Robert E.A. Boudreau, George Carmody and James J. Cheetham
PLAIN-LANGUAGE SUMMARY:
Pareto analysis is a method that can determine which variable in a set of chemical or physical parameters is most important in determining measured output. A macro for Excel™ was developed and successfully applied to a set of population abundances for four protists in order to determine which variable was most important; pH, salinity or oxygen content. It was found that Cribroelphidium gunteri, a foraminifera, thrived under conditions of high oxygen content and high salinity, but decreased in abundance with an increase in pH. Centropyxis aculeata, an arcellacean, decreased in abundance with an increase in salinity above 5 parts per thousand. Difflugia corona, another arcellacean, experienced a decreased abundance when salt content increased. Lagenodifflugia vas, a third arcellacean, was not sensitive to an increase in the three variables tested. This macro allows rapid identification of the most important variables in determining abundances of protists (arcellaceans and foraminifera) in an environmental setting.