Atmospheric acidification of mineral aerosols: a source of bioavailable phosphorus for the oceans 1School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
01 Jul 2011
2School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
3Institute of Chemical Engineering and High Temperature Chemical Processes, Foundation for Research and Technology Hellas, Patras, Greece
4Earth and Biosphere Institute, School of Earth and Environment, University of Leeds, Leeds, UK
5Department of Chemistry, University of Crete, Heraklion, Crete, Greece
6Israel Oceanographic Limnological Research, Tel Shikmona, Haifa, Israel
Received: 11 Feb 2011 – Published in Atmos. Chem. Phys. Discuss.: 21 Feb 2011 Abstract. Primary productivity of continental and marine ecosystems is often
limited or co-limited by phosphorus. Deposition of atmospheric aerosols
provides the major external source of phosphorus to marine surface waters.
However, only a fraction of deposited aerosol phosphorus is water soluble
and available for uptake by phytoplankton. We propose that atmospheric
acidification of aerosols is a prime mechanism producing soluble phosphorus
from soil-derived minerals. Acid mobilization is expected to be pronounced
where polluted and dust-laden air masses mix. Our hypothesis is supported by
the soluble compositions and reconstructed pH values for atmospheric
particulate matter samples collected over a 5-yr period at Finokalia,
Crete. In addition, at least tenfold increase in soluble phosphorus was
observed when Saharan soil and dust were acidified in laboratory experiments
which simulate atmospheric conditions. Aerosol acidification links
bioavailable phosphorus supply to anthropogenic and natural acidic gas
emissions, and may be a key regulator of ocean biogeochemistry.
Revised: 14 May 2011 – Accepted: 27 May 2011 – Published: 01 Jul 2011
Citation: Nenes, A., Krom, M. D., Mihalopoulos, N., Van Cappellen, P., Shi, Z., Bougiatioti, A., Zarmpas, P., and Herut, B.: Atmospheric acidification of mineral aerosols: a source of bioavailable phosphorus for the oceans, Atmos. Chem. Phys., 11, 6265-6272, doi:10.5194/acp-11-6265-2011, 2011.