User: | Open Learning Faculty Member:
My field data collection went well overall. I sampled 10 deciduous and 10 coniferous trees on each of my two transects for a total of 40 trees sampled. I sampled the first transect on February 26th and the second on February 28th, they each took roughly 2 hours. I did them separately because I have a knee injury so I’m trying not to over exert myself. I had originally planned to do my first transect on the Glendenning trail in the southern part of Mount Douglas Park, and the second transect on the Whittaker trail in the northern part. The first transect went smoothly, but when I went to do the second transect on February 27th, I realized that the northern part of the park was quite different than the southern part in that it was much more hilly and rocky, the understory shrub layer was dense which made it really difficult to move around in, and the deciduous trees were mostly arbutus which tend to have bent trunks not suitable for my sampling design. I checked some of the other trails on the north side of the park but they were all similar so I decided I would do my second transect in the southern part, as a continuation of my first transect on the Glendenning trail. I should have done site reconnaissance beforehand, I assumed that because the north and south were both in the “lower forest” designation that they would have been similar sites, but nope! It would have been interesting to sample the northern part because just from a quick observation I could tell there was higher lichen diversity and a different community composition.
Things I noticed/experienced:
The frequency of deciduous trees was much lower than coniferous trees, so when I would arrive at my random point and sample the closest tree to me, sometimes there wasn’t a deciduous tree close by so I would just sample the two closest at the next possible point. Not a big inconvenience and didn’t effect the randomization.
I noticed that further up the trunks of the trees I sampled, or sometimes at the base of trees, there appeared to be higher lichen richness and abundance especially of the foliose and fruticose type. My study design focused solely on the 1 metre area that is 1.5 metres off the ground, excluding higher on the trunk and the canopy of trees. On the ground surrounding the trees there was often litter from the canopy which can give an idea of what lichens are growing up there, but I didn’t look at that for my study because it would have been too complicated.
On the larger trees sometimes the bark was so deeply and widely furrowed and lichens tended not to grow in the furrow, but on the ridges of the furrow. Due to the fact my transect was quite narrow, 10x100cm, sometimes the bare furrow would be right at the cardinal direction of the tree and I would have to put 0% coverage or a low% coverage which didn’t seem appropriate because there was high lichen coverage right beside. Perhaps having a wider quadrat and standardizing the tree size would be a way around this.
All in all, I deepened my appreciation for how much preparation and fine-tuning it takes to develop appropriate sampling designs and actually carry them out in the field.
