We propose to install a 1st propotipe of a net of instruments that will measure, in a automatic way, the light-pollution and aerosol content in the sky of the Doñana Biological Reserve. By a direct comparison with similar measurements are well known dark and clean locations we will establish the actual quality of the night-sky. A longterm follow-up will allow us to determine the level of degradation of these environmental parameters, indicating the most probably origin, and helping us to propose the most optimal solutions to limit the effect of this degradation.