Analysis on Plantago Major Plants Development Dased on the Effect of Resource Competition by Crowding on Plant Sunlight Exposure and Leaf Size at York University

The purpose of this experiment was to examine the effect of resource competition and distribution on plants inhabiting grasslands through quadrat sampling technique. Data collection for this study was obtained on the Mondays of 19th and 26th of October 2015 between 3:00 pm – 5:00 pm at the Dandy grasslands of York University. On both collection days, site conditions exhibited temperature ranging from 11°C – 15°C with cool and breezy wind conditions. The data collection for this study was performed by a group comprising of Aziza, Paula, Sahar and Shahana. It was hypothesized that as resource competition increases and plant distribution increases, growth and development of target species will be negatively affected due to reduced accessibility of Plantago major plants to resources such as sunlight essential for growth. This hypothesis was tested through examination of the following variables: average leaf size, crowding, total number of leaves, total number of leaves exposed to sunlight and sunlight percentage. Sampling technique used in this experiment was the quadrats placed at random within target location in order to examine the distribution of the target plant species. Each data collection day produced 70 replicates of sampling Plantago major plants that totalled to 140 replicates by the end of the second day. Crowding was determined by assessment of the density of other plant species relative to the Plantago major plant in one quadrat. The length of Plantago major leaf was measured from the stem of the plant to the tip of the leaf using the measuring tape. The average length was then calculated for each individual Plantago major plant. Sunlight exposure, presented in percentage, was calculated by dividing the number of leaves exposed to sunlight of each individual plant by the total number of leaves from the same plant. It should be noted that this variable is sensitive to time of day and location as exposure to sunlight and shade is relative to the time of day. It was observed that dropping temperature due to season change may have an influence in the abundance of Plantago major plants in grasslands as different species of plants as well as target species prepare for the coming cold temperatures.

本实验旨在通过样方采样法，探究资源竞争与分布对草原植物的影响。本研究的数据采集工作于2015年10月19日与26日两个周一的下午3:00至5:00期间，在约克大学（York University）丹迪草原（Dandy grasslands）开展。两日采样现场的气温介于11℃至15℃之间，天气凉爽且多风。数据采集由Aziza、Paula、Sahar与Shahana组成的小组完成。本实验提出如下假说：随着资源竞争加剧与植物分布范围扩张，目标物种的生长发育将受到负面影响，原因在于大车前草（Plantago major）获取生长必需的光照等资源的途径被缩减。该假说通过以下变量进行验证：平均叶大小、拥挤度、总叶片数、受光叶片数以及光照百分比。本实验采用随机放置于目标区域内的样方，以探究目标植物物种的分布特征。每个采样日均完成70组大车前草的采样重复，两日累计共获得140组采样重复样本。拥挤度通过评估单个样方内其他植物物种相对于大车前草的种群密度来确定。使用卷尺测量大车前草的叶片长度，测量起点为植株茎部，终点为叶尖，随后计算单株大车前草的平均叶长。以百分比形式呈现的光照暴露率，通过将单株植物的受光叶片数除以该植株的总叶片数计算得出。需注意的是，该变量受当日时段与采样位置的影响显著，因为光照与遮阴情况随当日时段发生相对变化。本研究同时观察到，随季节转变出现的气温下降，可能对草原中大车前草的种群丰度产生影响——此时各类植物与目标物种均在为即将到来的低温环境做好适应性准备。