Examining the effects of sunlight and density on silver maple trees

Location: York University's woodlot Target adult silver maple trees that are twice our height were randomly chosen and their diameters were measured at breast height. A radius of 10m was measured using a transect from the target tree and each tree that was in that radius was counted. The sunlight percentage was estimated by seeing how much sky is shown throught the tree's canopy. A frame that was held up to the sky with our back facing the tree. The next target silver maple tree was chosen by walking 5m away from the previous radius. A total of 35 target trees were measured and radius counted.

采样地点为约克大学林地（York University's woodlot）。研究人员随机选取高度达人类身高两倍的成年银枫（silver maple）作为目标植株，对其胸径进行测量。以每棵目标树为起点，沿样带划定10米半径范围，统计该范围内的所有树木。光照百分比通过观测树冠缝隙中可见天空的占比进行估算：操作人员背对目标树，将观测框对准天空完成观测。下一棵目标银枫的选取方式为，从前一个采样半径的位置向外行走5米。本次采样共完成35棵目标树的胸径测量，并分别统计了各目标树对应10米半径范围内的树木数量。