Reference no: EM132409878

BIOL 4312 Analysis of Biological Communities Assignment - University of Manitoba, Canada

Part A - Correspondence Analysis: Bovid Tribes In Africa

Using the correspondence analysis (CA) ordination (axes 1 versus 2) as your guide (Figure 1), summarize the major trends in the bovid tribe density data by answering the following questions:

1. Summarize and discuss the relative configuration of the nine (9) Bovid Herbivore Tribes. Provide specific examples to support your summarization and discussion.

2. Summarize and discuss the relative configuration of the sixteen (16) African Game Parks. Provide specific examples to support your summarization and discussion.

3. Summarize and discuss the joint configuration of the 9 Herbivore Tribes and the 16 Game Parks. Provide specific examples demonstrating which herbivore tribes are most closely associated with which Game Parks.

4. Overall, do you feel that the CA ordination biplot provide a good summative model of the data? Justify your answer, citing specific examples.

NOTE: Remember that CA emphasizes relative, rather than absolute, abundances of the 9 Herbivore Tribes in the 16 Game Parks. Refer to the percentage abundance values (Table 1) to help in answering this question.

5. Superimpose the 4 groups of Parks (from the Ward3sum of squares cluster analysis, top of Page 15), and the 3 groups of tribes (from the Ward3sum of squares cluster analysis, bottom of Page 15) onto the CA ordination diagram (Figure 1). Do the group structures imposed by the cluster analyses reflect the relative positioning of tribes and parks in the CA ordination? Comment on how cluster analysis and ordination are complementary analyses for the modeling of data trends.

NOTE: Use symbols and/or colours, superimposed on Figure 1, to denote group affinities.

Part B - PCA And NMDS: Pacific Coast Forests, Washington

6. What are the major floristic trends summarized by the PCA axes 1 vs. 2 (Figure 2)? Which species (variables) are weighted most highly on the first two PCA axes?

7. What percentage of the total variance is accounted for by PCA axes 1 and 2? Summarize the relative importance of the first and second PCA axes in accounting for floristic variation.

8. Referring back to the raw data (Page 21), comment on the PCA configuration of the 48 plots; i.e. does the configuration reflect trends in the species? Provide specific examples and summarize major trends.

9. Compare the PCA (Figure 2) and NMDS (Figure$3) ordination configurations of the 48 plots. Do these two ordination methods produce similar two-dimensional configurations (summative models) of the 48 plots? Provide specific examples to support your answer.

Part C - Redundancy Analysis: Pacific Coast Forests, Washington

10. Interpret the results of the permutation test for floristic differences among the six watersheds (Page 35). Are floristic differences among the watersheds statistically significant (at P < 0.05)? If so, how many RDA ordination axes (dimensions) are significant?

11. What proportion of the total variance is explained by floristic differences among the 6 watersheds, i.e. the constraining variables? Summarize the relative importance of the first and second RDA axes in accounting for floristic differences among the watersheds.

12. Comment on and summarize the RDA configuration (Figure 4), with particular reference to the relationship of the 6 watersheds (WS1-WS6), the 48 plots, and the 20 species.

Use the RDA configuration (RDA axes 1 vs. 2, Figure 4), together with the raw data set, to answer the following questions:

13. Which two watersheds have the highest cover of the softwood trees western hemlock (HEM) and western red cedar (CED) and lowest cover of the hardwood trees big-leaf maple (MAP) and red alder (ALD)? Provide evidence from the raw data to support your answer.

14. Which watershed has the highest cover of the hardwoods (MAP, ALD) and low cover of the softwoods (HEM, CED)? Provide evidence from the raw data to support your answer.

15. Which watershed has the lowest cover of Douglas fir (FIR)? Provide evidence from the raw data to support your answer.

Attachment:- Analysis of Biological Communities Assignment File.rar