The Effect of Coloured Pan Traps and Floral Presence on Insect Abundance in Danby Grassland

The purpose of this experiment was to determine whether the location (presence of flowers vs. no flowers) and colour of pan traps affect insect abundance in a grassland environment. The grassland was a large open area covered with grasses. On October 15th 2015, twelve pan traps were set out in a location where there was an abundance of 20 or more flowers and twelve pan traps were placed in an area where there was no abundance of flowers, resulting in a total of twenty-four pan traps altogether. Pan traps measured the abundance of insects in the grassland. Coloured pan traps were used to attract an abundance of insects and to observe their reactions to the different colours. The colour pattern used was white, blue and yellow and there were 8 pans per colour. Samples were collected systematically. One line transect was placed 4m along an area where there were 20 or more flowers to indicate a floral site. A second line transect was placed 4m along an area where there were no flowers to indicate a site with no floral presence. At each metre along each transect, three pan traps were placed perpendicular to the line transect in the consistent order of white, blue and yellow resulting in a total of 24 pan traps – 12 per site. Thus, the white pan trap was the closest to the transect whereas the yellow pan trap was placed the farthest. Soapy water was added halfway to each of the pan traps in order to trap the insects and submerge them into our pans for the duration of our experiment. After approximately two hours, data was collected and abundance of insects in each pan trap was recorded. Abundance measured the total number of insects observed in each pan trap. The experiment was repeated once more after exactly one week on October 22nd 2015. The setting of the experiment took place in the Danby grassland area on the northeast side of York University Keele Campus for the duration of approximately three hours on October 15th, 2015 (2:45-4:30pm) and October 22nd, 2015 (2:45-5:00pm). On October 15th, it was 17 degrees Celsius with 39% humidity and SW winds at 23 km/h indicating a fresh breeze on the Beaufort scale. The pressure was 1009mb and visibility was 16.1km. On October 22nd, it was 14 degrees Celsius with 59% humidity and NW winds at 29km/h indicating a strong breeze on the Beaufort scale. The pressure was 1019mb and visibility was 16.1km. Each of the 4 members – Simranjit Kang, Ava Kamali, Katrin Chapkis, Jennifer Mariathas – of group 4 contributed to collecting the data. We used coloured pan traps, soapy water and transects to analyze and record the dataset. Sample size is 48.本实验旨在探究皿式诱捕器（pan traps）的布设位置（有花区域与无花区域）与颜色是否会影响草原生境中的昆虫丰度。本次实验的草原生境为一片覆盖草本植物的大型开阔区域。2015年10月15日，研究人员在花卉丰度达20朵及以上的区域布设12个皿式诱捕器，并在无大量花卉的区域布设12个，总计24个皿式诱捕器。皿式诱捕器用于监测草原生境中的昆虫丰度，研究采用彩色诱捕器以吸引昆虫并观测其对不同颜色的趋性反应。本次实验所用的诱捕器颜色为白色、蓝色与黄色，每种颜色各设置8个。样本采集采用系统采样法：在多花区域沿样带设置4米的样线以标记花境样地，在无花区域同样设置4米样线以标记非花境样地；沿每条样线每1米处，垂直于样线按照固定顺序（白、蓝、黄）布设3个皿式诱捕器，每个样带共布设12个，两个样带总计24个诱捕器，因此白色诱捕器最靠近样线，黄色诱捕器距离样线最远。每个皿式诱捕器中加入半量的肥皂水，用以捕获昆虫并使其浸没于容器内。约2小时后收集样本，记录每个诱捕器中的昆虫丰度，即单诱捕器内观测到的昆虫总数量。实验于一周后即2015年10月22日重复开展一次。本次实验的场地位于约克大学（York University）基尔校区东北部的丹比草原（Danby grassland）区域，两次实验的开展时长均约3小时：2015年10月15日为14:45-16:30，2015年10月22日为14:45-17:00。2015年10月15日的实验当日气象条件为：气温17摄氏度，相对湿度39%，西南风风速23km/h，对应蒲福风级的清劲风；气压1009毫巴，能见度16.1km。2015年10月22日的气象条件为：气温14摄氏度，相对湿度59%，西北风风速29km/h，对应蒲福风级的强风；气压1019毫巴，能见度16.1km。本实验第4小组的4名成员——Simranjit Kang、Ava Kamali、Katrin Chapkis与Jennifer Mariathas——均参与了数据收集工作。本次研究采用彩色皿式诱捕器、肥皂水与样带法开展数据集的采集与记录工作，样本总量为48。