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Helgol Mar Res (2014) 68:253262 DOI 10.1007/s10152-014-0385-4
ORIGINAL ARTICLE
Sponge bioerosion accelerated by ocean acidication across species and latitudes?
M. Wisshak C. H. L. Schnberg A. Form
A. Freiwald
Received: 19 July 2013 / Revised: 24 January 2014 / Accepted: 10 February 2014 / Published online: 25 February 2014 Springer-Verlag Berlin Heidelberg and AWI 2014
Abstract In many marine biogeographic realms, bioeroding sponges dominate the internal bioerosion of calcareous substrates such as mollusc beds and coral reef framework. They biochemically dissolve part of the carbonate and liberate so-called sponge chips, a process that is expected to be facilitated and accelerated in a more acidic environment inherent to the present global change. The bioerosion capacity of the demosponge Cliona celata Grant, 1826 in subfossil oyster shells was assessed via alkalinity anomaly technique based on 4 days of experimental exposure to three different levels of carbon dioxide partial pressure (pCO2) at ambient temperature in the cold-temperate waters of Helgoland Island, North Sea. The rate of chemical bioerosion at present-day pCO2 was quantied with 0.080.1 kg m-2 year-1. Chemical bioerosion was positively correlated with increasing pCO2, with rates more than doubling at carbon dioxide levels predicted for the end of the twenty-rst century, clearly conrming that C. celata bioerosion can be expected to be enhanced with
progressing ocean acidication (OA). Together with previously published experimental evidence, the present results suggest that OA accelerates sponge bioerosion (1) across latitudes and biogeographic areas, (2) independent of sponge growth form, and (3) for species with or without photosymbionts alike. A general increase in sponge bioerosion with advancing OA can be expected to have a signicant impact on global carbonate (re)cycling and may result in widespread negative effects, e.g. on the stability of wild and farmed shellsh populations, as well as calcareous framework builders in tropical and cold-water coral reef ecosystems.
Keywords Ocean acidication Bioerosion Bioeroding
sponges Cliona celata Helgoland North Sea
Introduction
Degradation of calcareous materials by marine bioerosion is an important recycling process that acts at different scales and is performed by a wide spectrum of organisms employing different chemical and mechanical means in the process of attachment, grazing, or carbonate penetration (Warme 1975; Bromley 1992; Wisshak and Tapanila 2008; Tribollet et al. 2011; Wisshak 2012). Considering the signicant environmental...