Hello Reza

You can use Fdiversity software.

Hello Reza,

Have a look at:

de Bello, F., Leps, J., Lavorel, S. & Moretti, M. 2007. Importance of species abundance for assessment of trait composition: an example based on pollinator communities. Community Ecology 8: 163–170.

Pillar, V.D., Blanco, C.C., Muller, S.C., Sosinski, E.E., Joner, F., & Duarte, L.D.S. 2013. Functional redundancy and stability in plant communities. Journal of Vegetation Science 24: 963–974.

Hope it helps!

Hello Reza,

I strongly recommend you reading this article:

Mouchet, M. A., S. Villéger, N. W. H. Mason, and D. Mouillot. 2010. Functional diversity measures: an overview of their redundancy and their ability to discriminate community assembly rules. Functional Ecology 24:867-876.

One way to calculate the functional redundancy is to apply the MFAD, but I  recommend seeing some "problems" with this metric in the article quoted above. MFAD = Modified Functional Attribute Diversity (Schmera, Eros & Podani 2009).

Schmera, D., Eros, T. & Podani, J. (2009) A measure for assessing functional diversityinecologicalcommunities.AquaticEcology,43,157–167.

In the R-program exist several packages that calculate the functional diversity in its different facets, such as, FD and SYNCSA packages.

Best regards

Dear all participants

Thank you very much for your useful answers.

Best regards

Reza

Dear Reza. I strongly recommend recent this vewpoint paper:

"The dark side of the “redundancy hypothesis” and ecosystem assessment"

http://www.sciencedirect.com/science/article/pii/S1476945X16300551

and a conceptual-analytical solution: 

"Traits Without Borders: Integrating Functional Diversity Across Scales"

http://www.cell.com/trends/ecology-evolution/abstract/S0169-5347(16)00045-8