BIOL 2050 Data Set 2 Pan Traps

Meta DataColour: The colour of the plastic bowl used for one single pan trap set on the ground in a line one meter away from the other colour bowls. The pan traps were set in an alternating pattern: yellow, light blue, dark blue, white. The colour of the pan trap was judged by the naked eye in comparison to one another. Site: The specific habitat type to which the pan traps were placed. The pan traps were set either deep in Danby Woodlot represented by “woodlot” or in a grassland area beside the woodlot represented by “grassland”. Locations were determined by sight of trees; wooded area with many trees, leaves and twigs was considered woodlot whereas the more open field with tall plants was considered grassland. Abundance: The total number of individual insects visible in the soapy water of one single pan trap one hour after it had been set. Insects were counted by sight. Any species with recognizable morphology of insects were considered. Any individuals not in the soapy water were excluded from the count. Pan traps used were of identical size and contained relatively equal volumes of soapy water. Different RTU’s: The number of different recognizable taxonomic units per pan trap. Any insect with clear morphological characteristics unique to other insects in the pan trap were considered an individual taxonomic unit. The taxonomic units were counted by sight. Any insects not in the soapy water were excluded from the count. Pan traps used were of identical size and contained relatively equal volumes of soapy water. Data was collected in the Danby Woodlot and Danby Grassland found outside of York University campus on a Wednesday of September around 4:15pm. Skies were moderately clear with temperate winds and a temperature of 18oC. The woodlot consisted of a very shaded area containing many trees and vegetation. Twigs, leaves, branches and human litter covered the ground. The grassland consisted of an open area with many tall plants and flowers reaching heights of approximately 1m. A dispersed crowd of 18 York University students and one TA were walking within both habitat types collecting different samples. HypothesisIt is hypothesized that both colour and location of the pan trap will affect the number and variety of insects found in a given area since different types of insects may prefer a specific habitat or colour over another.PredictionIt is predicted that the yellow and white pan traps will contain a higher abundance and variety of insects than the other colours because they resemble common flower colours which will attract more insects of different taxonomic units. It is predicted that the woodlot will have a higher abundance of insects with a variety of taxonomic units because the numerous trees in the area provide both nutrients and shelter to many insects of different types. Material and MethodsA 10m strip of land was randomly chosen for testing in both the Danby Woodlot and Danby Grassland at York University. A transect was randomly placed at both habitat types and pulled in a straight line until the transect read 10m. Nine coloured plastic solo bowls were positioned at every meter of the transect. The pan traps laid 1m a part in a line of nine in each testing site; making 18 pan traps in total. The bowls were strategically placed in both the woodlot and grassland with an alternating pattern of yellow, light blue, dark blue, and white. Each bowl was filled approximately half way with soapy water and left untouched for 1.5 hours. After 1.5 hours each pan trap was individually observed. The total number of insects found in the soapy water of each bowl was counted by sight and recorded. The same abundance of insects was then examined for recognizable taxonomic units. Any insect with morphological characteristics unique to the other insects in the bowl was considered its own taxonomic unit. The number of different taxonomic units was recorded for each pan trap. After each trap was examined the soapy water was discarded onto the ground and the living insects were released back into the environment.

元数据：颜色
指沿地面布设、彼此间距1米的单只碗状诱虫器（pan trap）所用塑料碗的颜色。本次布设的诱虫器采用黄、浅蓝、深蓝、白的交替配色方案。诱虫器颜色通过肉眼两两比对进行判定。

生境类型：
指碗状诱虫器的布设生境。本次诱虫器分别布设于以“林地（woodlot）”为指代的丹比林地（Danby Woodlot）深处，以及林地旁以“草地（grassland）”为指代的草地。生境通过目视树木分布判定：林木、枝叶繁茂的封闭区域为林地，开阔且生长高大植株的区域为草地。

个体丰度：
指单只碗状诱虫器布设1小时后，其内皂液中可见昆虫的总数量。通过目视计数所有具有可识别昆虫形态的个体，未处于皂液中的个体不计入统计。本次使用的所有诱虫碗尺寸一致，且盛装的皂液体积基本相等。

可识别分类单元数（RTU）：
指单只碗状诱虫器内的不同可识别分类单元（Recognizable Taxonomic Unit, RTU）数量。凡具有与诱虫器内其他昆虫显著独特形态特征的昆虫，均视为独立的分类单元。通过目视计数分类单元数量，未处于皂液中的个体不计入统计。本次使用的所有诱虫碗尺寸一致，且盛装的皂液体积基本相等。

数据采集背景：
本次数据采集于约克大学（York University）校外的丹比林地与丹比草地，时间为9月的某周三下午4点15分左右。当日天气为中等晴朗，风速适中，气温18摄氏度。丹比林地区域遮阴度高，林木与植被茂密，地面覆盖有枯枝、落叶、枝条及人类废弃物。丹比草地区域开阔，生长着大量高约1米的草本植物与花卉。本次采样由18名约克大学学生与1名助教在两类生境中完成，采集不同类型的样本。

研究假设：
本研究假设，碗状诱虫器的颜色与布设位置均会影响特定区域内捕获的昆虫数量与种类多样性，因为不同昆虫类群可能对特定生境或颜色存在偏好。

研究预测：
本研究预测，黄色与白色诱虫碗的昆虫个体丰度与分类单元多样性将高于其他颜色，因为这两种颜色与常见花卉颜色相近，可吸引更多不同分类单元的昆虫。同时预测丹比林地的昆虫个体丰度与分类单元多样性更高，因为区域内大量树木可为多种昆虫提供营养与栖息场所。

材料与方法：
本研究在约克大学的丹比林地与丹比草地中，各随机选取一条10米长的样带。在两类生境中均随机布设样带，沿直线拉伸至10米长度。在样带的每1米位置处放置1只彩色塑料一次性餐碗，每个样带共布设9只诱虫器，两类生境总计18只。诱虫碗采用黄、浅蓝、深蓝、白的交替配色方案，分别布设于林地与草地中。每只碗盛装约半满的皂液，静置1.5小时后逐一观测。通过目视计数每只碗内皂液中的昆虫总数量并记录。随后针对该样本中的昆虫统计可识别分类单元：凡具有与碗内其他昆虫独特形态特征的昆虫，均视为独立分类单元，并记录每只诱虫器的不同分类单元数量。观测完成后，将皂液倾倒至地面，将存活昆虫放回原生存环境。