Dear list,
As I know(according to other related papers), the inflation factor of environmental variables in CCA should be less than 20. But, when I conducted it(in CANOCO version 4.5),  the final result revealed the inflation factor of two key environmental variables are 25 and 26(>20). The two variables are percent of forest landuse and impervious surface, which I want to keep in the analysis.
My question is whether I could transform the two factors to decrease the inflation factor or not? Or there is any better choice for me? 
Maybe this is not an "R" issue. But I really couldn't find a better place to propose such a question. Thanks in advance for your time and suggestion.
Best, 
Shuoru



Liu Shouru
Department of Entomology
Nanjing Agricultural University
Nanjing, Jiangsu Province 210095
P. R. China

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