I want to study the impact of aquaculture on a hard rocky seafloor community which is naturally low in diversity.
4 replicate images (0.25 m2 each) were taken at fixed distances (0, 20, 40, 80, 120, 160 and 200 m) along 8 transects away from the aquaculture site.
The database has 15 different taxa, some of which are continuous (regular abundance data, from 0 to 16) and others are categorical:
0 = 0% 1 = 1-25% cover 2 = 25-50% cover 3 = 50-75% cover 4 = 75-100% cover
There’s also lots of zero in the database.
I want to know if the benthic community changes based on the distance away from the aquaculture site.
My 1st approach was to transform my species database to presence/absence. Results are interesting but presence/absence is a drastic transformation and I would like to know if other options are available.
My questions are:
1. When performing a single multivariate ANOVA (aka PERMANOVA) and dealing with a species database containing categorical and continuous data, is there other transformation possible than presence/absence?
2. Would a standardization be appropriate?