2014年1月2日 Nature ( {$ d% X4 l4 } 7 `& H! @2 a- _The deep-sea Hawaiian gold coral Kulamanamana haumeaae pictured in its living habitat during a NOAA/HURL Pisces V submersible dive. K. haumeaae is a remarkably long-lived species, sometimes attaining ages of thousands of years. Over the millennia these corals provide a unique geochemical time-series as they convert sinking phytoplankton and other tiny particles into a proteinaceous coral skeleton. Primary productivity in the North Pacific subtropical gyre has increased in recent decades despite a decline in nutrient supply. An ecosystem shift towards nitrogen-fixing plankton communities has been put forward as a possible explanation, but the cause for this shift remains unclear. Owen Sherwood and colleagues use nitrogen isotopic (δ15N) records from K. haumeaae corals to establish that the increase in nitrogen fixation had already began around 150 years ago, and that it may have been linked to Northern Hemisphere climate change since the end of the Little Ice Age. Cover image: NOAA Hawaii Undersea Research Laboratory, DSRV Pisces Pilot Max Cremer, 20049 c, Z8 V+ n% V) H
' ^7 C; G. h% r5 G: R1 q6 f1 Y6 U' D3 T0 c1 _- r: S' C 作者: 懵懂干细胞 时间: 2014-1-5 21:51
