Ocean's Ability to fix Nitrogen Underestimated
In order to predict how Earth's climate develops scientists have to know which gases and trace elements are naturally bound and released by the ocean and in which quantities. For nitrogen, an essential element for the production of biomass, there are many unanswered questions. Scientists from Kiel, Bremen and Halifax have now published a research study in the international journal Nature showing that widely applied methods are part of the problem.
Of course scientists like it when the results of measurements fit with each other. However, when they carry out measurements in nature and compare their values, the results are rarely "smooth." A contemporary example is the ocean's nitrogen budget. Here, the question is: how much nitrogen is being fixed in the ocean and how much is released? "The answer to this question is important to predicting future climate development. All organisms need fixed nitrogen in order to build genetic material and biomass," explains Professor Julie LaRoche from the GEOMAR | Helmholtz Centre for Ocean Research Kiel.
Despite scientific efforts, the nitrogen budget suffers from an apparent dilemma. The analysis of ocean sediment as a long-term climate archive has shown that the amounts of fixed nitrogen equaled those of released nitrogen for the past 3000 years. However, modern measurements in the ocean demonstrate that the amounts of released nitrogen exceed the amounts of nitrogen being fixed. These results leave a "gap" in the nitrogen budget and show inconsistencies between past, long-term reconstruction and short-term measurements.
In 2010, the GEOMAR microbiologist Wiebke Mohr pointed out that these inconsistencies could be partially due to the methods widely used to measure modern biological nitrogen fixation. Following this finding, scientists from GEOMAR, Christian-Albrechts-University of Kiel (CAU), Max Planck Institute for Marine Microbiology (MPI) Bremen and Dalhousie University in Halifax (Canada) tested a new approach in the Atlantic Ocean which had been suggested by Mohr: The results of the study are now presented in the international journal "Nature."
Storm over ocean photo via Shutterstock.
Read more at ScienceDaily.