METHODS OF DATA ANALYSIS 



Data analysis initially resulted in the identification of the degree of 

 change in measured parameters at each study site. A numerical rating ranging 

 from to 10 was assigned to indicate an increase (ratings 10 through 6), no 

 change (rating of 5) or a decrease (ratings 4 through 0). These ratings 

 indicate the degree of change at the time of the site visit between the 

 pre-gravel removal conditions (i.e., extent of shrub thicket cover, or 

 number of passerines present) and the post-gravel removal conditions. Each 

 numerical unit increase (6 through 10) or decrease (4 throijgh 0) approxi- 

 mates an alteration similar to a 20 percent level of change in that param- 

 eter. 



Each site was analyzed to determine how measured parameters (vege- 

 tation, soils, birds, and mammals) interacted, and how they responded as a 

 whole to the Physical Site Characteristics (such as river size and config- 

 uration) and Gravel Removal Area Characteristics (such as type and location 

 of gravel removal). After individual site analysis, all sites were compared 

 to evaluate similarities and differences in the degrees of change in biolog- 

 ical parameters. 



Fauna directly respond to the presence (and type) or absence of vegeta- 

 tive development, consequently, the degree of change and the rate of re- 

 covery at the gravel removal sites received major emphasis in the vegetative 

 data analysis. Factors that influence vegetative recovery (e.g., soil con- 

 ditions and aufeis development), also were thoroughly reviewed. 



Selected biological data were subjected to a computerized hierarchical 

 clustering routine to identify similar responses in a measured biological 



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