The Impact of Habitat on Animal and Plant Abundance and Diversity

MethodThis experiment was conducted by Arian Nouraee, Setareh Rezvani, Khondoker Sadid, and Ellora Arockiadoss on a slightly foggy day with a climate of 18° C at the disturbed open space and grasslands area at Saywell Woods at York University on Monday October 3, 2016 at approximately 3:00 PM. Survey method, quadrats: The quadrats were placed every 2 meters along a 50 meter transect placed at random in both the grassland and open disturbed areas. 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 each 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, for each of the two aforementioned sites. Survey method, transect: A 50 meter transect was obtained and placed in both the disturbed open space area and the grasslands area. 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 in both the open disturbed and grassland areas over a span of 15 minutes. Additionally, the abundance of invertebrates was collected within a 5 metre radius in both the open disturbed and grassland 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 bowls 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. This data set was conducted at both the grasslands and the open disturbed area. 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 at both the grassland and open disturbed areas for a total of 10 replicates at each area.Metadata: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 studiedExotic 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 studiedCensus is a categorial variable that represents the sampling week. For example, week 5 = census 1, week 7 = census 2.Calendar date is a continuous variable that represents the date the data was collected.Campus is a categorical variable that provides information on which campus this data was acquired.Group ID is a categorial variable that allows the group that acquired this data to be identified.Habitat is a categorical variable that provides information for where this data was acquired specifically.Rep is a discrete variable that represents the replicate number of the dataset.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 discrete 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. This variable was used to differente between two different species of birds that were observed (seagull and small black bird).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. Hypothesis:There will be a higher abundance and diversity of animals and plants found in the grasslands than in the disturbed open space because the disturbed woodlots are primarily inhabited by humans, causing the animals and plants to either go extinct or to migrate to neighbouring sheltering areas.Predictions: The vegetative ground cover in the grasslands will be higher in the disturbed open space because there is a higher diversity of plants that will take up the grassland space, whereas the disturbed open space mostly makes up grass. The abundance of humans in the disturbed open space will be higher than the grasslands. There are a higher number of flowers in the grasslands than in the open disturbed area because the flowers were able to thrive without much disturbance by human activity.