Conditions required for oceanic anoxia/euxinia: Constraints from a one-dimensional ocean biogeochemical cycle model

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

Widespread black shale depositional intervals termed oceanic anoxic events (OAEs) occurred repeatedly during the Phanerozoic Eon. Here we developed a new vertical one-dimensional ocean biogeochemical cycle model that involves several chemical reactions in an oxic-anoxic-sulfidic water column. To explore the theoretical constraints for global oceanic anoxia/euxinia quantitatively and systematically, we conducted sensitivity analyses of the proposed causal mechanisms, including elevated rates of riverine phosphorus (P) input, ocean stagnation, and lowered oxygen solubility due to climate warming. We gave special attention to the vertical chemical structure of the ocean and also to the characteristic behaviors of the marine P cycle under anoxic conditions, because the relationship between the depth of anoxia and the benthic phosphorus flux could be important for the occurrence of oceanic anoxia/euxinia. Steady-state simulations indicated that (1) a decrease in ocean stagnation or oxygen solubility is not enough by itself to achieve widespread anoxia with the present reactive P river input rate, and (2) shallow water anoxia followed by massive P liberation from surface sediments can lead to widespread eutrophication and anoxia/euxinia. We conclude that elevated riverine flux of reactive P is the most important factor for triggering global anoxic events via a positive feedback loop among ocean anoxia, phosphorus regeneration, and surface biological productivity.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Conditions required for oceanic anoxia/euxinia: Constraints from a one-dimensional ocean biogeochemical cycle model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Conditions required for oceanic anoxia/euxinia: Constraints from a one-dimensional ocean biogeochemical cycle model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Conditions required for oceanic anoxia/euxinia: Constraints from a one-dimensional ocean biogeochemical cycle model will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-764364

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.