User: | Open Learning Faculty Member:
I have selected to study the pattern of trees adjacent to and away from pathways in Stanley Park. Three locations along the environmental gradient include survey plots with a diameter of 3m located adjacent to a pathway, 10m away from the pathway, and 20m away from the pathway.
I observed a more diverse mix of trees immediately adjacent to paths as well as an abundance and rich diversity of herbaceous plants including shrubs, ferns and grasses. Ten meters away from the pathway I observed less deciduous tree species and reduced incidence of shrubs and other understory plants. At 20m away I observed mostly mature evergreen species with a limited understory.
My hypothesis is that increasing distance from a site of forest disturbance, such as a pathway, is correlated with lower tree species diversity, lower tree density, and larger tree size. Based on this hypothesis I would expect to see larger cedar and hemlock trees further from a pathway due to the lack of disturbance. The disturbance of a pathway would allow for new species of plants to establish due to the availability of sun, runoff from pathways, and additional space. Further, the clearing of the edges of pathways would allow for continual colonization of new plants.
The response variable is the number (continuous), type (categorical) and size (categorical due to slotting trees into size brackets) of trees in a plot. The predictor variable is distance from a pathway (categorical due to 3 distance measurements being used).
