Perspective: continental inputs of matter into planktonic ecosystems of Argentinean continental shelf - the case of atmospheric dust

CRESPI-ABRIL, AUGUSTO; BARBIERI, E.S.; GRACIA-VILLALOBOS, LEILÉN; SORIA, RODRIGO GASPAR; PAPARAZZO, FLAVIO; PACZKOWSKA, JOANNA; GONÇALVES, R.J.

Plankton Ecology of the Southwestern Atlantic - From the subtropical to the subantarctic realm

Springer

Año: 2018;

Land-derived dissolved andparticulate matter (allochthonous matter) affect pelagic ecosystems by changingfactors which include light penetration, nutrient availability, substrateconcentration and, in general, biogeochemical cycles in the ocean. In a contextof increasing anthropogenic impact, this material may not only increase itsload but also carry toxic substances. Riverine runoff is the most studiedmechanism of particulate matter input from the continent to the shelf in thesouthern region of South America where the continental shelf is widest (e.g.,Atlantic Patagonia). However, there are other sources of particulate matterwhich are not affected by rivers in this semi-arid region: aeolian material.Winds in this region (notably the South Hemisphere Westerlies) are the only waycontinental aeolian material (atmospheric aerosols or ?dust?) can reach notonly the shelf but even further onto oceanic HNLC (High Nutrients- LowChlorophyll) waters of the Atlantic Southern Ocean. This potential impact ofPatagonian dust beyond the continental shelf attracts attention to the globalclimate community, and at the same time it opens questions about the potentialeffects of dust in coastal waters. According to previous work and ongoing studies,deposited particles can have significant impacts in the chemical and biologicalcomponents in the euphotic zone. However the effects of this airborne materialin plankton ecosystems of South America is largely unknown, mostly due to lackof in situ studies and observations. Since the events of dustmobilization, transport and deposition are expected to increase (due to climatechange) and interact with other global change factors such as warming and moreintensive land use, the influence of dust input may become more prominent forcoastal and oceanic regions of southern South America in the next decades.