Iron biogeochemistry across marine systems – progress from the past decade

Biogeosciences (Impact Factor: 3.98). 03/2010; DOI: 10.5194/bg-7-1075-2010
Source: DOAJ


Based on an international workshop (Gothenburg, 14–16 May 2008), this review article aims to combine interdisciplinary knowledge from coastal and open ocean research on iron biogeochemistry. The major scientific findings of the past decade are structured into sections on natural and artificial iron fertilization, iron inputs into coastal and estuarine systems, colloidal iron and organic matter, and biological processes. Potential effects of global climate change, particularly ocean acidification, on iron biogeochemistry are discussed. The findings are synthesized into recommendations for future research areas.

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Available from: Martha Gledhill
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    • "During the 2010–2011 exploration season of the E/V Nautilus we studied the deep benthic environment of the Levantine basin, the most oligotrophic part of the Mediterranean Sea [23]. The contrast between the high iron demand for required for nitrogen fixation [24] and the low iron availability in the surface waters [25] may explain the low nitrogen fixation rates in this area [26]. The paradigm of Fe-rich dust supply to surface waters as the dominant iron source includes Levantine basin [27]. "
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    • "Iron limitation controls biological productivity in 30 % of the world's oceans (Ardelan and Steinnes 2010); therefore, assessing the potential effects of OA on iron biogeochemistry is crucial. Millero et al. (2009) showed that a decrease in pH from 8.1 to 7.4 will increase the solubility of Fe(III) by approximately 40 %, whilst Breitbarth et al. (2010) showed a similar pH decrease could cause a 10-fold increase in the half-life of Fe(II). In comparison, other studies have suggested that the bioavailability of iron will decrease under acidified conditions (Martin and Fitzwater 1988; Shi et al. 2010). "
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    • "In addition, terrestrially derived humic substances apparently play a major role as chelators for iron and other trace metals (Laglera and van den Berg 2009) in the marine environment. This holds true especially for high nutrient low chlorophyll (HNLC) areas where iron limits primary production (Breitbarth et al. 2010). The Tanner Moor, a pristine submountainous raised peat bog in Lower Austria, releases water with elevated NOM and iron content (Krachler et al. 2005). "
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