Landi accepted a position as a draftsman for an expedition demarcating Portuguese territories in the North Region of Brazil under Dom João V. He left Bologna at the end of 1750 or beginning of 1751, taking a boat in Genoa bound for Lisbon.
The commission stayed in Belém for a year before moving up to the upper Rio Negro, the theater of future operations.
His manuscript on the natural history of the Amazon, Descrizione di varie piante, frutti, animali, passeri, pesci, biscie, rasine, e altre simili cose che si ritrovano in questa Cappitania del Gran Parà (ca.
1775), has been annotated by zoologists Nelson Papavero, Dantes Teixeira, and botanist Paulo Cavalcante and published by the Emilio Goeldi Museum of Pará.
On the contrary, his presence in Brazil - and in the more tropical Brazil that is the Amazon - meant the introduction of new technical and artistic forms and concepts to the region at that time, and the happy convergence of styles in vogue in Italy and Portugal, without forgetting the intimate correlation between architecture and the environment, a phenomenon that Landi had the sensitivity to perceive."