HEIRARCHICAL VARIATION IN DECOMPOSITION RATES ACROSS SOUTHERN ONTARIO REFERENCE STREAMS
The cotton strip assay (CSA) has been promoted as a method to study the rate of organic-matter decomposition, as a means of incorporating functional indicators into standardized river assessments. However, operationalization of the CSA as an indicator requires testing the spatial and temporal controls of variance in decomposition of cotton strips at regional reference sites. We conducted a hierarchically structured study of decomposition rates in Ontario, Canada. Cotton strips were deployed during the spring, summer and autumn in pool and riffle habitats of 22 streams located in three distinct physiographic regions. Partitioning of variation among hierarchical scales associated with rates of decomposition will be examined using nested ANOVAs. In addition, a PLS regression analysis will be performed to identify environmental variables associated with decomposition patterns. We anticipate that seasonal and regional-scale differences will account for the majority of variation in decomposition rates, whereby temperature and nutrients will be the primary environmental controls of decomposition. By quantifying the natural heterogeneity in decomposition rates, this study will inform biomonitoring practices, enabling progress towards inclusion of the CSA in regional monitoring programs.
Jenna R. Webb (Primary Presenter/Author), Western University & Canadian Rivers Institute, firstname.lastname@example.org;
Kristin J. Painter (Co-Presenter/Co-Author), Western University & Canadian Rivers Institute, email@example.com;
Nolan J.T. Pearce (Co-Presenter/Co-Author), Western University & Canadian Rivers Institute, firstname.lastname@example.org;
Robert Bailey (Co-Presenter/Co-Author), University of Ontario Institute of Technology, email@example.com;
Scott Tiegs (Co-Presenter/Co-Author), Dept. of Biological Sciences, Oakland University, firstname.lastname@example.org;
Adam G. Yates (Co-Presenter/Co-Author), Western University & Canadian Rivers Institute, email@example.com;