A Study on the Relative Distance Between Adult Trees and Their Diameter at Breast Height.

Metadata:

Distance
to Next Tree: To measure the distance between adult
tees (in metres), a transect measuring tape was used and the center of one tree
trunk was measured to the center of another tree’s tree trunk. (Numerical
variable) The distances between trees varied from 2.1 to 7.2m.
Diameter
at Breast Height: A measuring tape was used and the
diameter was measured against the tree trunk at approximately my chest height
around 158 cm. (Numerical Variable) The diameters of the trees at breast height
varied from 0.13m to 0.42m.

Condition
of Tree: 
This was determined based on a scale; 0=dead, 1=living, and 2=huge green
canopy. (Response variable, Categorical)
Methods: A 30m transect measuring tape was used to
measure the distance (in metres) between two adult trees that were encountered
and the data was recorded onto a table. 
Adult trees were selected if they lied on a straight line from the edge
of the forest towards the centre. To meet the conditions of an adult tree, the
tree had to be at least 0.1m in diameter and at least double my height (188cm).
Furthermore, to measure the diameter of the trees at breast height, each tree
was measured at approximately my chest height of 158cm using a measuring tape.
To measure the distance between each tree, we measured from the centre of the
first tree to the centre of the next tree. The condition of the tree was
determined by the lab group’s observations; each person in the group determined
what condition the tree was in on a scale of 0-2. 0 represented the tree being
dead and 2 meant the tree was healthy with a lush green canopy. In total, 10
trees were observed to compile the data from this woodlot.
Study Site Description: A field study was conducted at the Danby
Woodlot located on York University’s campus near Keele Street and York
Boulevard in Toronto, Ontario on September 22nd 2016, around 2:30
pm. The temperature was around 27 degrees Celsius, with sun and cloud, and a
few hours into the study, a few raindrops began to fall.  The woodlot was covered with lots of broken
branches, leaves, soil, and was shady because of the large canopy trees.
Hypothesis: The distance between the adult
trees and the diameter at breast height will both have an effect on the tree’s
growth conditions. The greater the distance between the trees, lack of
competition results in greater nutrition and resources such as sunlight and
space. Trees that are able to grow big, that have big trunks and have a large
lush green canopy will be able to better, capture sunlight and resources
compared to smaller trees.  

Prediction 1: The greater the diameter of
the tree at breast height, the worse the condition will be of the nearby tree.

Prediction 2: Trees that are farther apart
from another will have healthier growing conditions.

Prediction 3:  The thicker the trunk of the tree, the tree
will be healthier (example: lush canopy). 

Group Members: Keerthana Balachandran, Matthew Chiang, Andrew Nguyen, and Kobina Vijayakumar