Visual and sound environmental art is a foundation of contemporary landscape architecture. In the last half of the 20th century especially, ideas many artists globally critically engaged questions typical to landscape architecture (space, texture, materials, habitation, connection to the Earth) but interrogated these topics in an experiential and inquisitive manner. Two resources that warrant some review:
Vast written and visual resources related to visual environmental art (land art, ecological art, earthworks, etc.). Heaps of great artists with inspirational works.
Network of environmental sound artists/designers. Array of sound recordings available for listening right from the site.
marshall, I really like your blog. keep writing! mwah~