The microbiota is the population of microorganisms (bacteria, fungi, viruses and mites) inhabiting the skin / wound.
The microbiome is the wound ecosystem of which the microorganisms (the microbiota) form part alongside the products resulting from their interaction with the wound environment.
Microbiota is the newer and correct word for what was formerly referred to as microflora. Microflora indicates that the microorganisms in question would be of the Plant Kingdom, which, of course, is incorrect.