Luigi Russolo, Italy 30th April 1885 - 6th February 1947.
Luigi Russolo believed that we were becoming so used to the sounds of an industrial soundscape that future musicians would be able to start composing with these sounds. He considered that noises were just as important, if not more so, as the sounds of musical instruments.
What Russolo proposed is not so very different from how soundscape composers are working today and his work can be considered a progenitor to modern acoustic ecology.
Russolo, L. (2004). The Art of Noises: Futurist Manifesto. In C. Cox and D. Warner (Eds.). Audio Culture: Readings in Modern Music. (pp. 10-15). Continuum International Publishing Group Inc.
Photo: National Taiwan University Institute of Musicology. (2013). Russolophone. Retrieved from http://2013sound.blog.ntu.edu.tw/?s=Russolo&submit=
As it grows ever more complicated today, musical art seeks out combinations more dissonant, stranger, and harsher for the ear. Thus, it comes ever closer to the noise-sound.
Russolo, 2004, p. 11
The video below shows a performance of Russolo’s approach to noise music, using replicas of his Noise Intoners. The first few minutes contain an interview with Luciano Chessa who curated this performance, where he discusses some of the meaning behind the music.

Photo: Digicult. (2009). Performa. Retrieved from http://www.digicult.it/wp-content/uploads/2009/11/performa.jpg
Video: Digicult. (2012). Music for 16 Futurist Noise Intoners. [YouTube]. Retrieved from https://youtu.be/Lqej96ZVoo8
Russolo wrote about his ideas to compose with noise in a letter to Francesco Balilla Pratella in 1913, which contained his manifesto called The Art of Noises. The manifesto was focussed on the artistic aspect of environmental sound rather than any sort of ecological or scientific issues, and as such does not really play much more of a role within the story of acoustic ecology. Nevertheless, Russolo’s work was groundbreaking and modern approaches to music owe his realisation a lot, but there are others who advanced upon his initial ideas and further help unravel the history of acoustic ecology.