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Development of high-valued products through an integrated biorefinery approach is essential for the revival of the Canadian forest industry. Utilization of tree bark is one such example with considerable potential. The bark of trees contains a reservoir of phytochemicals that could be harnessed as value-added co-products. The objective of this study was to identify, characterize, and seek commercial potential of phytochemicals present in poplar bark. Industrially harvested poplar bark ( Populus tremuloides) was procured from Quebec. Water-soaked poplar bark was subjected to three steam-explosion treatments (treatments 1 to 3) using a steam-explosion reactor. During the experiment, extracts such as air purge, pre-steam purge, cooked purge, and pressed liquid were collected and subjected to compositional analysis. The results showed that the leftover bark residue even after the treatments was still fit for regular combustion for generating heat. Among the several identified phytochemicals (>100), furfural, 5-HMF, benzoic acid, salicylic acid, and catechol can be obtained as bulk chemicals, and sakuranin present at 15.9 % (extracted with acetone) as a high-valued and fine chemical. Considering the increasing demand for plant-based ingredients, there exists enormous potential to utilize these phytochemicals in agro-pharmaceutical industries. Further end-use studies, however, are required to ascertain the true economic potential of poplar bark phytochemicals. [ABSTRACT FROM AUTHOR]

Invasive species can alter the structure and function of the communities they invade, as well as lead to biotic homogenization across their invasive range, thus affecting large‐scale diversity patterns. The mechanisms by which invasive species can lead to biotic homogenization are poorly understood. We argue that invasive species acting as strong, deterministic, and consistent filters within and across invaded communities are likely to cause biotic homogenization at multiple spatial scales. We studied Bromus inermis Leyss. invasion into eight grasslands covering most of the grassland and parkland natural regions of Alberta (western Canada). Specifically, we tested whether B. inermis (1) has a strong impact on species richness and composition, (2) consistently alters resources (nutrients, light, and soil moisture), imposing the same ecological filter to species establishment and persistence across sites, and hence (3) whether it leads to biotic homogenization within and across sites. We recorded plant cover and resources across native‐to‐invaded transition areas combining space‐for‐time substitutions with time‐series data analyses. Bromus inermis invasion was associated with rapid biotic homogenization of communities, within and among the eight grasslands. The sharp changes in species relative abundances following invasion was the initial driver of biotic homogenization, and species loss was delayed. Supporting the idea that biotic homogenization can occur when an invasive species presents a broad and consistent filter, resources modified by B. inermis invasion (particularly light and certain nutrients) were altered rather consistently within and across sites. The 50% reduction in light was likely the initial driver of biotic homogenization, and the increase in nutrient availability probably facilitates the displacement of species from the invaded areas and could lead to the establishment of self‐reinforcing dynamics. Overall, our results support the idea that invaders acting as strong, deterministic, and consistent ecological filters are likely to cause biotic homogenization of the communities they invade. [ABSTRACT FROM AUTHOR]