yorku.grassland.disturbed.October4.2016.csv

The purpose of this lab was to identify the abundance of plants, trees, vertebrates and invertebrates in grassland and disturbed habitats. The data for this experiment was collected from the grassland and disturbed area lot located at York University Keele Campus (43.7 degrees North, 75.9 degrees West), between York Blvd and Keele St. at 3:15 pm. It was 21°C and partly sunny and cloudy. Four different experiments were conducted in each habitat - the grassland and disturbed area (categorical). It took 90 minutes to collect all of the data for all experiments.In the first experiment the quadrat was used to observe the abundance of native plants, exotic plants, and the total number of plants in the grassland and disturbed area which were recorded as continuous data. Two 30m transect tapes were used to measure a transect line of 50 meters. The quadrat was placed on the left and right side of the tape to measure the abundance of plants and total number of flowers. When counting the abundance of plants in the disturbed area, the quadrat was divided into 16 squares and the total number of grass on each square was multiplied with 16 to acquire the total number of grass on the whole quadrat. The habitats used in this experiment were recorded as categorical and abundance of plants found were continuous. In the grassland, the native plants were observed and counted in the entire quadrat. The trial was repeated 25 times for each habitat therefore, a total of 50 meter square area was observed. Flower heads were also observed and counted in the same way for both areas. It was hypothesized that higher abundance of plants and flower heads will be observed in grassland. The prediction was made since the grassland has more insects, increasing the pollination rate and more sunlight for higher plant growth. The second experiment was done to collect data about woody plants in the grassland and disturbed area. Using transect tape, a straight line of 50 meters was measured along the grassland. The abundance of woody plants (trees greater than 1.5 meters tall) was observed and recorded for every 2 meters along the transect line. Every other meter along the transect, the percentage of canopy coverage and ground coverage were estimated based on observation and the continuous data was recorded. In addition, the total number of plants were observed every 5 meters along the transect and numerically recorded. A total of 25 replicates were recorded for each continuous variable. The same method was also used to measure the abundance of woody plants and the total number of flowers, measure canopy coverage and ground coverage in the disturbed area. It was hypothesized that the disturbed area would have a greater abundance of woody plants than the grassland because the disturbed area is beside a forest. In addition, the grassland would have a greater number of flowers than the disturbed area of the greater diversity found in grassland.For experiment three, a transect measured to be 50 metres was placed on the disturbed open space. The surroundings were then observed to for fifteen minutes to observe the abundance of vertebrates, the number of species of vertebrates, and the abundance of humans who were not part of BIOL2050. In the grassland area, the same method was carried out for this habitat. The second half of the experiment involved placing a 5 metre transect on the disturbed open space, and measuring the abundance of invertebrates in the 5 metre radius for fifteen minutes. The same method was carried out in the grassland to measure the abundance of invertebrates. It was hypothesized that the abundance of invertebrates and vertebrates would be greater in the grassland than the disturbed open space. It was predicted that invertebrates and vertebrates would be more abundant in the grassland area because the habitat was better suited for their survival. More disturbed areas are destroyed by human interference with their environment.In the fourth experiment which used the pan trap method and sweeping nets, 6 bowls were randomly placed 3 metres apart from each other in both the grassland and disturbed area. Each bowl was completely filled with soapy water and the abundance of invertebrates were observed and recorded by counting the total number of invertebrates found in each bowl an hour later. Thus, there were a total of 12 replications. The second half of the experiment involved placing a 50 metre transect in both the grassland and disturbed open area using transect tape. Using the sweeping net, the abundance of invertebrates were observed and recorded for each habitat (grassland and disturbed area) after walking down the 50 metre transect 10 times, for a total of 20 replications for the sweeping net experiment.The abundance of invertebrates were recorded as continuous data. It was hypothesized that the abundance of invertebrates would be greater in grassland than the disturbed area. This meant that it was expected that more invertebrates would be observed in the grassland due less disturbances in the grassland leading to more interactions between plants and invertebrates.

本实验的研究目的为调查草原与受干扰生境中植物、乔木、脊椎动物与无脊椎动物的丰度。实验数据采集于约克大学基尔校区（York University Keele Campus，北纬43.7°，西经75.9°）内位于约克大道（York Blvd）与基尔街（Keele St）之间的草原及受干扰区域，采集时间为当日15:15，气温21℃，天气为晴间多云。本研究在两类生境（草原与受干扰区域，均为分类变量）中各开展4组实验，全部数据采集总耗时90分钟。

实验一：利用样方（quadrat）观测草原与受干扰区域内本土植物、外来植物的丰度及植物总数量，数据以连续型变量记录。实验使用2卷30米长的样带尺（transect tape）布设50米长的样带，将样方放置于样带两侧，以测量植物丰度及花朵总数量。在统计受干扰区域的植物丰度时，将样方划分为16个小方格，统计每个方格内的草本植物数量后乘以16，即可得到整个样方内的草本植物总数量。本实验的生境类型为分类变量，所测得的植物丰度为连续变量。在草原生境中，对整个样方内的本土植物进行观测计数。每个生境的实验重复25次，总计观测面积为50平方米。两类区域的头状花序均采用相同方法进行观测计数。本研究提出假设：草原生境中的植物及头状花序丰度更高，作出该假设的依据为：草原生境中昆虫更多，可提升授粉效率，且光照更充足，更利于植物生长。

实验二：采集草原与受干扰区域内木本植物（woody plants，即高度大于1.5米的乔木）相关数据。沿草原布设一条50米长的直线样带，沿样带每间隔2米观测并记录木本植物的丰度；沿样带每间隔1米，基于观测估算冠层覆盖率与地面覆盖率，并记录为连续型数据；此外沿样带每间隔5米观测并记录植物总数量。每个连续变量共计记录25次重复。在受干扰区域中，采用相同方法测定木本植物丰度、花朵总数量、冠层覆盖率及地面覆盖率。本研究提出假设：受干扰区域的木本植物丰度高于草原生境，因该区域紧邻森林；同时预测草原生境的花朵数量多于受干扰区域，因草原生境的生物多样性更高。

实验三：在受干扰开阔区域布设一条50米长的样带，随后对周边环境开展15分钟的观测，记录脊椎动物丰度、脊椎动物物种数，以及非BIOL2050课程参与者的人类个体丰度。在草原生境中采用相同方法开展实验。实验后半段，在受干扰开阔区域布设一条5米长的样带，于5米半径范围内观测无脊椎动物丰度，时长15分钟；在草原生境中采用相同方法测定无脊椎动物丰度。本研究提出假设：草原生境中的无脊椎动物与脊椎动物丰度均高于受干扰开阔区域，预测依据为：草原生境更适宜二者生存，而受干扰区域因人类活动干扰更为严重，生境破坏程度更高。

实验四：采用泛陷阱法（pan trap method）与扫网法开展实验。在草原与受干扰区域内，随机放置6个间距为3米的容器，每个容器均装满肥皂水，1小时后观测并记录每个容器内的无脊椎动物丰度，总计完成12次重复。实验后半段，在草原与受干扰开阔区域内布设50米长的样带，使用扫网沿50米样带行走10次，观测并记录每个生境的无脊椎动物丰度，扫网实验总计完成20次重复。无脊椎动物丰度以连续型变量记录。本研究提出假设：草原生境中的无脊椎动物丰度高于受干扰区域，因草原生境受干扰程度更低，植物与无脊椎动物间的相互作用更为频繁，因此可观测到更多无脊椎动物。