DOI: 10.6084/m9.figshare.4056168
title: The Impacts of Canopy Cover on Species Abundance in a Woodlot Habitat

description: <b>Methods</b> This experiment was conducted by Setareh Rezvani, Khondoker Sadid, Arian Nouraee and Ellora Arockiadoss on a windy day with a climate of 7° C in the woodlot (43.768756, -79.5079) at York University on Monday October 24, 2016 at approximately 3:00 PM. Survey method, quadrats: The quadrats, each sized to 1 meter by 1 meter, were placed every 2 meters along a 50 meter transect placed at random throughout the forest. For each replicate, the quadrat was placed either on the left side of the transect for odd quadrat replicate numbers, or right side for even quadrat replicate number. First, the number of individuals belonging to species native to the site was counted (native abundance), followed by a count of the number of species that are exotic to the site (exotic abundance), and lastly the number of flower heads present in each quadrat. Native and exotic species were identified and differentiated with help from the experiment supervisor (TA). This was repeated for a total of 25 times replicates up to the entire length of the transect. Survey method, transect: A 50 meter transect was obtained and placed from one end of the woodlot to the other. At every two meters, the abundance of woody plants that was within 0.5 meters on either side of the transect was recorded. Additionally, the canopy coverage, vegetative ground coverage, and total number of flowers were also recorded at 2 m intervals on the transect. A total of 25 replicates were obtained in this data set. Survey method, point survey: Using the 50 meter transect, the abundance and species of vertebrates, as well as the number of humans that did not belong to the lab was collected within a 50 meter radius of the woodlot over a span of 15 minutes. Additionally, the abundance of invertebrates was collected within a 5 metre radius in the woodlot area over a span of 15 minutes. Survey method, pan trap: Using the 50 meter transect, six solo bowls were set 3 meters apart at distances of 0 meters, 3 meters, 6 meters, 9 meters, 12 meters, and 15 meters parallel to the transect. The six yellow, blue and white bowls in alternating colours were then filled with soap water to about ¾ full and were left undisturbed for 45 minutes. At the end, the number of insects present within the bowls were accounted for within the woodlot. Survey method, sweep net: A 50 meter transect was placed. Using a sweep net, the number of invertebrates captured along the 50 meters was measured and recorded. After the first measurement, the remainder of the calculations were walked in distances of 1 or 2 meters away from the transect but continued 50 meters parallel to the transect. This procedure was conducted in the woodlot for a total of 10 replicates at each area. <b>Metadata:</b> Native abundance is a discrete variable that provides the total number of individuals observed within the area of the quadrat belonging to species that have been identified as native to the site being studied. Exotic abundance is a discrete variable that provides the total number of individuals observed within the area of the quadrat belonging to species that have been identified as exotic to the site being studied Abundance of woody plants is a discrete variable that provides the number of woody plants found in each sample replicate. A woody plant is defined as a tree greater than 1.5 meters in height. Canopy cover is a continuous variable that provides the percentage of canopy coverage that was observed when looking towards the sky in each sample replicate. Ground cover is a discrete variable that provides the percentage of vegetative ground cover in each sample replicate. Vegetative ground cover was visually identified as grass. Number of flowers is a discrete variable that provides the total number of flowers in each sample replicate. Flowers were identified as any plant with a blooming bud. Abundance of vertebrates (eg. birds, squirrels, rabbits) is a discrete variable that measures the number of individual vertebrates in a 50 metre radius over a period of 15 minutes. Vertebrate species is a discrete variable that shows the number of different species that were observed in a 50 metre radius over a period of 15 minutes. Abundance of humans is a discrete variable that provides the number of human beings which were visualized within a 50 metre radius over 15 minutes. Abundance of invertebrates is a discrete variable which accounted for the total number of insects such as ants, flies, bees and dragonflies that were found in each sample within a 5 metre radius over a 15 minute period. Abundance invertebrates pan traps is a discrete variable that represents the number of invertebrates captured in the solo bowls filled with soap after 45 minutes. Abundance invertebrates sweeps is a discrete variables is a discrete variable that represents the number of invertebrates captured in the sweep net along a 50 m transect. <b>Hypothesis:</b>There will be higher abundance and diversity of wooded plants than herbaceous plants in the woodlot area due to the lack of sunlight filtering through the dense canopy cover (less light for herbaceous plants). This leads to amensalism between herbaceous and wooded plants, as herbaceous species are negatively affected by the presence of wooded plants, while wooded plants are unaffected by herbaceous plants.<br><b>Predictions</b>1. Abundance of herbaceous plant species will be lower than wooded plants in the woodlot2. As canopy cover in the woodlot increases, abundance of herbaceous plant species will decrease 3. Abundance of invertebrates and vertebrates will increase as canopy cover increases due to the shade (protection from sunlight) provided by the presence of wooded plants.