This podcast is based on the first chapter of a book by Tom Turner published in 1996: City as landscape.  The chapter's title was post-Postmodernism but  if the term Landscape Urbanism had had its present use in 1995 it would have been included. 
The ‘layering’ aspect of Landscape Urbanism derives from Ian McHarg and his use of reason was certainly affected by his beliefs. McHarg was anti-Christian, sympathetic to Buddhism and a great believer in the importance of conserving nature. Me too.
Conservation wasn’t an aspect of either Modernism or Postmodernism.  But it’s built-in to Landscape Urbanism, which we should therefore classify as post-Postmodern. If revising  this chapter, I’d change most occurrences of the word ‘religion’ to ‘beliefs’, for the reasons explained in my book on Asian Gardens: History, Beliefs and Design  (Routledge, 2011).