ACE metric for alpha diversity

good evening, I'm going to ask a question that already exists in the forum, but I can't quite understand. it's about alpha diversity and beta diversity. let's be practical, I have a set of samples with 5 experimental groups. When I perform the alpha diversity analysis (most of the metrics are not significant, only the ACE index comes out significant ... I have searched on this index and I cannot find what I am looking for, the explanation of what it does exactly and that as it translates into my samples). I also do not understand that if, for example, the Shannon index is significant (I understand that then the richness and abundance between groups is different) and the beta diversity then what is it for? what a mess ...

Welcome to the forum, @Edgar1991 ,

It sounds like you are looking for an explanation of the different diversity metrics. This topic gives a brief description and original reference for the various diversity metrics, so I recommend starting there and check out the literature (or even wikipedia) for more details on these metrics:

Good luck!