forest productivity. Here, an increase of the frequency of rainfall loaded with such dust (red rain) in the last decades is documented for a site in northeastern Spain. The relevance of such a trend for the neutralization of acid rain and the delivery of nutrients in significant amounts to Mediterranean ecosystems is described. (C) 1999 Elsevier Science B.V. All rights reserved.