Lab 4- Experimental Design

This experiment was conducted by 4 members who are Kristine Georgilopoulos-Gulli, Yu Xiao, Naz Naji and Winnie Zhao. This experiment was conducted on two days. Day 1 was on October 17th/ 2014 and Day 2 was on October 24th/ 2014. This experiment was conducted in the woodlot region at York University, Keele Campus. On day 1, 10 random Silver Maple trees were selected from the perimeter region of the woodlot and another 10 random Silver maple trees were selected from the non- perimeter region of the woodlot. The perimeter region is the area that is from the perimeter around the woodlot to 2 meters inside the woodlot. However, the non-perimeter region is the area that is 2- 8 meters inside the woodlot relative to the perimeter of the woodlot. This was a block experiment. Each of the 10 trees selected (for perimeter region and non-perimeter region) were tested for their height, girth, soil pH, soil moisture level, leaf abundance, canopy exposure to the sun, and leaf colour. The height of the tree was measured by having same member of the group observe the tree height of all the trees being tested. The measurement was relative, trees that were approximately 2 meters were considered medium, trees that were more than 2 meters were considered tall, and trees approximately taller than 3 meters were recorded as very tall. The girth of the tree was measured by one of the students using a transect measuring tape. The circumference of the tree trunk was measured and recorded in cm. The soil of the tree was measured by collecting about 1 teaspoon of the soil (within 10 cm around the tree) and placing in a plastic container containing approximately 5mL of water. The soil was then mixed with the water by shaking the plastic container a few times. Litmus paper was then placed in the water to measure the pH level of the soil. The moisture level of the soil was measured by having one of the members feel the soil with their hand. This was a relative measurement, dry soil received a rating of 0, soil with medium moisture received a rating of 1, and soil with a lot of moisture received a rating of 2. The leaf abundance of the tree being analyzed was determined through having one of the members observe the overall leaf abundance of the tree. Trees that barely lost any leaves received 100%, trees that lost half of their leaves received 50%, and trees that lost all of its leaves received 0%. This measurement was made by estimating percentage- wise. The canopy exposure to the sun was measured by having one of the members of the group observe the overall canopy exposure to the sun. Trees that had full exposure to the sun received a rating of 2, trees with medium exposure to the sun received a rating of 1, and trees with no exposure received a rating of 0. The leaf colour of the trees was determined through observing the colours of the leaves on the tree. On day 2, the exact procedure conducted on day 1 was also performed on day 2. However, different trees were selected to be tested, the trees that were analyzed on day 1 were not tested again on day 2.Overall 20 trees were tested from the perimeter region and 20 trees were tested from the non-perimeter region.