My study location is an open field that has a walking trail (linear disturbance) running through it. Upon walking along the trail on my first site visit I noticed that there were many non-native species present along the trail. With further observation, it appeared to me that many of these non-native species are more abundant closer to the trail than at greater distances.
I decided to study the spatial distribution of two non-native species (corn gromwell and sulphur cinquefoil) in relation to the trail. These species were chosen as they are easy to identify. My hypothesis was that if an area is closer to a linear disturbance then it will have a higher abundance of non-native species (i.e., a higher abundance of the two non-native species being measured). To test this hypothesis I used a systematic design. Transects were set up every 2 m perpendicular to the trail, with the transect being placed on alternating sides of the trail to increase independence (i.e., a transect on one side of the trail would be 4 m from the next). Additionally, as the field is sloped (with the trail running through the middle of the field) I thought that setting up transects on both sides (going both upslope from the trail and downslope from the trail) would mitigate getting results that are actually due to differences in elevation or moisture instead of due to distance from the linear disturbance. Along the left side of each transect I set up a 1 x 0.5 m quadrat at 0 m (the edge of the trail), 5 m, 10 m, and 15 m. In total I measured 6 transects, with 3 being on each side of the trail, thus giving me 6 replicated of abundance measurements at each distance from the trail. Abundance was measured by estimating percent cover in each quadrat for each species individually, so that data for each species could be analyzed separately.
I did find it hard to estimate the percent cover due to the size of the quadrat; however, I think decreasing the size of the quadrat would make it more difficult to see a pattern in distribution of the corn gromwell and sulphur cinquefoil as there was often a lot of space between each patch of the plant. Another result I was not anticipating was that as the sulphur cinquefoil tended to grow in clumps, it was often not present in the quadrat even though it was present at that distance to the left or right of the quadrat placement. To combat this, a larger number of replicates will be taken.