Kalender

Dear all, 

This Thursday (26th September) at 10:15, there will be a BCCR seminar by Anders Stigebrandt on “Sea-based measures to improve the oxygen conditions in stagnant sea basins – experience from previous oxygenation of the Swedish By Fjord and thoughts about the application of possible future measures”.

The seminar will take place in the Bjerknes lecture room (4th floor, room 4020). For those not able to attend in person, it will be possible to join on zoom.

Abstract

From a general equation for the minimum concentration of dissolved oxygen (DO) in periodically stagnant basins, five different sea-based measures to improve the minimum oxygen concentration are discussed. The application of sea-based measures might be particularly interesting in basins that have poor oxygen conditions despite land-based measures are fully implemented. Sea-based measures might also be considered to compensate for increased oxygen consumption due to e.g. fish farming in open cages or to improve the habitat in basins with naturally poor oxygen conditions.

The basin water of the By Fjord at Uddevalla, Sweden was oxygenated 2010 – 2012 during a pilot experiment (BOX). The goal was to learn how to oxygenate the anoxic deepwater in the Baltic Sea to get rid of the eutrophication that is driven by phosphorus leakage from anoxic bottoms. Recently citizens in Uddevalla took the initiative to oxygenate the fjord permanently to create a permanent good habitat for cod and other animals. Initially they use the same measure as the BOX project, pumping less salt and well oxygenated surface water into the saltier basin water. However, in future other measures involving the use of green oxygen, produced as a byproduct from green hydrogen production by hydrolysis of water, may be considered.