Determining the effect of the invasive species Rhamnus cathartica in the native habitat of the Acer saccharinum

Our group went out on the afternoon of October 15, 2014 and again on October 22, 2014 to the Danby Woodlot located on York University’s Keele Campus in Toronto, Canada and placed a total of 12 quadrats created by four transect tapes, each enclosing an area of 20ft by 20ft. The first quadrat was placed at one corner of the woodlot and the quadrats continued in a diagonal fashion almost reaching the opposite corner of the woodlot. We counted the number of Common Buckthorns (Rhamnus cathartica) as well as the number of Silver Maples (Acer saccharinum) within the confines of the quadrat and included any individuals that were in contact with the transect tape line. A count of all the trees, regardless of species, was also taken for other calculations such as relative density. DBH, or diameter at breast height, was also measured and recorded. This was done by one individual in our group to ensure consistency of the breast height and accuracy of the measurement of the specie's diameter which was calculated in inches with another transect tape.

2014年10月15日下午与10月22日下午，我们团队先后两次前往位于加拿大多伦多约克大学基尔校区的丹比林地（Danby Woodlot），布设了总计12个样方（quadrat）。每个样方由4条样带（transect tape）围成，单样方面积为20英尺×20英尺。首个样方设置于林地的一角，后续样方沿对角线方向依次布设，几乎延伸至林地的对角区域。我们对样方范围内的普通鼠李（Common Buckthorns，Rhamnus cathartica）与银枫（Silver Maples，Acer saccharinum）的个体数量进行了统计，凡与样带边线接触的树木个体均被纳入计数范围。此外，我们还统计了样方内所有树木的总数量（不分物种），用于相对密度等后续计算。胸径（diameter at breast height，DBH）同样得到测量与记录：为确保胸高测量位置的一致性与物种直径测量的准确性，该测量由团队中的同一名成员完成，测量单位为英寸，所用工具为另一条样带。