Yorku. Woodlot. Sept20-2016.CVS

This study was conducted to measure the diameter at breast height (dbh) of adult trees in pairs and the distance between them in woodlots, at York University around 3:30pm- 5:00pm. Location: Data was collected at York University, at Keele St. and York Blvd, in the Woodlots. Methods: In this field experiment, transects measuring tapes were used to determine the distance between 10 pairs of sugar maple trees. The diameters were measured from the middle of the tree trunks, using a tape measure. Canopy coverage was determined by making square with fingers and holding it up, in order to gain an estimate regarding how much of the sky was seen. Key to variables: Diameter at breast height (dbh), distance to nearest species, and canopy coverage were continuous and quantitative variables. Prediction: It was predicted that the distance between two trees with a low dbh would be less than those with a greater dbh, since the smaller the dbh, the smaller the tree and therefore, the less branches and canopy coverage it would have. Thus, the space it occupies would be less and the trees could form closer to each other. Hypothesis: Tree pairs with lower dbh are closer to each other than pairs with greater dbh. Also canopy coverage is greater for trees with a higher dbh.

本研究旨在测定约克大学校园内林地中成年树木的胸径（diameter at breast height, dbh）及其成对植株间的间距，数据采集时间为当日下午3:30至5:00左右。
采集地点：数据采集于约克大学基尔街（Keele St.）与约克大道（York Blvd）交汇处的林地中。
研究方法：本次野外实验中，研究人员借助卷尺沿样带测量了10对糖枫（sugar maple）之间的间距；采用卷尺测量树干中部的直径；冠层覆盖率则通过双手摆出正方形框架并举至眼前，以此估算可见天空的占比来确定。
变量说明：本研究的连续定量变量包括胸径（diameter at breast height, dbh）、最近邻木间距以及冠层覆盖率。
研究预测：胸径较小的成对树木间间距将小于胸径较大的成对树木。原因在于，胸径越小，树木体型越小，枝条数量与冠层覆盖率亦越低，其所占据的空间更少，因此树木可更为紧密地生长。
研究假设：胸径更小的成对树木相较于胸径更大的成对树木，彼此间距更近；同时，胸径更大的树木冠层覆盖率更高。