Effects of industrial disturbances on the flavonoid concentration of Rhododendron groenlandicum

The boreal forest is subject to various anthropogenic disturbances, including logging, mining, and hydroelectricity production and transport. These disturbances affect Indigenous communities and the culturally salient species they depend on for the practice of traditional and subsistence activities. Rhododendron groenlandicum is one such species whose leaves are used to treat various ailments, due to their concentration in biologically active chemicals such as flavonoids. Our objective was to assess the effect of anthropogenic disturbances on the chemical properties of R. groenlandicum on the territories of three Indigenous communities. Leaf samples were collected near mines, under hydroelectric power lines, and in non-disturbed sites. Our results showed that variations in flavonoid concentration were mainly related to territory (R² = 0.43, P = 0.0005), while disturbance type had a smaller effect (R² = 0.18, P = 0.02). Samples from Nemaska, the northernmost territory with the most open forest stands, had higher concentrations of epicatechin (+23%, P = 0.03). Quercetin-3-glucoside concentrations were lower near mines (-19%, P = 0.01). The effects of disturbances on the chemical signature of R. groenlandicum are complex, and a complete assessment of the consequence of industrial activity on Indigenous landscape value must take into account other culturally salient species.