Lab 4: The Effects of Grassland and Woodlot Ecosystems and Edge Effects on Plant Abundance

This experiment took place at York University Keele Campus, Danby woodlot and grassland area on October 15th 2015 (week 1) and October 22nd 2015 (week 2), between 2:40pm to 4pm. The weather conditions in week 1 were: 17 degrees Celsius, cloudy with light rain, wind speed of 26 km/h from the South-West, humidity 37%, and visibility was 16 km. The weather conditions in week 2 were: 16 degrees Celsius, sunny with some clouds, wind speed of 25 km/h from the North-West, humidity 46%, and visibility level was 16 km. The experiment was done by group 1 members, Greg P, Albert Lin, Gajamugan Rajavarothayan, and Hannan Fayyaz. The purpose of this experiment was to determine if plant abundance was affected by edge-effects (position from edge to center), and by the different environments of the Danby woodlot versus the adjacent grassland area. Plant abundance data was collected in both locations (woodlot and grassland) on two separate days one week apart, by placing 1m x 1m quadrats incrementally along one side of the transect measure starting at 0m, in each corner of the location, and moving into the center of that location in 5m increments for a total of 10 replicates per corner. Plant abundance data for each location was visually observed in each quadrat and the position on the transect from 0m to 45m was recorded each week. This was repeated in week 2, except the quadrat was placed on the opposite side of the transect from the previous week. This totals 40 replicates per location and 160 replicates in total after 2 weeks. Each group member collected data from one corner in both weeks. Gajamugan collected from the North-West corner, Greg collected from the North-East corner, Albert collected from the South-West corner, and Hannan collected from the South-East corner. Grass in the grassland area were too numerous to count by hand, so estimates were taken by counting a small area in the quadrat and multiplying to get the estimated total area. Large plants were counted separately and added to this estimate. The grass estimates were too high, so the last digit in any four digit count was dropped, and then large plant count was added to get the total observed abundance. There were no problems collecting data in the grassland area, other than correcting for large estimates. In the woodlot sampling estimates may have been skewed by difficultly placing the quadrat down on uneven ground. There were plenty of dead logs and large trees that needed to be avoided in order to place quadrats down. The observer’s best judgement was used when obstacles prevented accurate quadrat placement. Moss was also observed in the woodlot but not the grassland, although it was not counted in abundance due to difficultly in quantifying it. There was a homeless person in the south-east and north-east path of the woodlot location, so distance from edge to center may have veered off course to avoid this person. Finally, the woodlot had many tall trees, so there was no clear line of vision to the center, only the observers best estimate towards the center was used in determining where to place the transect. General observations for grassland included there was much more grass, and only one tree in the path of the transect. In the woodlot there were many trees, a lot of shade, few grass, some moss and many dead plants covering the ground, and the ground seemed more moist than the grassland. Dead plants were not counted in abundance. The observer's best judgement was used in determining which plants were alive and dead. All data recorded was from visual observation.