Abstract. The importance of particulate organic carbon and phosphorus (P) delivered from shelves on open ocean productivity, oxygen, and reactive P burial during glacial times has been assessed using a biogeochemical ocean model of the carbon (C), P and iron cycles. The model shows that in simulations of the Last Glacial Maximum (LGM) without any inputs of terrigenous material from shelves there is a moderate increase in productivity (+5 %) and mean deep water oxygen (+29 %) relative to the preindustrial simulation. However, when the input of terrigenous particulate organic C and P is considered as an additional forcing in the LGM simulation, ocean productivity increases by 46 %, mean deep water oxygen concentration decreases by 20 %, and the global rate of reactive P burial is 3 times over the preindustrial value. The associated pattern of negative oxygen anomalies at 1000 m induces a deepening of the Atlantic and Indian Ocean oxygen minimum (OMZ), while in the Pacific Ocean the OMZ is shifted to the eastern basin north of the Equator relative to preindustrial times. In addition, negative trends in oxygen extend globally below 2000 m depth, though their magnitude is rather weak, and in particular bottom waters remain above suboxic levels. Changes in dust deposition can be responsible for positive trends in reactive P burial as simulated at the LGM in open ocean regions, notably over the Southwest Atlantic and Northwest Pacific; on the other hand, inputs of terrigenous material from shelves cause an increase in P burial over the continental slope and rise regions which accounts for 47 % of the total reactive P burial change. Although the glacial-interglacial trends in P burial in our model compare well with the available observations, this study highlights the need of much more core records of C and P in open ocean settings.
Zoidbergus, A New Genus of Apseudidae (Tanaidacea) with Remarks on Apseudes Siegi and Apseudes Vitjazi