Compared to much of Antonioni's other "documentary" footage, these five grabs are nice and short: maybe less than a minute of footage each, and very sweet, especially if you're a naturophile.
Mandorli is exquisite footage of white blossoms in bloom. Vulcano is helicopter shots of a volcano. Stromboli is helicopter shots of some kind of a mountain covered with coal/ash or some such. The piece de resistance, though, which is actually really wonderful - is Carnevale. Antonioni cuts to the same helicopter shot, but this time filming a sea of people. He really thought people were insignificant compared to nature! The italians really know how to do a parade, and it looks beautiful on film. A treat.
The way Antonioni does these "documentaries" is he films natural scenes and screens them with no commentary - so be prepared for that.
You can catch it in the short film program that screens with the Antonioni retrospective that's touring the world: it was at Venice in 2000 and its just been at Sydney in 2004, at the annual film festivals of both. When it comes to a festival near you, i don't recommend it as worth your while. See the features instead, especially Red Desert, Zabriskie Point, La Notte, L'Eclisse, along with the famous ones L'Avventura and Blowup.