Perimeter and Non-Perimeter Woodlot Maple Trees

The data for “Perimeter and Non-Perimeter Woodlot Maple Trees” was collected over a two-day collection period at the woodlot area at York University-Keele Campus in Toronto Ontario. The first day of data collection took place on Friday October 17, 2014 from 15:00-15:45. Weather conditions included heavy cloud cover, moderately windy conditions and a temperature of approximately 10 degrees Celsius. Researchers wanted to study the relationship between the relative location of adult maple trees in the woodlot area and the canopy abundance during the autumn season. Researchers proceeded to explore additional abiotic variables that may affect the number of leaves remaining on the tree. Alongside to leaf abundance (%) and relative location of the tree, researchers observed and recorded six additional variables, including: tree height, girth of trunk, soil pH, moisture level, canopy exposure to direct sunlight and leaf colour. On the first day of data collection, researchers observed ten randomly selected “perimeter” adult maple trees found along the southern edge of the woodlot area and ten “non-perimeter” adult maple trees. Any maple tree that fell within a 2-metre radius from the outer edge was considered “perimeter” tree, while any maple tree that fell beyond an 8-metre radius from the outer edge was considered “non-perimeter”. The second day of data collection took place on Friday October 24, 2014 from 15:00-15:45. Weather conditions included fairly clear skies, light cloud cover and a temperature of approximately 12 degrees Celsius. On the second day of data collection, researchers observed ten randomly selected “perimeter” adult maple trees found along the northern edge of the woodlot area and ten “non-perimeter” adult maple trees. The same criterion to distinguish perimeter from non-perimeter trees was employed. The same researcher determined the relative height of each tree in all sets of data collection by observation. Simple qualitative descriptions of tree height were recorded for each tree. The girth of each tree at researcher breast-level was measured and recorded using a transect tape for each tree. A simple litmus paper test was employed to measure the pH of the soil immediately surrounding the base of the tree. Soil pH provides an indication of the nutrients and minerals that tree receives in its habitat. A small sample of soil was added to a container filled with distilled water, after which a strip of litmus paper was added. The pH value was obtained by comparing the resulting colour change on the litmus paper to given pH values. The exposure of the main canopy to direct sunlight was observed and recorded as a percentage by the same researcher across all datasets. The moisture level of the soil immediately surrounding the base of the tree was felt by touch and rated on a relative 0-2 scale, where 0 indicated “dry” and 2 indicated “wet”. The overall abundance of leaves on each tree was observed by the same researcher and recorded as a percentage. The leaf colour(s) on each tree were observed and recorded. General descriptions of colour were employed in describing leaf colour. Participating researchers included: Kristina, Naz and Yu.本数据集名为"林缘与非林缘枫树林（Perimeter and Non-Perimeter Woodlot Maple Trees）"，其采集工作于安大略省多伦多市约克大学基尔校区的林地范围内开展，共历时两个采集日。 首次数据采集于2014年10月17日星期五15:00至15:45进行，当日天气为多云密布、风力中等，气温约10摄氏度。本次研究旨在探究林地内成年枫树的相对位置与秋季冠层（canopy）丰度之间的关联，同时探索可能影响树木留存叶片数量的其他非生物变量（abiotic variables）。除叶片丰度（以百分比形式记录）与树木相对位置外，研究团队还观测并记录了六项额外变量：树高、树干胸径（girth of trunk）、土壤pH值（soil pH）、土壤湿度、冠层直射日照暴露度以及叶片颜色。 首日采集共随机选取林地南部边缘的10株"林缘（perimeter）"成年枫树，以及10株"非林缘（non-perimeter）"成年枫树。其中，距林缘外边缘2米范围内的枫树被定义为"林缘个体"，而距外边缘8米以外的枫树则被归类为"非林缘个体"。 第二次数据采集于2014年10月24日星期五15:00至15:45开展，当日天气晴好、少量多云，气温约12摄氏度。次日采集共随机选取林地北部边缘的10株"林缘"成年枫树与10株"非林缘"成年枫树，沿用相同的分类标准进行个体区分。 所有数据采集环节中，均由同一名研究人员通过目视估算确定每株树木的相对高度，并以定性描述的形式记录每株树的树高等级。使用胸径围尺测量每株树的胸径并记录；采用石蕊试纸测试（litmus paper test）测量树木基部周边的土壤pH值：先取少量土壤样本放入盛有蒸馏水（distilled water）的容器中，再置入石蕊试纸，通过比对试纸变色结果与标准pH色卡得到pH数值。冠层主枝接受直射日照的比例由同一名研究人员统一观测并以百分比形式记录。树木基部周边的土壤湿度通过触摸感知，并采用0-2的相对等级进行评分，其中0代表"干燥"，2代表"湿润"。每株树的整体叶片丰度由该研究人员目视估算并以百分比形式记录，同时观测并记录叶片颜色，采用通用颜色描述对叶片色泽进行标注。 本次研究的参与人员包括Kristina、Naz与Yu。