the effects of natural iron fertilisation on deep-sea ecology the crozet plateau, southern indian ocean自然铁受精的影响深海生态学海克罗泽高原,南部印度洋.pdf

The Effects of Natural Iron Fertilisation on Deep-Sea Ecology: The Crozet Plateau, Southern Indian Ocean 1 2 2 1 2¤a George A. Wolff *, David S. M. Billett *, Brian J. Bett , Jens Holtvoeth , Tania FitzGeorge-Balfour , 1 2 2 2¤b 2 3 Elizabeth H. Fisher , Ian Cross , Roger Shannon , Ian Salter , Ben Boorman , Nicola J. King , Alan 3 ´ ´ 1 Jamieson , Frederic Chaillan 1 School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom, 2 National Oceanography Centre, University of Southampton Waterfront Campus, Southampton, United Kingdom, 3 Oceanlab, University of Aberdeen, Newburgh, United Kingdom Abstract The addition of iron to high-nutrient low-chlorophyll (HNLC) oceanic waters stimulates phytoplankton, leading to greater primary production. Large-scale artificial ocean iron fertilization (OIF) has been proposed as a means of mitigating anthropogenic atmospheric CO2, but its impacts on ocean ecosystems below the photic zone are unknown. Natural OIF, through the addition of iron leached from volcanic islands, has been shown to enhance primary productivity and carbon export and so can be used to study the effects of OIF on life in the ocean. We compared two closely-located deep-sea sites (,400 km apart and both at ,4200 m water depth) to the East (naturally iron fertilized; +Fe) and South (HNLC) of the Crozet Islands in the southern Indian Ocean. Our results suggest that long-term geo-engineering of surface oceanic wat