ABSTRACT
This article presents the results of atmospheric deposition from a 15-sites network which cover remote, agricultural, urban and industrial areas in the Iberian Peninsula and the Balearic Islands, with the aim of exploring geographical, climatic and natural vs anthropogenic gradients. Annual average fluxes of global deposition, discriminating insoluble (3,5-20,7â¯gâ¯m-2â¯year-1) and soluble-inorganic (7,1-45,5â¯gâ¯m-2â¯year-1) aerosols are discussed, seasonal patterns are regarded, and an attempt to estimate the impact of the main sources is presented. The wide range of atmospheric deposition fluxes (DF) regarding soluble (DFSOL) and insoluble (DFINS) has been investigated taking into consideration the contribution from nearby to long-distance sources, such as African dust, or regional-to-nearby ones, which include agricultural dust in the Ebro Valley, industrial emissions at different parts, urban dust at all cities, or saline dust resuspension from a dissicated lake bed. DFSOL is made up of marine aerosols, prevailing in coastal areas, with few exceptions in the Ebro Valley; nitrogen-species, homogeneously distributed across the network, with few exceptions due to agricultural sources; mineral dust, enhanced in the Ebro Valley owing to regional and agricultural emissions; and phospathe, displaying comparable values to other studies in general, but three hotspots at regional background environments have been identified. DFINS particles followed the aridity pattern, especially where anthropogenic emissions take place. Our estimates indicate that the regional dust to DFINS in the Ebro Valley represented 23-30%, overpassing 50% at intensive agricultural areas. Similarly, urban-metropolitan contributions accounted for 37-45% at the four cities, and 55% at the industrial one. African dust deposition was enhanced in the Central Pyrenees (75-80%) as a result of the magnification of atmospheric washout processes, and in south-eastern Iberia (69%) owing to the higher frequency of dust outbreaks.
ABSTRACT
We present a new locality with at least 880 vertebrate tracks found at the top of a limestone bed from the lower Miocene Tudela Formation (Spain). The trampled surface was formed by artiodactyls that crossed a muddy carbonate accumulated under the influence of water level variations in a palustrine environment. The tracks reflect different types of morphological preservation. The well-preserved tracks have tetradactyl digit impressions caused by both manus and pes, and are the type series of a new artiodactyl ichnotaxon, Fustinianapodus arriazui ichnogen. nov. and ichnosp. nov. The rest of the tracks, which are not as well preserved, are didactyl and were classified as undetermined artiodactyl tracks. According to their preservation, morphology, size, arrangement and orientation, we propose that this tracksite is the product of a social behaviour, particularly gregariousness, of a multi-age group of artiodactyls ~19 Ma ago. The morphologic and palaeoecologic data presented here suggest that the trackmakers were a group of anthracotheres with a livelihood similar to current hippos. They crossed, periodically, a fresh water palustrine area along some preferential pathways (trails).
