The Diversity and Abundance of Insect Species in a Grassland, and a Woodlot

Group Members: Loyal Tran, Anisa Amin, James Quach, Iiman Darman The group was split into two to save time; dataset 1 was collected with Loyal Tran. This data was collected at the Danby woodlot, and the grassland next to it on September 30, 2015 from 15:15 to 16:10. A 1m x 1m quadrat was used to collect 20 random samples, 10 from the grassland, and the other 10 from the woodlot. It was a sunny day with a few clouds in the sky. The weather was 16 degrees Celsius with a cool breeze. The ground was cool and damp as it was raining the day before. Insect abundance and number of RTU's was determined in each sample. Insect abundance is defined as the total number of insects in a quadrat and was determined by counting the total number of insects seen within 1 minute of observation. Each sample was observed for 1 minute. The environment in the quadrat was disturbed (i.e. moving plants, scattering the soil, etc.) as to see the insects that may have been hidden in the soil or by the surrounding vegetation. This allowed for us to observe many more individuals and RTU's. Number of RTU's is an estimate of the number of species and is defined as the number of different recognizable taxonomic units. This was determined by counting individuals with different physical characteristics. Any individuals that had major differences in physical characteristics were counted thought of as 2 RTU's. This data may be prone to error as visual observation is imprecise. Insects may have been camouflaged, too small, or hidden under surrounding vegetation or the soil. All of these characteristics may have affected the precision of this data.

项目组成员：Loyal Tran、Anisa Amin、James Quach、Iiman Darman。为提升作业效率，团队拆分两组开展工作；数据集1由Loyal Tran负责采集。该数据集的采集工作于2015年9月30日15:15至16:10，在丹比林地（Danby woodlot）及其毗邻的草地开展。研究采用1m×1m的样方（quadrat），共采集20份随机样本，其中10份采自草地，剩余10份采自林地。当日晴好，偶有薄云，气温16摄氏度，伴随微凉微风；因前一日曾降雨，地表凉爽湿润。本研究针对每份样本测定昆虫丰度（insect abundance）与可识别分类单元（Recognizable Taxonomic Units，RTU）数量。其中，昆虫丰度定义为样方内昆虫总数量，通过1分钟观测期内目击的昆虫总数统计得到，每份样本的观测时长均为1分钟。为暴露潜藏于土壤或周边植被中的昆虫，研究人员对样方内的生境进行了扰动（如翻动植株、疏松土壤等），此举可提升观测到的昆虫个体与RTU的数量。RTU数量为物种数的估算值，指不同可识别分类单元的总数，通过统计具有显著物理特征差异的个体得到——凡物理特征存在明显差异的个体，均被计为2个不同的RTU。由于本研究采用目视观测法，数据存在一定误差风险：昆虫可能存在拟态、体型过小，或潜藏于周边植被与土壤中等情况，均可能影响数据的精确性。