The Made of Light project by Speirs Major and Associates Lighting Architects http://www.madeoflight.com/mol/site_map.htm is a wonderful e-book that discusses the relationship between architecture and light in 12 simple themes.
1. Source – natural and artifical
2. Contrast – light and darkness
3. Surface – light and texture
4. Colour – spectral colour
5. Movement – where time meets space
6. Function – the ability to see
7. Form – visual shape of mass and volume
8. Space – the absence of mass
9. Boundary – to unify or separate
10. Scale – the comprehension of size
11. Image – creating identity and charater
12. Magic – phenomena which can inspire us
The photographs above pick up many of these themes in the use of light in the landscape.