Rolf Stange is a polar guide who has written several guide books in multiple languages on Spitsbergen. He also holds a very informative website
https://www.spitsbergen-svalbard.com, where you can order these books.
In 2009, I was send with him on a trip to Antarctica (website in Dutch).|
Today, we discussed the effect of grazing on the vegetation. I send him a few pictures and he returned two nice pictures making the statement. He lifted a fish box lying on the tundra and the gras underneath was much more biomass. Of course warming might have helped too. But my exclosures show these effects too.
Do realize that in most cases, the arctic tundra is a grazed tundra and it would differ in biomass and species composition if grazing had not happened!