My initial field data was measuring the diameters of sagebrush (Artemisia tridentata) along an elevation gradient. I had hypothesized that sagebrush diameters decreased as elevation increased and so far the data does not seem to falsify this. The data I have collected is not surprising. My sampling strategy was systematic sampling as I had to follow the elevation gradient up along certain paths that were suitable for walking on. The only minor difficulty I had was the elevation measuring app I had on my phone did not seem extremely accurate so I had to confirm the elevations on a computer program afterwards. Now that I know the proper elevations for the park it will be easier to continue sampling the rest of my data.
The results of the three area based sampling strategies used in the virtual forest tutorial are summarized below.
Systematic Sampling (12 hours, 7 minutes):
Most Common Species
Data Densities
Actual Densities
% Error
Eastern Hemlock
504.2
469.9
7.3
Sweet Birch
112.5
117.5
-4.3
Rarest Species
Chestnut Oak
66.7
87.5
-23.8
Red Maple
137.5
118.9
15.6
Random Sampling (12 hours, 42 minutes):
Most Common Species
Data Densities
Actual Densities
% Error
Eastern Hemlock
504.2
469.9
7.3
Sweet Birch
137.5
117.5
17
Rarest Species
Striped Maple
41.7
17.5
138.3
White Pine
20.8
8.4
147.6
Haphazard (12 hours, 59 minutes):
Most Common Species
Data Densities
Actual Densities
% Error
Eastern Hemlock
540
469.9
14.9
Sweet Birch
108
117.5
-8.1
Rarest Species
Red Maple
41.7
118.9
-64.9
Striped Maple
8
17.5
-54.3
Systematic sampling was the most accurate for both common and rare species. % error was quite higher for the rarer species for all three methods.
The most efficient technique timewise was systematic, followed by random, followed by haphazard. The time differences weren’t’ too dramatic, with a spread of only 52 minutes between the most and least efficient.
Considering how close to the actual data the sample was in the systematic method, it would seem to be a sufficient sample size to have a solid understanding of the species numbers and abundance of the common species. However, the rarer species would seem to require further sampling to get more representative data.
B) The paper is academic peer-reviewed research material.
C) The paper is academic peer-reviewed research material since there is a method section in which they collected 127 wasps. Also, the paper contains a results section discussing what they found in the field.
For my field research project, I will be observing Cates Park in North Vancouver, B.C. This park is a district ran park and covers over 22 hectares of land along the Burrard Inlet. The park is mainly flat along the ocean and contains a large forest area with many trails running through the park. The park also contains large grassy areas and a large beach running along the ocean. The vegetation in the park contains mostly Douglas fir and maple trees along with ferns and other forms of vegetation. I visited the park on November 6, 2017 and the temperature outside was six degrees Celsius with very little wind and sunny. I noticed that animals in the area were far more scarce compared to mid summer. This is most likely due to the cold weather we have been experiencing in the area. For my project I may focus on how the vegetation adapts to the colder weather. Also, I will focus on the animals that are still present in the park and what they feed on. My project will mainly focus on the adaptions and constraints for animals and plants that are associated with Cates park.
In the virtual forest sampling simulator the random sampling was significantly faster than systematic and haphazard sampling.
Systematic – 12 hours, 35 minutes
Random – 4 hours, 24 minutes
Haphazard – 12 hours, 30 minutes
Common Species
Rare Species
Sampling Technique
% error
Eastern Hemlock
Sweet Birch
Striped Maple
White Pine
Systematic
17.2%
30.0%
126.8%
138.1%
Random
16.6
28.2%
100.0%
25.0%
Haphazard
8.2%
31.2%
18.9%
99.0%
In comparing the percent error of the three sampling techniques with the exception of white pine in the random sampling, the percent error increased with decreasing species abundance. Based on this sampling simulator, the haphazard sampling technique is the most accurate. Although, it should be noted that the random sampling technique had similar percent error values. Systematic sampling had notably higher percent errors for species with low abundances.
My initial data collection for Module 3 involved taking systematic quadrant samples of native & invasive alien plant communities within two separate locations. Using the multiple transect sampling technique, ten quadrants were laid out along each transect, roughly 5 meters apart. Each quadrant sampled was 1m/square in size, using a homemade PCV pipe observation quadrat device. The first sample location site (Site A) was taken along an of leash dog area; A coastal bluff which was comprised of mostly degraded bare soil & rocky outcrop, also greatly worn due to human & canine traffic. The second sample location site (Site B) was an area that is *supposed to be* off limits to canine & human traffic. I found that this was clearly not the case, as human & canine activity is often observed in these no access areas & unfortunately, I suspect my results were skewed due to this. This location was in the same park as my first site, although the samples were taken approximately 100 feet away from the first site throughout a sloping wetland, lush marsh / meadow. The park contains pubic info boards which describe that it contains SARA plant populations (Federal Species at Risk Act) & to obey the signage which clearly indicates out of bound locations.
I did have some difficulties when implementing sampling strategies for my second sampling site (Site B), in the marshland / meadow transect sample areas. I did not want to tread on a location that was “out of bounds” to the public, so I leaned over the fence (which is only about 3 ft high) & floated my sample device over top of the sample area, recording my observations as I went along the transect. The first sample site was much easier (Site A), as I could actually place my sample device on the ground, making it much easier to observe, write down my observations, & even take pictures when necessary.
The data collected at Site B was quite surprising to me. I expected to find a greater diversity and density of plant species observed, due to the fact that this area was restricted. Unfortunately I found that most people (including a few mountain bikers!) did not observe the areas that contained SARA species & were clearly marked as out of bounds. My low plant counts in Site B reflected this. Site A is a well used, high foot traffic area, so I did expect the plant species & density to be a bit lower than Site B. I was not expecting that my results would show the density & diversity to be as similar in numbers as it turned out to be.
With regard to collecting data, & for the sake of my field research project, I will modify my approach slightly. I will still use the sampling device I made & method used, but I will observe my samples in different areas that what was chosen for Module 3. I will expand my transect line & quadrats out by a few more meters between each sample. I am hopeful that these modifications will improve my research. My explanatory variable – I will observe plant composition communities along a drier & more exposed coastal bluff in one site, vs. plant composition communities observed in a higher elevation site with a different overstory (meadow). I will be looking to observe plant composition community differences between site A (bluff) and site B (meadow).
The organism I would like to study is Douglas Maple (Acer glabrum). More specifically, variation in its abundance along a spatial gradient from a mature Western Cedar (Thuja plicata).
For initial observations compass bearings of 20°, 40°, and 60° were taken from the base of the T. plicata. Along each of these bearings, plot centers were established at 5, 10, and 15 m. Each plot was 1m2 and the number of A. glabum within each was recorded, as shown in the table below.
Distance from T. Plicata in m
# of A. glabrum along 20° bearing
# of A. glabrum along 40° bearing
# of A. glabrum along 60° bearing
5
0
0
0
10
3
8
4
15
5
2
6
During the time observations were taken, the entire plot site that was <5m from T. Plicata was in the shade and the 5-10m part of the site was in full sun.
The entire site is located on west facing hill that is has a 12% slope.
I did the above observations before watching the study design videos and I now know that what I did is a systematic sampling method. Upon further reflection, and after watching all the vids, I’m thinking it makes more sense to do a random sample method as explained by Lyn Baldwin. So, I did a second sample methodology using an app to generate random compass bearings and paces to locate 1×1 m plots in 10 different locations within the site. The following was observed using this method:
Paces from base of T. Plicata
Compass bearing (°)
Number of A. Glabrum in plot
2
35
0
5
34
0
3
22
0
6
92
0
15
19
5
11
88
2
3
42
0
5
84
0
0
57
0
6
79
0
Some processes that may be causing the variation in species abundance is the shade from the large conifer, differences in soil moisture content, differences in mineral composition, or distance from the conifer. However, my main hypothesis is that the shade created by the T. plicata reduces the stand density of A. glabrum by reducing the availability of incoming solar radiation. To help test this hypothesis, observations will be made as to how much sunlight and shade the site is in throughout the day.
The response variable is A.glabrum and all of the processes listed above are predictor variables. The response variable is continuous as it is being quantified by counting and the predictor variables are all continuous. Therefore, I infer that this is a regression experimental design and inductive methods will be utilized to test my hypothesis since initial observations of reduction in stand density as distance from the conifer increases will try to be explained.
I have selected for this post a journal article from researchers at the Nereus Program, an interdisciplinary ocean research partnership based out of UBC:
http://www.sciencedirect.com/science/article/pii/S0308597X17301409
Rebecca G. Asch, William W.L. Cheung, Gabriel Reygondeau, Future marine ecosystem drivers, biodiversity, and fisheries maximum catch potential in Pacific Island countries and territories under climate change, In Marine Policy, 2017, ISSN 0308-597X, https://doi.org/10.1016/j.marpol.2017.08.015.
The authors of this paper all hold PhDs in ecology-related fields and are oceans researchers at major universities (in addition to the info in the article byline, their academic history is available here: http://www.nereusprogram.org/about/fellows/). The paper is chock-full of citations and has a bibliography. Therefore, I can safely conclude that this is an academic document.
This paper was published in Marine Policy. On inspection of the journal’s website, they employ double-blind peer review.
The authors include sections on their methods and results, which indicates that this is research-based. The entire paper went way over my head, and threw around words like “synthesize” and “overview”, so I may well be wrong.
South Entrance (roundabout): 50°06’14.9″N 120°45’54.0″W
I chose to study a field near my home in Merritt. On this particular trip, I stuck to the east side of the main path, marked in yellow. I went on October 30th from about 2-4pm. It was a clear, sunny day (no clouds whatsoever). It has since snowed heavily, so this field will be a puddle next time I visit.
The entire field is flat, roughly 500m^2, and surrounded to the south and west by housing, to the east by the main road into town. There are a few human-made paths, visible in the map. The only animal signs I found were dog scat and bird calls, and I encountered no insects. The soil is moist and seems to be clay. There was quite a bit of litter at the human entrances, and housing construction at the west entrance.
The field is dominated by a long, yellow grass growing in bunches, with spiky pods (?) at the tips (which will probably take a month to remove from my socks). There are a few sparse coniferous trees and other plants in localized areas. These included:
A localized, 15m^2 patch of a wheat-like grass and burrs in the north (just northeast of the tree by the path)
Moss under the main grass in the southeast
A dead or dying leafy plant interspersed sparsely in the main grass
Red thornbushes on the slope up the the highway
Some reddish low plants (called “underbrush” in my notes) on a small northern section of the main path
A plant which resembled to me a round hairbrush along the edge of the northern section of the path
Possible Questions
What are human impacts on the area (e.g. walking paths, recent construction, pollution) and how do they affect the local plantlife?
What differentiates the small areas where the yellow grass does not grow as much from the rest of the field
What are common factors (e.g. sunlight, slope, types of soil, etc) in areas where this yellow grass grows throughout the Nicola Valley?
Journal Pages
Additional Photos
The main yellow grass dominating the field.
Example of the “bunches” the yellow grass grows in.
Thornbushes growing on the slope to the highway
Example of the “bunches” the yellow grass grows in.
“Hairbrush” plant, found on north part of path.
“Underbrush”, found on north part of path.
Detail of “underbrush” plant.
Red berries found on thorn bushes near highway.
Burrs in wheaty stretch, referred to in journal as “thistle”.
The site where I will carry out my research project is located at 1823 Creek Street in Nelson, BC, in the NE corner of the property. This property is on what was originally a large forested slope. UTM: 11U479004mE 5480823mN. ASL: 153.
Site was visited on 14-11-2017 at 1245 PST. Weather was overcast and 5 degrees celsius.
The size of the site is approximately 10m x 6m. It is on a west facing slope with a 12% gradient.
The species composition are dominated by the following:
A layer:
mature Thuja Plicata approximately 1.5 m diameter
dead standing Prunus Virginia
Acer glabrum
B layer:
Acer glabrum
Salix spp.
Sorbus sitchensis
Sambucus spp.
C layer:
Symphoricarpus albus
Mahonia aquifolium
Unidentified invasive groundcover (dominates)
There is also some moss present on the large boulders that are found in the site. The ground is blanketed in dead maple leaves and cedar debris. Two fresh piles of deer scat were observed. This semi-rural backyard greenbelt has some signs of anthropogenic activity including a small shed, trimmed tree branches, and invasive species.
Since there is good spatial variation within the site, it seems to provide a good opportunity to make some comparisons between the different types of areas, focusing on potential variations in ecosystem properties between areas dominated by coniferous, and those dominated by deciduous. 3 potential research questions:
Snow accumulation in various locations throughout the site.
Differences in LFH layers throughout the site.
Differences in mineral properties throughout the site.
