I’ve been trying to come up with a metric for species (dis)similarity for fish in a series based on presence or absence data that gives a value of 1 or 0 for each lake. From my research, it seems like a Multi-site dissimilarity index using Jaccard index would work best, as single-site presence/absence for each lake doesn't need nestedness or special turnover caveats. Calculating a measure of beta-diversity in R through 'betapart' gives an overall value of 0.86. Now I want to come up with a value of (dis)similarity for each site, that I can then use to plug into an RDA as a continuous variable. Is there a method of calculating site-specific dissimilarity? The closest thing I can come up with is taking beta diversity across all sites =0.86, then calculating a measure of how many species are present in each lake divided by 0.86, kind of using a makeshift Jaccard index formula. For example site 1 would be =(1/7)/0.86; although I don't know if this violates any assumptions. Below is the data that I used.

Species1 Species2 Species3 Species4 Species5 Species6 Species7

Site 1 1 0 0 0 0 0 0

Site 2 1 1 0 0 0 0 1

Site 3 1 1 1 1 1 1 1

Site 4 1 0 0 0 0 0 0

Site 5 1 0 0 0 0 0 1

Site 6 1 0 0 0 0 0 0

Site 7 1 0 1 0 0 0 0

Site 8 1 0 0 0 0 0 0

Site 9 1 0 0 0 0 0 0

Any feedback would be greatly appreciated.