Here's one. I can't seem to raise the PDF version but you may be able to access it from here.
http://72.14.253.104/search?q=cache:vAqBqP2lSSoJ:www.sfu.ca/~qgrc/zazula_2003a.pdf+mosaic+vegetation+ancient+tundra&hl=en&gl=nz&ct=clnk&cd=8
Another one you might find interesting re. climate change. Couple of quotes from the post:
"It is true that in many areas during the LGM, the vegetation combined species that normally grow well apart from one another in separate vegetation/ecosystem zones. The most striking example is the steppe-tundra (Tallis 1990) which brought together species of modern-day steppe and tundra vegetation respectively. To a lesser extent, the same is true of much of early and mid Holocene vegetation of the world."
"In any case, it is sometimes difficult to decide whether these no-present-analogue vegetation types were similar enough to any presently widespread vegetation type to be mapped and treated as such. In the case of the steppe-tundra of the LGM, the difference from present vegetation is suggested here as being too great to fit into any of the standard present-day vegetation categories."
http://www.esd.ornl.gov/projects/qen/adams2.html Other sites came up for "mosaic vegetation ancient tundra" but I couln't access them. Not a member etc. If you already subscribe to some of these sites you would find more info.
