Saturacion del carbonato de calcio en un area de cultivo de mitilidos en el Seno Reloncavi, Patagonia norte, Chile

Abstract

The surface waters temperature, salinity, total alkalinity and dissolved inorganic carbon were measured within an area dedicated to the industrial production of Chilean mussel at Reloncavi Sound Northern Patagonian during Austral autumn (May 2012) and Austral summer 2013 (January). We calculate that the calcium carbonate saturation state (ΩCaCO3) of surface waters within the study area was low (ΩAr <2) and even “corrosive” surface seawater for CaCO 3 ( i.e ., subsaturated water, Ω <1) when waters of low salinity (<28) and total alkalinity (< 1800 µmol kg -1 ) were advected to the production center during May 2012. In January 2013 the low salinity (<25) water were associated to low total alkalinity ( ca . 1700 µmol kg -1 ) which are produce low ΩAr in surface water fully equilibrated with the atmosphere ( i.e ., 400 µatm). So we suggest here that events of low and even “corrosive” waters for CaCO 3 in these centers of production of Chilean mussel at Northern Patagonian may be a frequent condition. The recent report of the potential decrement in the Chilean mussel ( Mytilus chilensis ) productivity due to ocean acidification (Navarro et al ., 2013) and the occurrence of CaCO 3 corrosive waters reported here, depict the pertinence of including the carbonate system as a key variable in the assessment of the “carrying capacity” of this coastal systems.