The thread is about using live sphagnum moss cover instead of mulch wich its dead matter.I didnt mix them with the soil.
Again, you're not talking about sphagnum moss. The moss in your photograph is not sphagnum moss. It's something from a different genus entirely. And yes, the moss of your kind as a 'mulch' is fine to use. In nurseries it often grows over the top layer of the soil naturally. That said, it's not going to be viable as a true mulch for anything more than situationally for the long term. You will burn it and kill it whenever you try to add topical fertilizers or nutrients. it will die off when you move the tree in to direct sunlight because it requires shade. The seedlings in your picture do not even require any mulch at all, in fact--and probably aren't even benefiting from the presence of the moss in any way. Perhaps this aids in water retention slightly more uniform soil moisture, but beyond that it's not doing anything at all. This is actually the way mosses contribute to the biocycle; they keep soil wetter for longer, which aids in decomposition of organic matter, which contributes to a more readily available nutrient (especially carbon) density available for plant uptake. They also aid in in situ fungi development which is beneficial to root health, but again, that's all got to do with moisture. Unless there's leaves and wood buried in your mix, this effect is not doing anything for the overall health of those seedlings. It isn't hurting them, either. It's just not doing anything at all.It's fine for tiny little seedings, but it's not a practical, nor intelligent, solution to anything beyond this. If it was, professionals would be doing it, and they aren't.