Discussion
Part 1:
In the first part of this project which was to compare two different methods for creating a map showing a specific feature, it appears as if both methods give similar results.
In Figure 1 which looks at Basal Area both maps show a high basal area in the South West corner as well as low basal area along the North edge. Figure 2 shows that both different methods produce similar maps for the height of dominant trees, the forest is taller in the south side of Stanley Park and the forest is much shorter in the North Eastern side. In Figure 3 the IDW map shows that there is lots of variation in the number of germinants and lots of small circles where the germinants is high. However both maps show lots of germinants along the south side.
The most likely reason for the low basal area and stand height in the North area of Stanley park is likely because that is where the 2006 windstorm did the most damage (Vancouver Board of Parks and Recreation, 2003).
Both of these methods produce similar results for mapping the same feature, this shows that it probably does not matter which method is used to create a map showing one feature.
Further analysis could be used to compare the maps that were produced to the actual numbers measured and to see if the value measured is similar to what the map shows. For the IDW method the search radius used 12 different points to calculate the value at a certain area with nearer points being more important. A different result would have been found if a different number of points were used.
Part 2:
The results for the second part of this project show that none of the factors that were looked at predict the amount of tree regeneration. For all of site series, basal area, and stand height the R2 values were very close to 0 and the F-prob values were not significant.
A major reason that the results showed no connection between the factors and seedling growth is that different tree species grow in different conditions. For example western red cedar grows better than Douglas fir at low light levels (Carter and Klinka, 1992). Basal area may have affected light levels reaching the forest floor so it may have an effect on specific species. Carter and Klinka also found that soil moisture when combined with light affects tree growth (1992). A multiple regression analysis could have been done to see if both of these factors combined influence the amount of seedlings.
Further research could be done separating tree species or by combining factors.
Works Cited:
Carter, R.E., and Klinka, K. 1992. Variation in shade tolerance of Douglas fir, western hemlock, and western red cedar in Coastal British Columbia. Forest Ecology Management, 55, 87-105.
Vancouver Board of Parks and Recreation. 2003. Stanley Park Public Access. http://vancouver.ca/parks/info/features/2007/070129_SPopen_closed_areas.htm