English (United Kingdom)
Home Abstracts Importance of Gas Solubility Coefficients as a Function of Temperature and Salinity for Use in Nitro

Drucken E-Mail

• Importance of Gas Solubility Coefficients as a Function of Temperature and Salinity for Use in Nitrogen Fixation Assays

E. Breitbarth, M.M. Mills, G. Friedrichs, and J. LaRoche
Limnol. and Oceanog.: Methods 2 (2004) 282-288

 

The acetylene reduction assay is a common method for assessing nitrogen fixation in a variety of marine and freshwater systems. The method measures ethylene, the product of the conversion of the gas acetylene to its reduced form by nitrogenase. Knowledge of the solubility of ethylene in aqueous solution is crucial to the calculation of nitrogen fixation rates and depends on the temperature and salinity of the assay conditions. Despite the increasing interest in marine nitrogen fixation, no gas solubility (Bunsen) coefficients for ethylene in seawater are published to date. Here, we provide a set of equations and present semi-empirically derived Bunsen coefficients for ethylene in water (ranging from 0.069 to 0.226) for a range of temperatures and salinities that are relevant for aquatic nitrogen fixation. We apply these data to nitrogen fixation scenarios at different temperatures and salinities and stress the importance of using accurate Bunsen coefficients in nitrogen fixation assays.

Zuletzt aktualisiert am Donnerstag, den 17. Juni 2010 um 11:04 Uhr
  by