Sydney Bobey | ALES Graduate Seminar

Event details: A graduate exam seminar is a presentation of the student’s final research project for their degree. This is an ALES MSc Final Exam Seminar by Sydney Bobey. This seminar is open to the general public to attend.

Zoom Link:  https://ualberta-ca.zoom.us/j/98655482081?pwd=jsGd49koArNikz39Fiouhi7KAyVSGf.1

MSc with Dr. Robert Froese

Thesis Topic:  Plant community response to operational use of glyphosate for conifer release

Abstract:

Glyphosate (N-(phosphonomethyl) glycine) is the active ingredient in many commercially used herbicide formulations. Primarily manufactured by Bayer Group (formerly Monsanto Company), these herbicides are cost-effective, non-selective, and degrade relatively quickly, making them desirable for both agriculture and forest industries. In Alberta, glyphosate-based herbicides are commonly used to control vegetative competition during reforestation, primarily with the goal of aiding conifer release. However, concerns persist about potential negative impacts of glyphosate on human and animal health, biodiversity, forest composition, and ecological succession, which has compelled government and industry to re-evaluate the use of glyphosate for operational forestry purposes. The objective of this research is to assess the persistence of glyphosate within operationally treated forestry cut-blocks to evaluate plant biomass recovery, potential exposure of wildlife through browse, species diversity, and plant community change. Data were collected throughout thirty-nine recently treated planted cut-blocks across western Alberta over three years, and glyphosate concentration was quantified for eighteen plant species of interest. Biomass sampling was used to estimate biomass of available browse, and nonmetric multidimensional scaling (NMDS) ordinations were done to evaluate plant community change. Results indicate minimal persistence of glyphosate at one-year post-treatment, and further rapid decline. Preferred ungulate browse species are initially reduced, and many do not exhibit significant recovery within the study period, suggesting limited potential for wildlife exposure to glyphosate through browse. Glyphosate has the strongest influence on plant community composition in the first year following application; however, in subsequent years, shifts in community structure appear to be more closely driven by climatic factors. This suggests that glyphosate persisting within plant tissues does not adversely impact the community composition when used for operational forestry purposes.