Dr. Sina Adl, Professor and Head, Department of Soil Science, College of Agriculture & Bioresources,University of Saskatchewan, presented a seminar, "The neglected role of protists in soils:implications for diversity, nutrient cycling and reclamation," on 20 September 2012.

Abstract: The unicellular eukaryotes (protists) have been neglected in soil studies, in part because their diversity was hugely underestimated until very recently, and in part because traditional “soil protozoa” techniques have turned out to be inadequate. Molecular phylogenies and recent studies have revealed the extent of species diversity, and thus diversity of ecological functions and niches occupied by these species. We have used stable isotope studies to quantify the amount of nutrients through the bacteria and protist food web pathway. These are complemented by functional response curve data. Calculations indicate protists can ingest as much as about one standing biomass of active bacteria per day. Protist diversity recovery from disturbance (tillage, mining, clear-cutting) can take about 15-25 years. These kinds of results indicate that soil models have underestimated the bioindicator potential and contributions of protists to soil nutrient cycling.