Lab 3- Insect Abundance

The objective of this experiment was to use random sampling through the method of quadrats to measure the abundance of various insects in the grassland and woodland. The samples were collected by Huda and Ratiba. To obtain the abundance, 1m2 quadrat was placed randomly and plot was observed for thirty seconds using the timer on the phone. The samples 1 to 10 were taken in the grassland, and sample 11 to 20 were taken in the woodland. To begin with, the vegetation in the plot was not touched, or moved to see the insects beneath it. Instead, the insects were observed from a bird’s eye view. During the thirty second interval all the insects flying into the plot or crawling were recorded. The insects were identified by random recognizable taxonomic units during the thirty second observation. The list of features used to identify the insects are: spider- (black, light beige) and eight legs, bees-pair of wings, black and yellow stripes and six legs, ants-six legs, crawling, and brown and the flies- one set of wings, absence of yellow and black stripes. The RTUs and a tally mark (abundance) was recorded by the observers. The tally marks were used to record abundance as it was uncertain as to how many insects of the same taxonomic group would enter the plot. Later, the tally marks for abundance were counted and recorded in the data sheet as numerical values as it would make data analysis easier.

本实验旨在采用样方（quadrats）随机抽样法，测定草原与林地中各类昆虫的种群丰度。本次采样工作由Huda与Ratiba完成。

为获取种群丰度数据，我们随机放置1平方米样方，通过手机计时器计时，对样地开展30秒的观察。样本1至10采集自草原生境，样本11至20则采集自林地生境。

实验初始阶段，我们不会触碰或移动样地内的植被以探查下方藏匿的昆虫，而是采用俯视视角开展观察。在30秒的观察周期内，所有飞入或爬入样地的昆虫均需记录在册。本次观察期间，通过可识别分类单元（Recognizable Taxonomic Units，RTUs）对昆虫进行分类识别。

用于昆虫识别的形态特征清单如下：蜘蛛——体色为黑色或浅米色，具8条步足；蜜蜂——具一对翅，带有黑黄相间条纹，且具6条步足；蚂蚁——具6条步足，营爬行活动，体色呈棕色；蝇类——仅具一对翅，无黑黄相间条纹。

观测者需记录各可识别分类单元及其计数标记（即种群丰度）。由于无法确定同一分类类群会有多少只昆虫进入样地，因此采用计数标记法记录种群丰度。后续，观测者会对计数标记进行统计，并将结果以数值形式录入数据表，以简化后续数据分析流程。