Hi there,

I have a general question which I cannot seem to find the answer for online.

Say you are calculating functional diversity metrics for an ecological community over time. In some years species richness = 4/5/6 and some years species richness = 0/1/2. My understanding is that depending on the metric, you can assign a value of 0 for communities in years where species richness = 1 or 2 and NA to those with species richness = 0. However, isn't it informative to know that a community is not functionally diverse in years where species richness = 0 because there are no species there? If we use NA for years where species richness = 0 then we are only producing trends based on years where species richness is at least >0. This may be misleading if we are trying to determine the stability and health of ecological communities over time.

I would be interested to know your thoughts.

Many thanks!