regions where phytoplankton growth is limited by the
availability of iron, additional iron supply from dust will
directly affect primary production and species composition (de Baar et al., 2005; Boyd et al., 2007). In oligotrophic regions limited and/or co-limited by nitrogen,
phosphorus, and iron availability, the impact of dust
(providing both P and Fe) will stimulate nitrogen fixation
organisms (Mills et al., 2004). Enrichment of dust in anthropogenic nitrogen (see above) can stimulate biological activity when the dust deposition relieves both P and
N limitation and co-limitation (Ridame et al., 2013). Toxic
elements such as Cu contained in transported dust can also
negatively impact phytoplankton (Paytan et al., 2009). Different phytoplankton groups show differential responses to
dust addition (e.g., Paytan et al., 2009; Giovagnetti et al.,
2013). Heterotrophic bacteria are stimulated also by dust
inputs in oligotrophic regions such as the Mediterranean
Sea (Pulido-Villena et al., 2008). The dominant response
(bacterial production vs. primary production) has been
shown to be dependent on the degree of oligotrophy, with
heterotrophic bacteria having a superior ability to take up
nutrients under ultraoligotrophic conditions (Marañón
et al., 2010). Such a competition for the additional nutrients
between heterotrophic bacteria and phytoplankton will
result in opposite effects on CO 2 drawdown, in particulate
organic carbon export, and thus on the carbon budget
(Marañón et al., 2010; Guieu et al., 2014).
Conclusions
Recent studies on the continental sources of dust aerosol
production, transport, and deposition in the ocean
increased the understanding of the importance of longrange transport of dust. The dust consists of fine (mostly
less than 2 mm) particles originating mainly in the arid
tropical and subtropical regions extending into the oceans
and is similar in composition to deep-sea (pelagic) red
clays. The total contribution of dust sedimentation is
almost equal to the net influx of the riverine terrigenous
material to the pelagic zones of the ocean (Windom,
1975; Lisitzin, 2011). By bringing to the ocean surface
iron and other essential nutrients, dust creates an impact
on the ocean’s biogeochemistry, affecting carbon fixation,
respiration, and nitrogen fixation, depending on the ongoing limitation and co-limitation where the deposition
occurs (Moore et al., 2013). A number of important issues,
relevant to the International Surface Ocean-Lower Atmosphere Study (SOLAS) research community, have
recently been raised to better link atmospheric deposition
of nutrients, ocean productivity, and feedbacks to climate
(Law et al., 2013). In this complex picture, dust is nodal,
in particular because of the dominant role of strong-pulse
events in atmospheric deposition (Guieu et al., 2014).
A better understanding of these links is crucial to accurately represent the present role of atmospheric deposition
of new nutrients and particles in marine biogeochemical
models and to be able to predict its evolution in a context
of global and anthropogenic changes.
Bibliography
Andreae, M. O., and Rosenfeld, D., 2008. Aerosol-cloudprecipitation interactions. Part 1. The nature and sources of
cloud-active aerosols. Earth-Science Reviews, 89, 13–41.
Baker, A. R., and Croot, P. L., 2010. Atmospheric and marine controls on aerosol iron solubility in seawater. Marine Chemistry,
120, 4–13.
Boyd, P. W., Jickells, T., Law, C. S., Blain, S., et al., 2007.
A synthesis of mesoscale iron-enrichment experiments
1993–2005: key findings and implications for ocean biogeochemistry. Science, 315, 612–617.
Bressac, M., and Guieu, C., 2013. Post-depositional processes: what
really happens to new atmospheric iron in the ocean surface?
Global Biogeochemical Cycles, 27, 859–870, doi:10.1002/
gbc.20076.
Bressac, M., et al., 2011. A mesocosm experiment coupled with
optical measurements to observe the fate and sinking of atmospheric particles in clear oligotrophic waters. Geo-Marine Letters, doi:10.1007/s00367-011-0269-4.
Brust, J., and Waniek, J. J., 2010. Atmospheric dust contribution to
deep-sea particle fluxes in the subtropical Northeast
Atlantic. Deep-Sea Research Part I, 57, 988–998.
Chavagnac, V., Lair, V., Milton, J. A., Lloyd, A., Croudace, I. W.,
Palmer, M. R., Green, D. R. H., and Cherkashev, G. A., 2008.
Tracing dust input to the Mid-Atlantic Ridge between 14
45
0 N
and 36
14
0 N: geochemical and Sr isotope study. Marine Geology, 247, 208–225.
Chin, M., Diehl, T., Ginoux, P., and Malm, W., 2007. Intercontinental transport of pollution and dust aerosols: implications for
regional air quality. Atmospheric Chemistry and Physics, 7,
5501–5517.
de Baar, H. J. W., Boyd, P. W., Coale, K. H., Landry, M. R., Tsuda,
A., Assmy, P., Bakker, D. C. E., Bozec, Y., Barber, R. T.,
Brzezinski, M. A., Buesseler, K. O., Boyé, M. P., Croot, L.,
Gervais, F., Gorbunov, M. Y., Harrison, P. J., Hiscock, W. T.,
Laan, P., Lancelot, C., Law, C. S., Levasseur, M., Marchetti,
A., Millero, F. J., Nishioka, J., Nojiri, Y., van Oijen, T., Riebesell,
U., Rijkenberg, M. J. A., Saito, H., Takeda, S., Timmermans,
K. R. T., Veldhuis, M. J. W., Waite, A. M., and Wong, C.-S.,
2005. Synthesis of iron fertilization experiments: from the iron
age in the age of enlightenment. Journal of Geophysical
Research, 110, C09S16, doi:10.1029/2004JC002601.
de Leeuw, G., Guieu, C., Arneth, A., Bellouin, N., Bopp, L., Boyd,
P. W., Denier van der Gon, H. A. C., Desboeufs, K. V., Dulac, F.,
Facchini, M. C., Gantt, B., Langmann, B., Mahowald, N. M.,
Marañon, E., O’Dowd, C., Olgun, N., Pulido-Villena, E.,
Rinaldi, M., Stephanou, E. G., and Wagener, T., 2014. Ocean–
atmosphere interactions of particles. In Liss, P. S., and Johnson,
M. T. (eds.), Ocean–Atmosphere Interactions of Gases and Particles. Heidelberg: Springer, pp. 171–246.
Fisher, D. A., 1979. Comparison of 105 years of oxygen isotope and
insoluble impurity profiles from the Devon Island and Camp
Century ice cores. Quaternary Research, 11, 299–305.
Geng, H., Park, Y., Hwang, H., Kang, S., and Ro, C. U., 2009. Elevated nitrogen-containing particles observed in Asian dust aerosol samples collected at the marine boundary layer of the Bohai
Sea and the Yellow Sea. Atmospheric Chemistry and Physics, 9,
6933–6947.
Ginoux, P., Chin, M., Tegen, I., Prospero, J. M., Holben, B.,
Dubovik, O., and Lin, S.-J., 2001. Sources and distributions of
dust aerosols simulated with the GOCART model. Journal of
Geophysical Research, 106, 20255–20273.
Giovagnetti, V., Brunet, C., Conversano, F., Tramontano, F.,
Obernosterer, I., Ridame, C., and Guieu, C., 2013. Assessing
the role of dust deposition on phytoplankton ecophysiology
and succession in a low-nutrient low-chlorophyll ecosystem: a
206
DUST IN THE OCEAN
availability of iron, additional iron supply from dust will
directly affect primary production and species composition (de Baar et al., 2005; Boyd et al., 2007). In oligotrophic regions limited and/or co-limited by nitrogen,
phosphorus, and iron availability, the impact of dust
(providing both P and Fe) will stimulate nitrogen fixation
organisms (Mills et al., 2004). Enrichment of dust in anthropogenic nitrogen (see above) can stimulate biological activity when the dust deposition relieves both P and
N limitation and co-limitation (Ridame et al., 2013). Toxic
elements such as Cu contained in transported dust can also
negatively impact phytoplankton (Paytan et al., 2009). Different phytoplankton groups show differential responses to
dust addition (e.g., Paytan et al., 2009; Giovagnetti et al.,
2013). Heterotrophic bacteria are stimulated also by dust
inputs in oligotrophic regions such as the Mediterranean
Sea (Pulido-Villena et al., 2008). The dominant response
(bacterial production vs. primary production) has been
shown to be dependent on the degree of oligotrophy, with
heterotrophic bacteria having a superior ability to take up
nutrients under ultraoligotrophic conditions (Marañón
et al., 2010). Such a competition for the additional nutrients
between heterotrophic bacteria and phytoplankton will
result in opposite effects on CO 2 drawdown, in particulate
organic carbon export, and thus on the carbon budget
(Marañón et al., 2010; Guieu et al., 2014).
Conclusions
Recent studies on the continental sources of dust aerosol
production, transport, and deposition in the ocean
increased the understanding of the importance of longrange transport of dust. The dust consists of fine (mostly
less than 2 mm) particles originating mainly in the arid
tropical and subtropical regions extending into the oceans
and is similar in composition to deep-sea (pelagic) red
clays. The total contribution of dust sedimentation is
almost equal to the net influx of the riverine terrigenous
material to the pelagic zones of the ocean (Windom,
1975; Lisitzin, 2011). By bringing to the ocean surface
iron and other essential nutrients, dust creates an impact
on the ocean’s biogeochemistry, affecting carbon fixation,
respiration, and nitrogen fixation, depending on the ongoing limitation and co-limitation where the deposition
occurs (Moore et al., 2013). A number of important issues,
relevant to the International Surface Ocean-Lower Atmosphere Study (SOLAS) research community, have
recently been raised to better link atmospheric deposition
of nutrients, ocean productivity, and feedbacks to climate
(Law et al., 2013). In this complex picture, dust is nodal,
in particular because of the dominant role of strong-pulse
events in atmospheric deposition (Guieu et al., 2014).
A better understanding of these links is crucial to accurately represent the present role of atmospheric deposition
of new nutrients and particles in marine biogeochemical
models and to be able to predict its evolution in a context
of global and anthropogenic changes.
Bibliography
Andreae, M. O., and Rosenfeld, D., 2008. Aerosol-cloudprecipitation interactions. Part 1. The nature and sources of
cloud-active aerosols. Earth-Science Reviews, 89, 13–41.
Baker, A. R., and Croot, P. L., 2010. Atmospheric and marine controls on aerosol iron solubility in seawater. Marine Chemistry,
120, 4–13.
Boyd, P. W., Jickells, T., Law, C. S., Blain, S., et al., 2007.
A synthesis of mesoscale iron-enrichment experiments
1993–2005: key findings and implications for ocean biogeochemistry. Science, 315, 612–617.
Bressac, M., and Guieu, C., 2013. Post-depositional processes: what
really happens to new atmospheric iron in the ocean surface?
Global Biogeochemical Cycles, 27, 859–870, doi:10.1002/
gbc.20076.
Bressac, M., et al., 2011. A mesocosm experiment coupled with
optical measurements to observe the fate and sinking of atmospheric particles in clear oligotrophic waters. Geo-Marine Letters, doi:10.1007/s00367-011-0269-4.
Brust, J., and Waniek, J. J., 2010. Atmospheric dust contribution to
deep-sea particle fluxes in the subtropical Northeast
Atlantic. Deep-Sea Research Part I, 57, 988–998.
Chavagnac, V., Lair, V., Milton, J. A., Lloyd, A., Croudace, I. W.,
Palmer, M. R., Green, D. R. H., and Cherkashev, G. A., 2008.
Tracing dust input to the Mid-Atlantic Ridge between 14
45
0 N
and 36
14
0 N: geochemical and Sr isotope study. Marine Geology, 247, 208–225.
Chin, M., Diehl, T., Ginoux, P., and Malm, W., 2007. Intercontinental transport of pollution and dust aerosols: implications for
regional air quality. Atmospheric Chemistry and Physics, 7,
5501–5517.
de Baar, H. J. W., Boyd, P. W., Coale, K. H., Landry, M. R., Tsuda,
A., Assmy, P., Bakker, D. C. E., Bozec, Y., Barber, R. T.,
Brzezinski, M. A., Buesseler, K. O., Boyé, M. P., Croot, L.,
Gervais, F., Gorbunov, M. Y., Harrison, P. J., Hiscock, W. T.,
Laan, P., Lancelot, C., Law, C. S., Levasseur, M., Marchetti,
A., Millero, F. J., Nishioka, J., Nojiri, Y., van Oijen, T., Riebesell,
U., Rijkenberg, M. J. A., Saito, H., Takeda, S., Timmermans,
K. R. T., Veldhuis, M. J. W., Waite, A. M., and Wong, C.-S.,
2005. Synthesis of iron fertilization experiments: from the iron
age in the age of enlightenment. Journal of Geophysical
Research, 110, C09S16, doi:10.1029/2004JC002601.
de Leeuw, G., Guieu, C., Arneth, A., Bellouin, N., Bopp, L., Boyd,
P. W., Denier van der Gon, H. A. C., Desboeufs, K. V., Dulac, F.,
Facchini, M. C., Gantt, B., Langmann, B., Mahowald, N. M.,
Marañon, E., O’Dowd, C., Olgun, N., Pulido-Villena, E.,
Rinaldi, M., Stephanou, E. G., and Wagener, T., 2014. Ocean–
atmosphere interactions of particles. In Liss, P. S., and Johnson,
M. T. (eds.), Ocean–Atmosphere Interactions of Gases and Particles. Heidelberg: Springer, pp. 171–246.
Fisher, D. A., 1979. Comparison of 105 years of oxygen isotope and
insoluble impurity profiles from the Devon Island and Camp
Century ice cores. Quaternary Research, 11, 299–305.
Geng, H., Park, Y., Hwang, H., Kang, S., and Ro, C. U., 2009. Elevated nitrogen-containing particles observed in Asian dust aerosol samples collected at the marine boundary layer of the Bohai
Sea and the Yellow Sea. Atmospheric Chemistry and Physics, 9,
6933–6947.
Ginoux, P., Chin, M., Tegen, I., Prospero, J. M., Holben, B.,
Dubovik, O., and Lin, S.-J., 2001. Sources and distributions of
dust aerosols simulated with the GOCART model. Journal of
Geophysical Research, 106, 20255–20273.
Giovagnetti, V., Brunet, C., Conversano, F., Tramontano, F.,
Obernosterer, I., Ridame, C., and Guieu, C., 2013. Assessing
the role of dust deposition on phytoplankton ecophysiology
and succession in a low-nutrient low-chlorophyll ecosystem: a
206
DUST IN THE OCEAN