Assessing Lower Canopy – Lab Report Example
Assessing lower canopy, LOD attributes Assessing lower canopy, LOD attributes Objectives To gain experience in the application oftwo transect sampling techniques.
Point transect sampling for lower canopy vegetation and,
Line intersect sampling for volume or biomass of dead material.
2) To gain experience in the application of fixed-area plot sampling for these same attributes.
3) To gain familiarity with variability of lower canopy assessment data and the magnitude of possible measurement errors
Canopy is the upper layers of a forests population usually formed by tree crowns and may also include other organisms such as epiphytes and lianas. A canopy can be several layers thick depending on the type of forest, for example, a rain forest canopy is about ten meters thick (Campbell & Norman, 1990). The layers of a canopy usually are made up of the different tree species with different heights with the tallest trees forming the outermost layer of the canopy and the other trees following according to their heights (Moffett, 2000). The photosynthesis of trees in a forest with a canopy is usually limited for the lower layers due to the lack of sufficient light to facilitate the process (Hay & Porter, 2006). This reason tends to make the bottom layer vegetation to be weak compared to the dominant population of trees.
Point transect method
25 points were placed along a 100 feet length every 4 feet apart starting from foot 1.
At each point, a vertical projection was done up to 10 feet and the species of any non-tree vegetation that intercepted the projection recorded.
Line intercept method
Lanes about 4.6 inches in diameter along 100 feet transect were used to evaluate the amount of LOD
For logs the diameter of the part where it crosses the line was measured while for stamps the diameter at a height of 1 foot above the ground was measured and recorded.
Fixed- area plot sampling
A plot center was established at the 50 feet mark along the transect.
The cover for lower canopy vegetation was measured using a small plot (1/100th acre) and recorded to the nearest 5%.
The LOD analysis was done on a large plot (1/10th acre), and the diameter at the end of each LOD recorded and the length of the log within the plot recorded also.
Transect Vegetation (%cover)
Sword Fern 21.8%, Moss 37.5% and Salmonberry 25%
Sword fern 24%, Salmonberry 24% and Trailing Blackberry 28%
Stinging nettle 26.5%, Salmonberry 18.4%, Trailing Blackberry 12.2%
Sword Fern 52%, Salmon Berry 44% and Red Flowering Currant 16%
Salal 10%, Salmonberry 10% and Sword Ferm 5%
Fixed Plot Vegetation (%cover)
Swordfern: 30%, Salmonberry: 40% and Indian plum: 30%
Sword fern 35%, Trailing Blackberry 15% and Cleaver Plant 10%
Stinging nettle 25%, Salmonberry 55% and SwordFern 15%
Sword Fern 35%, Red Flowering Currant 20% and Indian Plum, 20%
Stinging Nettle 20%, Salmon Berry 20% and Salal 10%
Transect LOD (ft3/acre)
V = 5644.65 cubic ft. /acre
V = 157.667 cubic ft. /acre
V = 22,473.21 cubic ft. /ac
V = 37349.86197 Cubic ft. /acre
V = 1397.447 cubic ft. /acre
V = 215.56 cubic ft. /acre
Fixed Plot LOD (ft3/acre)
V=256.52 Cubic ft. /acre
V = 14.67 Cubic ft. /acre
V = 48416.02 Cubic ft. /ac
V = 86.548 cubic ft. /acre
V = 945.129 Cubic ft. /acre
V = 78.23 cubic ft. /acre
Discussion of results and conclusion
From the experimental data and its analysis, there has been a thorough investigation of the canopies within the ecosystem in the environment where the experiment was. The different methods of data collection collected their individual set of data of a particular canopy and the data was analyzed to find out the percentage of various tree species in the specific canopies depending on the region where it was collected from. From the data, it was also able for the students to learn the different tree species in that particular forest. The three methods of data collection and analysis were utilized, therefore, the students gained excellent skills in the use of the three methods.
The experiment can be concluded to have been successful since all the objectives were achieved and the data obtained had a high accuracy level. The students gained enough experience to participate in such practical sessions in the future.
Campbell, G.S., & J.M. Norman. 1990. The description and measurement of plant canopy structure. pp. 1-19 In: Russell, G., B. Marshall, and P.G. Jarvis (editors). Plant Canopies: Their Growth, Form and Function. Cambridge University Press.
Moffett, M.W. 2000. Whats up? A critical look at the basic terms of canopy biology. Biotropica 569-596
Hay, R., and R. Porter. 2006. Physiology of Crop Yield. New York: Wiley-Blackwell Parker,