I think you can find usefull this work on multimodal analysis

http://sustainability.curtin.edu.au/local/docs/perth_snamuts_report.pdf

For connectivity measures I have used Fragstats

http://www.umass.edu/landeco/research/fragstats/fragstats.html

and the extensions Pach Analyst 5 for ArcGIS 10 (ESRI).

I recommend you "Measuring landscapes: A Planners Handbook"

Thanks to all who have given wonderful suggestions

The igraph package in R (http://cran.r-project.org/web/packages/igraph/index.html) is also very useful for computing connectivity indices.

Do you find the software which can measure the accessibility index? could you tell me?