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A total of 11 sample-based estimators of tree species richness (S) are evaluated in terms of accuracy and precision in a Monte Carlo simulated simple random sampling from 39,779 forest inventory plots with 7.8 million trees belonging to 85 species. The plots represent a 108 million hectare forested region in central and eastern Canada. Sample sizes varied from 50 to 800. A weighted index combining estimates of accuracy and precision identified Chao's first estimator (CHAO1) as overall best with an estimator based on the assumption of a gamma mixed Poisson distribution of species occurrence as a close runner-up. The observed sample species richness was almost always the most negatively biased estimate. A sample size of 400-700 conventional fixed area forest inventory plots are needed to produce results with bias <20%. [ABSTRACT FROM AUTHOR]

Glossy buckthorn (Frangula alnus Mill.) is an alien species in Canada that is invading many forested areas. Glossy buckthorn has impacts on the biodiversity and productivity of invaded forests. Currently, we do not know much about the species' ecology and no thorough study of its distribution in temperate forests has been performed yet. As is often the case with invasive plant species, the phenology of glossy buckthorn differs from that of other indigenous plant species found in invaded communities. In the forests of eastern Canada, the main phenological difference is a delay in the shedding of glossy buckthorn leaves, which occurs later in the fall than for other indigenous tree species found in that region. Therefore, our objective was to use that phenological characteristic to map the spatial distribution of glossy buckthorn over a portion of southern Québec, Canada, using remote sensing-based approaches. We achieved this by applying a linear temporal unmixing model to a time series of the normalized difference vegetation index (NDVI) derived from Landsat 8 Operational Land Imager (OLI) images to create a map of the probability of the occurrence of glossy buckthorn for the study area. The map resulting from the temporal unmixing model shows an agreement of 69% with field estimates of glossy buckthorn occurrence measured in 121 plots distributed over the study area. Glossy buckthorn mapping accuracy was limited by evergreen species and by the spectral and spatial resolution of the Landsat 8 OLI. [ABSTRACT FROM AUTHOR]

Objectives: Despite physical literacy receiving increased attention as a potential gateway to physical activity participation, research establishing the link between physical literacy as a higher-order latent construct and physical activity is scant. The purpose of this study was to identify physical literacy profiles of children, and in turn, whether these profiles were associated with differences in physical activity participation., Methods: Design: Prospective cohort study. Children (N = 2015; 49% girls) completed a battery of measures to assess physical literacy (i.e., motor competence, confidence, motivation and enjoyment) in 5th grade. Physical activity participation was reported in the 5th and 8th grades. Latent profile analysis was applied to identify physical literacy profiles and estimate the effects of profile membership on physical activity participation., Results: Five unique profiles emerged including high (61.8%), moderate (19.8%) and low physical literacy (6.7%) as well as two inconsistent low physical literacy profiles characterized by divergent high enjoyment (9.7%) and very low enjoyment (2%). After adjusting for socioeconomic status and gender, physical activity participation was greatest among the high physical literacy profile, followed by the moderate physical literacy profile and was lowest across the three low physical literacy profiles. Differences in physical activity participation observed across the profiles remained consistent over time., Conclusions: This is the first time a person-centered approach has been applied to understand how the domains of physical literacy interact with each other to influence physical activity patterns. Results suggest physical literacy plays a formative role in shaping physical activity trajectories from a young age., (Copyright © 2020 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)