Studying the Diversity and Interactions of Plant Species in a Grassland Using a Quadrat

Group Members: Loyal Tran, Anisa Amin, James Quach, Iiman Darman Four datasets were to be collected during this lab. The group was split into two as to save time; this dataset (dataset 1) was collected with Loyal Tran. The data was collected on a grassland next to the Danby Woodlot at York University on September 23, 2015 from 15:00-16:15. The equipment used to collect this data was a 1-meter x 1-meter quadrat. 20 samples were collected by placing the quadrat in 20 completely random areas around the grassland. The samples were 1 labelled through 20 in the order in which the data was collected. The weather that day was 23 degrees Celsius with minimal breeze making it quite hot. It was very sunny as the sky was clear. Although there were several species of plants in the grassland, they were not distributed evenly across the grassland, instead majority of the plants were clustered with members of the same species in relatively smaller areas. However, in some areas, these clusters overlapped. Total abundance, species abundance, percent covered, and grass coverage were measured within each quadrat. Total abundance was defined as the total number of plants and was determined by counting the number of individual plants that could be seen in a single quadrat. Species abundance was defined as the total number of different species of plants and was determined by counting the number of different species that could be identified in a single quadrat. Species were differentiated based on the characteristics of their leaves (i.e. shape, number of blades, thorns, spines, prickles) and the colour of their flowers. Percent covered was defined as the total area that the plants covered on the soil relative to the total area of the quadrat. It determined by visually estimating what percentage of the quadrat it the plants covered. Total grass coverage was the total area inside the quadrat that was covered by grass. Grass coverage was visually estimated. In this experiment, grass was not included when measuring the total abundance, species abundance, or percent covered because it was common amongst all sample and was accounted for in grass coverage. Furthermore, estimating the total abundance of grass would have been very difficult. Since majority of this experiment was done mainly based on visual observations, the chances of errors in the data are high. Species of plants could have been misidentified, smaller plants may have been overlooked while calculating total abundance, and the estimation of percent covered and grass coverage may have been slightly imprecise. Moreover, this data could have been subject to the sample of convenience bias.