[en] After a brief recall of a definition of biodiversity, and of the threat created by soil artificialization, this article presents nuclear energy as a dense and space saving energy, and states that the maintenance of nuclear production basis almost does not require any new soil artificialization. The footprint of nuclear activities is commented: important contributions of the enrichment phase and of real estate, a better assessment for nuclear than for other energy production means. The article outlines the strength of regulation on water and a rigorous control system to which a power plant is submitted. The high number of different environmental controls performed every year is finally outlined